84 Replies Latest reply on Aug 6, 2014 3:25 PM by ngojas2001

    Have a question about radio or wireless communication?  Ask me!

    Chris_Pinter

      This thread has been closed to new questions.

      However, we welcome you to Post Your Questionabout Communications in the element14 Community Wireless Communications Technology group. You'll find many fellow members and experts who have just the answer you're looking to find! 

       

      Thank You, Your Friends at element14 Community


      chrispinter.gif

       

      Christopher Pinter

      As the founder and President of Pinter Electronics Consultants Chris has been instrumental in developing the business from its inception in 2005 to its current status.  He has over 15 years of experience in radio and wireless communication hardware design and product development. Chris graduated from the Okanagan University with a diploma in Electronic Engineering Technology and the British Columbia Institute of Technology with a Bachelor of Technology in Electronics.

        • Re: Have a question about radio or wireless communication?  Ask me!
          Calvin

          Hi Chris

           

          I am trying to construct a server whereby it can be able to receive information and detect the location of a particular wireless signal.

           

          I have a product which is worn on the hand of a person. It is suppose to be able to detect the pulse rate of the particular person and if this pulse rate exceed the "critical pulse rate" set in the program, it will transmit a signal through wireless to the server. The server would then tell the location at which this signal is send from and show the information of the person.

           

          The problem is that I do not know how this server could be set up. Could you help?

           

          Thanks

           

          Calvin

            • Re: Have a question about radio or wireless communication?  Ask me!
              Chris_Pinter

              Hello,

               

              This should not be to hard to do. However there are a lot of different issues you will need to address.  More then what I can comment on this forum.   I will need to get more information from you.

               

              For the sack of simplicity here are some of the issues.

               

              1. Location of the access point

              2. Detection of the access point IP address and mapping it to a location.

              3. Accuracy of the system.  How close does the location system need to represent where the person is.

              4. Cost of the system

              5. Time to market - Do you have time for research and time to develop the system?

              6. How do you monitor the system.

               

              You will need to provide me some more details about the project.  Please look at my contact info on www.pinterec.ca

               

              Chris

                • Re: Have a question about radio or wireless communication?  Ask me!
                  Calvin

                  Hi

                   

                  My aim Is actually to build the whole system in an old folks home. This server should be in a room. The old folks will be roaming around in the homes, wearing this watch which will transmit out signel when "critical" limit is achieved.

                   

                  The system need not show the exact location but at least let the person who is monitoring server, which level and room the signal is transmitted from.

                   

                  The cost I hope it could be as cheap as possible. I have the time, about couple of months.

                   

                  I do not know what point 2 mean.

                   

                  Thanks

                  Calvin

                   

                    • Re: Have a question about radio or wireless communication?  Ask me!
                      Chris_Pinter

                      What I am refer to is that you need to be able to determine which access point is receiving the signal.  If you only have a couple of months to do this task it is likely not a finished product.  I would suggest considering using the area the access point as a zone.  Ofcourse most access points can cover 3 different levels.

                       

                      I think you biggest problem right now will be a proof of concept and a project plan.   I see a number of wholes in your logic that will need to be looked at .

                       

                      1. Determine the range of an access point.

                      2. Create a prototype transmitter and test your system to determine the region of the alarm.

                       

                      With this you might be able to devleop a low grade non medical system as a demo.

                       

                      good luck,

                       

                      Chris Pinter

                        • Re: Have a question about radio or wireless communication?  Ask me!
                          jvdberg@ieee.org

                          On the following website you will find a description of a direction finding system. http://www.signal.uu.se/Publications/pdf/c0110.pdf The pattern of the antenna can be changed by steering the parasitic elements. This way the antenna pattern can be rotated electronically. The rotation speed could be between 12 Hz and 2 kHz. Don’t use a frequency that has any relationship with the mains frequency and don’t use a frequency outside the bandwidth of the receiver. The point of maximum signal can be compared with the actual position of the antenna pattern. This way the direction can be determined.  With two such systems at different locations you can find the position of the transmitter. The antennas could be located at the balconies on both sides of the building.

                      • Re: Have a question about radio or wireless communication?  Ask me!
                        ngojas2001

                        Dear Chris,

                         

                        I am a pipeline engineer, trying to build what I call "Pipe Radiowave Transmitter and Receivers".  

                        My test pipeline is 2 inch diameter and 300 m long. About 100 kHz Radiowave signal  from a commercially available RF generator (0.2kHz -2MHz)  is amplified  and aerialed through the pipeline. Receivers are placed at other side. The Transmitter and reciever aerials are install in the pipeline.

                         

                        Please see if the Block diagram below make sense to you? What comes out as output of the RF is current that are varying at radio frequency. Is this correct?




                         

                         

                         

                         

                        1. Transmitting antenna (about 100kHz. Must be attached to the RF amplifier)
                        2. RF signal amplifiers (about 100 watt) compatible with 5
                        3. Receiving antenna (broad range of frequencies) -compatible with 4
                        4. RF signal analyser (for the received signal)
                        5. RF generator (0.2 kHz -2MHz): Spec found: Manufacturer: GW INSTEK, Farnell Order Code: 4911684, Manufacturer Part No: GFG-8015G

                          

                         

                        This thread has been closed to new questions.

                        However, we welcome you to Post Your Question about Communications in the element14 Community Wireless Communications Technology group. You'll find many fellow members and experts who have just the answer you're looking to find! 

                         

                        Thank You, Your Friends at element14 Community

                      • Re: Have a question about radio or wireless communication?  Ask me!
                        heguoshen
                        hello.i write this note just want to say it is my first time to come to the great web site .i am from china and hope to make friends and exchange information
                      • Re: Have a question about radio or wireless communication?  Ask me!
                        Calvin

                        Hi Chris

                         

                        I have a digital data send from a particular device to the router(server) and I am suppose to extract the received data from the router. The router's job is just to receive the data. Is it writing a C++ program enough to extract and display the data on the computer.

                        How am I suppose to get on doing this if writing a C++ program is not the right way?

                         

                        Thank You

                        • Re: Have a question about radio or wireless communication?  Ask me!
                          migcracing

                          Hi Sir,

                           

                          I would like to design a project that functions depending on the signal strength of a RF signal. I read about received signal strength indicator, and somehow I think this is useful info. The concept of the project is to vary the output (e.g. a transducer) depending on the signal strength of an oncoming transmitter. What IC can i use? Thanks

                          • Re: Have a question about radio or wireless communication?  Ask me!
                            angeliesambayan27

                            Good Day Sir,

                             

                            We have a project that deals about locator. Our project must be a two way locator with an alarm. This alarm serves as an indicator that the one or both locator are out of range.

                            Sir what do you think we can use in our project

                             


                            Thank You,

                            Angelie

                            • Re: Have a question about radio or wireless communication?  Ask me!
                              eozores

                              Where I can buy a radio module which can integrate AIS in an ARM board and programmed with android?
                              http://es.wikipedia.org/wiki/Automatic_Identification_System

                               

                              ¿donde puedo comprar un módulo de radio para AIS que pueda integrar en una placa ARM y programar con android?

                              http://es.wikipedia.org/wiki/Automatic_Identification_System

                              • Re: Have a question about radio or wireless communication?  Ask me!
                                amalngg

                                hi i want to know  how i connect two or more office located at different places with radio or wireless communication.

                                  • Re: Have a question about radio or wireless communication?  Ask me!
                                    Chris_Pinter

                                    Hello Amalngg,

                                     

                                    Wifi was specifically designed for this application.   You want to look at 802.11A devices between buildings.  This protocal operates at 5.8GHz and is very line of sight...so you will not get a lot of interference as long as you use a directional antenna.

                                     

                                    For access to the wireless network within your building you want to use 802.11G or N devices to get the maximum bandwidth and user access.

                                     

                                    I hope this helps.

                                     

                                    Chris Pinter

                                      • Re: Have a question about radio or wireless communication?  Ask me!
                                        varunnigam19

                                        Sir,

                                             I have an issue deciding the value of speed while calculating the wavelength of a signal. The formula I am using is lambda = c/f where 'f' is the frequency and 'c' is the speed. The issue is, while calculating the wavelength of a signal with frequency, say, 10KHz, what should be the value of speed that I should consider? So far I have read in many books and also on the internet that the speed I should consider is the speed of light which I find as wierd because the speed of signals in the frequency range 20Hz to 20KHz is about 340 m/s in air since these are sound waves. So considering the speed of light for finding the wavelength of a much slower signal is something I dont understand.

                                          • Re: Have a question about radio or wireless communication?  Ask me!
                                            cookiemonster

                                            It depends on your detector.

                                             

                                            10KHz is just about the lowest frequency anyone ever calls "radio frequency." (Yes, some Navys use far lower frequencies, even in the single digits, for underwater, around the world, submarine communications, but that is rather, um, "special."

                                             

                                            But 10KHz is also within the range of human hearing. That begs the question...

                                             

                                            What method are you using to create and detect these frequencies? If you create it with an audio transducer ("a speaker" (a fairly small one)), then you are creating a mechanical wave ("a sound wave" in this case) which will travel at roughly 340 m/s in air (dependent on temperature, etc.) and you will detect it with something like a microphone. On the other hand, if you are creating your wave with an antenna then you will be creating a electromagnetic wave which will travel at 3x10^8 m/s and you will receive it with another antenna (another very long one).

                                             

                                            The general equation relating speed of a wave and wavelength is lambda = v / f. This is altered slightly into the form you provided, lambda = c / f for the special case of electromagnetic radiation (radio waves, microwaves, light, x-rays, gamma rays). In this case c (speed of light = 3x10^8 m/s) replaces the more general "v." But when dealing with mechanical waves, for example, sound, you set v equal to the speed of sound in the medium being analyzed. Note that speed of sound in air and water are much different.

                                            • Re: Have a question about radio or wireless communication?  Ask me!
                                              Problemchild

                                              Your formula is still valid the "c" in this instance should be subsituted for the speed of the wave in the medium you are working with.

                                               

                                              So for say Radio in outer space then the 'c' would indeed be the clasical Speed of light in a vacuum  however if you are talking about the speed of a sound wave from say a train at sea level you need to obtain the speed of the wave in that circumstance which is indeed around the 340M/s

                                            • Re: Have a question about radio or wireless communication?  Ask me!
                                              aml
                                              help,i 'll use face recognition in my project and i intend to use web cam to take pictures of people who 'll enter a building .these pictures are videos and i want to connect the cam with computer wireless by access point (WiFi) so,i need your help.is it possible? i exactly want to khnow how to connect web cam to computer but wireless .is there any interface 'll be between them? i need your help.it's an urgent need. Thanks
                                          • Re: Have a question about radio or wireless communication?  Ask me!
                                            pauloliver

                                            Hi Chris,

                                             

                                            I have a customer who wants me to design a ticketing product. The object is that the unit price must be low, but the quantities should be high. The size must be very small. The product will include a display, microcontroller and RF link. My customer anticipated using RFID for the RF link but as I understand it, the tags are stand-alone and do not have a wired read or write interface to a microcontroller. What I need is NFC (near field communications) but I cannot find any off-the-shelf modules that I can use. Looking around at other technologies, there are RF interfaces at 433, 868 or 915MHz (Alpha modules) and I have found small antenna at these frequencies.

                                             

                                            My brief at the moment is to prove the concept and provide a demonstration unit. Designing the completed product will only follow if a customer can be found justifying continuing development of the product.

                                             

                                            Can you suggest any other solutions that I should be looking at?

                                             

                                            Kind regards,

                                            Paul

                                            • Re: Have a question about radio or wireless communication?  Ask me!
                                              bpost

                                              Hi Chris,

                                              I want to start working on a project that I am not sure where to start (because I have little knowledge of electronics). Here is a basic example of what I want to do. Lets say I have some lights including their own power source and farther away I have a control board with some buttons on it including its own power source of course. If I wanted to wirelessly turn on any light individually or simultaneously how would I do so?

                                              Question is simply: What can I use as a transmitter and receiver (maybe an IC of some kind)?

                                              I can wire and solder fine so no problems there but I just need advice as to what components I would need to use

                                              thanks,

                                              bp

                                              • Re: Have a question about radio or wireless communication?  Ask me!
                                                f.anwar

                                                i like to use NFC with suitable microcontroller on my project so i don't have to use LCD to display current/voltage/temp instead this varibales can be display using any existing NFC cell phone. Can you suggest any NFC devices thats i can buy from element14. Thanks

                                                • Re: Have a question about radio or wireless communication?  Ask me!
                                                  carl007

                                                  Chris:

                                                  I'm looking for an off-the-shelf low cost < $75 solution for wireless remote control relays. Basically, I want to remotely control a six (6) zone  24 VAC, (0.3 A inrush) automatic sprinkler valve..

                                                  This is similar to what is available to remotely turn on an outdoor holiday display e.g. 75 range. But instead of switching 120VAC it would provide a six (6) SPST dry contacts.

                                                  • Re: Have a question about radio or wireless communication?  Ask me!
                                                    midhunharikumar

                                                    Hi

                                                     

                                                    I'm trying to transmit voice data over a 433mhz fsk module . it has 4 data lines and i am able to send data eazily but not able to

                                                    achieve the tx rate nessesary to transmit the data losslessly. Is there any encoding scheme that i can apply to achieve better fidelity ....

                                                    • Re: Have a question about radio or wireless communication?  Ask me!
                                                      ajaydange

                                                      I want to build a system which monitors water flow from pipeline and   detects the clogging if any

                                                      so i need to embedded a sensor, a microcontroller and a RF module  together..please help  me out to find  a suitable rf module

                                                      regards

                                                      • Re: Have a question about radio or wireless communication?  Ask me!
                                                        mukund.agarwal07

                                                        Hello Chris,

                                                        i have a small question that is it possible to convert radio and micro waves coming to our mobile during a call to be converted in to electricity,i am working on that please suggest me appropriate way

                                                        • Re: Have a question about radio or wireless communication?  Ask me!
                                                          kamil

                                                          I want to know that is there any way to impelement the concept of cognitive radio practically, if yes then  how much will it cost ?

                                                          • Re: Have a question about radio or wireless communication?  Ask me!
                                                            tolu collins

                                                            Hello Chris

                                                             

                                                            Is is possible to create a wireless network in an embedded system based on say an arduino shield or microchips TCP/IP stack, and have a mobile or android app connect to that network in a automation system?

                                                            • Re: Have a question about radio or wireless communication?  Ask me!
                                                              wjmicrodyne

                                                              I have made a wireless application using microchip miwi. I want to link to wifi to get the data to the internet. Have you seen any examples of this linkage? Microchip has little or no documentation on this. Is there a better approach? 

                                                              • Re: Have a question about radio or wireless communication?  Ask me!
                                                                smertrios

                                                                Hi, I'm working on a location-based system which trilaterates wifi signals.  Currently, mobile assets are tracked using off-the-shelf battery-powered wifi modules. 

                                                                 

                                                                No real wifi communication is needed between the tag/AP other than measuring the tag RSS on the AP side. 

                                                                 

                                                                I'm looking for information on what it'd take to build a stripped-down, bare mimimun, "fake" wifi node whose only job would be to transmit a hard-coded probe frame? 

                                                                 

                                                                what would be the minimum hardware to transmit that hard-coded frame?  Any cost/pro/con comparison with off-the-shelf full-wifi solution?

                                                                 

                                                                I'd appreciate any info/pointer.

                                                                 

                                                                Thank you

                                                                • Re: Have a question about radio or wireless communication?  Ask me!
                                                                  dus_SL

                                                                  I need to send 10-bit data from the Analog to digital converter(ADC) from a dsPIC at 2Mbps through UART interface, to a bluetooth module. Then the bluetooth module should read this data through its UART

                                                                  interface and transmit this data via bluetooth which will be finally received by an Android phone. An application in the phone will take this data and plot a waveform on the screen.

                                                                  So basically the phone will recieve data at 2 Mbps via bluetooth. Is this practically possible ?

                                                                  Most bluetooth modules say they can transfer data only around 300 kbps using RFCOMM protocol. Is there any reason for this ? It says to go upto 2Mbps it is needed to use the HCI protocol whch needs to be implementedon the host processor. So then can the Android phone read data sent in HCI protocol. Is there any support available. Currently all transfers done in Android which I found are in RFCOMM. Is there any way either using RFCOMM or any other means for Android phone to aquire atleast 1.5 Mbps data via bluetooth ?


                                                                  What bluetooth module would you suggest is best for this application ?


                                                                  Thank you,

                                                                  Best Regards.

                                                                  • Re: Have a question about radio or wireless communication?  Ask me!
                                                                    danidub

                                                                    Hello I'm planning a HAB and for that I choose the RADIOMETRIX  NTX2-434.650-10NTX2-434.650-10 TRANSMITTER 434.65MHZ 10MW

                                                                    the balloon wil be 30 km from earth and sending messages RTTY to my ICOM-IC R20 in ssb mode 70cm. but I dont know what antenna to use for the balloon, neither for the ICOM IC-R20.


                                                                    Can you please help me?

                                                                    Thanks, Daniel

                                                                    • Re: Have a question about radio or wireless communication?  Ask me!
                                                                      soulsmile

                                                                      Hi Chris I did post this as a general question but with your experince I would greatly appreciate some advice if you can spare the time!

                                                                       

                                                                      Im about to embark on electronics/comms/telecomms training. After that I want to specialise into something?

                                                                       

                                                                      Im looking at Scada/control systems, wireless comms and RF.

                                                                       

                                                                      While I have a background in programming and some physics the technical aspects/terminology are daunting as all these fields offer a myriad of avenues. Im good at understanding requirements, working with people up to board level and making things happen/solving problems

                                                                       

                                                                      My question is this:

                                                                       

                                                                      1. Im looking for the most mobile skill( I love travelling and wayout places ) and obviously well paid

                                                                       

                                                                      2. Where is the convergence going in these fields, so I can position myself correctly?

                                                                       

                                                                      3. It seems to me that Scada guys need a lot more training/diploma/degree and experience versus the RF/radio technician guys? Why do radio techs earn so much? How do you become a radio tech?

                                                                       

                                                                      4. I have family in Australia, my brother is an engineer there, and there are diploma courses that cover the basics of these technologies and have some elective choices. Is it possible to do more specialised training straight off(eg Motorola) if I can teach myself the physics etc?

                                                                       

                                                                      Im in South Africa and there is no specialised training here except for people who are already in the industry, so im looking abroad for training. Im in my 30's so Im not looking to go do a 3 year degree in Electronics, Id rather work and learn after studying for say a year, is this realistic or possible?

                                                                       

                                                                      Any advice, help, referals to other forums are very much appreciated!!

                                                                       

                                                                      Jano

                                                                      • Re: Have a question about radio or wireless communication?  Ask me!
                                                                        7589089188

                                                                        hello sir , i am making a project of transmitter.whose circuit diagram is shown below.i think this circuit diagram is right for me so i choose it to build my project.but there is one problem comes across me .i've found that i have bc547,bc548,bc337 type transistors only but the recommended transistor in this circuit diagram is bc338 which is not available in any shop in my town..so what can i do ????? can i am allowed to use transistors bc547,bc548 or bc337 in this circuit.actually i have taken this image from a video so the suggestion of using bc338 is given in the video..not given here in the image.the +9v dc input is given in the junction of coil,0.01 micro farad capacitor and 27 ohm resistor. -ve terminal of the battery is connected to the ground one terminal of audio input is given to the -ve terminal of 1 microfarad capacitor and second terminal to ground .....please suggest me solution as soon as possible ..i have to complete my project till next morning.....please also tell me the description of the full circuit step by step....thankyou very much sir               here is the image of transmitter made in the video..C.PNGCapt.PNG

                                                                        • Re: Have a question about radio or wireless communication?  Ask me!
                                                                          nonniebay85

                                                                          Hello,

                                                                           

                                                                               I would like to wirelessly sync my Altera FPGA DE1 board (Cyclone II) with another circuit as part of a project. Please help with whether or not it's possible, then what parts I would need for the build. I will only need to sync 1 byte (8 bits) at a time. Should I use a Wi-Fi card, infrared LED's, or bluetooth. I would like some help with the sync part only. Thanks for your help.

                                                                           

                                                                           

                                                                                        Robert Newstrand

                                                                          • Re: Have a question about radio or wireless communication?  Ask me!
                                                                            beacon

                                                                            Hi Chris -

                                                                            I am a not an engineer but I have a product idea which I would like to build that involves the idea of a wireless beacon. I am not sure if there are engineers (for hire) or companies that can create a product based on an idea you have to build it? Would appreciate any recommendations.

                                                                             

                                                                            Meanwhile, the idea I have is for a small (light/pager) size wireless beacon that must be run on a battery and is able to connect to a network (ie. phone or pager) independently upon power on.

                                                                             

                                                                            All help will be greatly appreciated.

                                                                             

                                                                            Thanks.

                                                                            • Re: Have a question about radio or wireless communication?  Ask me!
                                                                              astratvsports

                                                                              Chris Hi,

                                                                               

                                                                              I was wondering have you any experience of IPTV and the use of Roku receivers?

                                                                              Martin

                                                                              • Re: Have a question about radio or wireless communication?  Ask me!
                                                                                WVPhysicist

                                                                                New question:      Here is something I cannot figure out:
                                                                                I am an electronics engineer. I can design and build circuits if they are not too difficult. I can build audio stages and, I assume, we are all familiar with the design philosophy of the superheterodyne receiver.
                                                                                If on a bench, I throw together several audio gain stages (each has a gain of 10), somewhere around three or four I start hearing noise. This is amplifier noise, likely thermal and it means at gain of 1000, I have hit the noise floor. At this point adding more gain stages is futile because it only makes the noise louder.
                                                                                This is the point in radios where the detector is found. From the detector going forward the frequency band being amplified is changed from AF to IF or RF, an increase of about one thousand in frequency. There are usually two or three gain stages of IF. For some reason this does not increase the noise as the previous experience suggests. Instead the noise floor falls away and finally, as one moves along to the front end, receiver sensitivities around a microvolt are obtainable. This means the noise floor has dropped by a factor of a thousand.
                                                                                I can not understand how this can happen. According to thermodynamics we are on the low side of a black body curve which is flat up to infrared frequencies. So in any interval of say 15KHz bandwidth we should see the same noise power wheather it is in the audio range or the RF range. If this was the case radio would not be possible. So clearly something strange is happening and this has been well understood for more than 50 years.
                                                                                What is the explanation?

                                                                                • Re: Have a question about radio or wireless communication?  Ask me!
                                                                                  ankitsamal

                                                                                  Sir,

                                                                                   

                                                                                  I am using a SIM 300 module . Could u please help me with capturing the tower information.

                                                                                  • Re: Have a question about radio or wireless communication?  Ask me!
                                                                                    anakin59490

                                                                                    Hello Chris !

                                                                                     

                                                                                    I look for RFID tags which can be detected by a RFID over 1 meter distance. It's for a wine cellar management. For example, i wish (if it's possible) to take out a bottle without approach it towards the reader....

                                                                                     

                                                                                    I would like use Raspberry PI connected to RFID system with tags which have a long range (between 1 and 2 meter).

                                                                                     

                                                                                    Is it possible ? Can you help me for equipmenet choice ?

                                                                                     

                                                                                    Thank you

                                                                                    • Re: Have a question about radio or wireless communication?  Ask me!
                                                                                      allan1942

                                                                                      Hi Chris

                                                                                      I've just unpacked my new Raspberry computer and quickly tested it using my TV.

                                                                                      It seems just like the day when I plugged in my BBC computer many years ago. Sigh...

                                                                                      Then my wife handed me a slip of paper (the only documentation supplied with the bits & pieces)

                                                                                      It had escaped my notice. I read it and it carried compliance information.

                                                                                      I must admit that I've never read this sort of thing before, but squinting hard to read the small print, I see that the Raspberry  computer is not designed to be used in a residential area, only in a commercial environment.

                                                                                      For example, one of the statements declares that at my own expense I have to stop the thing from interfering with radios.

                                                                                       

                                                                                      In fact, I believe the slip of paper should be headed "Non-compliance Information" rather than "Compliance Information".

                                                                                      If it's intended for use in a home environment then it is NOT compliant with the appropriate EMC requirements of the various countries in which it is sold.

                                                                                      I wonder how many users have read and understood just what is said on the (back of the) slip of paper produced by Farnell?

                                                                                      What do you think Chris?

                                                                                      Is it just another source of problems for radio listeners?

                                                                                      regards

                                                                                      Allan

                                                                                      • Re: Have a question about radio or wireless communication?  Ask me!
                                                                                        aml
                                                                                        Hi,i 'll use face recognition in my project and i intend to use web cam to take pictures of people who 'll enter a building .these pictures are videos and i want to connect the cam with computer wireless by access point (WiFi) so,i need your help.is it possible? i exactly want to khnow how to connect web cam to computer but wireless .is there any interface 'll be between them? i need your help.it's an urgent need. Thanks
                                                                                        • Re: Have a question about radio or wireless communication?  Ask me!
                                                                                          Stevebissell

                                                                                          Hi

                                                                                           

                                                                                          I have a solar PV array which is about 80 metres from the house.

                                                                                          Communication with the inverters is by Bluetooth.

                                                                                          Using a class 1 USB dongle I can just communicate but the dongle is out of the window in a plastic  bag!

                                                                                          This is not a suitable long term arrangement!

                                                                                           

                                                                                          Looking at lm540 and lm 540 in Farnell  catalogue which offer high gain aerial options. I can mount the unit out of doors inside a suitable plastic box. With a short 3m USB extension cable

                                                                                           

                                                                                          Inverters are German manufacture SMA technology  

                                                                                           

                                                                                          Have been experimenting with Bluetooth repeater but no succsess

                                                                                           

                                                                                          Any comments on On. Use of 540 / 541. And differences between units. I can't see immediate differences from Ada sheet.

                                                                                           

                                                                                           

                                                                                          Host machine running 64 bit windows 7

                                                                                           

                                                                                           

                                                                                          Any general or specific comments gratefully received

                                                                                           

                                                                                           

                                                                                          Steve Bissell

                                                                                          • Re: Have a question about radio or wireless communication?  Ask me!
                                                                                            marekKnows.com

                                                                                            Hi Chris,

                                                                                            I'm building a home security system and I need a way to wirelessly transmit multiple sensor states from my doors, windows, lights, to the base unit.  How would I do this?  I would like to place 1 wireless transmitter at each of the locations that are being monitored, and then I need one receiver that can get all the n wireless signals and be able to differentiate which signal is coming from which sensor location.  Can you recommend some devices that will be able to do this?

                                                                                             

                                                                                            thanks,

                                                                                            Marek

                                                                                            • Re: Have a question about radio or wireless communication?  Ask me!
                                                                                              chrsimmo

                                                                                              When you're designing a bandpass filter (@ the antenna) for a microwave front-end receiver, what are the typical bandwidths that an engineer should design for?  As an example, I'm designing a receiver for the 2.417 - 2.450 GHz band, what start/stop frequencies would you design for?  I've found that the Cheby & Buttersworth filters using components and stubs are very difficult to physically design for such a narrow passband.  However with dielectric resonantor filters, I can achieve extremely small passbands.  Should I use such a small passband or are there other concerns that I should be cautious of?

                                                                                              • Re: Have a question about radio or wireless communication?  Ask me!
                                                                                                danilogurovich

                                                                                                Chris:

                                                                                                 

                                                                                                I'm looking for a short-range, wireless pressure sensitive pad and a fob with an alarm -- to connect both.

                                                                                                 

                                                                                                I also think I might need a raspberry pie instance to connect both, but if not it would be "cleaner".  Your thoughts apprecd.

                                                                                                • Re: Have a question about radio or wireless communication?  Ask me!
                                                                                                  stoneszhan

                                                                                                  Hi Chris,

                                                                                                  I wanna to consult you about the future of WIFI and Blutooth.Do you think the wifi will kill the bluetooth in the future?

                                                                                                   

                                                                                                  The friend in the field all prefer wifi to bluetooth.So i want to consult you.

                                                                                                   

                                                                                                  B.R.

                                                                                                   

                                                                                                  Ray

                                                                                                    • Re: Have a question about radio or wireless communication?  Ask me!
                                                                                                      Problemchild

                                                                                                      Devices have become smarter and demands on them have become greater. During this time WIFI implementations have become smaller more power efficient, cheaper and easier to implement some only require a simple serial link to drive them and include an entire TCP stack. Personally I think BT has had it's day in the smaller solution space where it wins out you may well be better implementing ZigBEE or any one of the "industrial control" solutions ?!

                                                                                                    • Re: Have a question about radio or wireless communication?  Ask me!
                                                                                                      salvadorutvt

                                                                                                      Hi Sir.

                                                                                                       

                                                                                                      I found a transceptor " nRF2401A " in other shop, and I would like to know if there is a similar product in Newark.

                                                                                                       

                                                                                                      My project is to send the signal of a sensor, but wiressly, this sensor is like a turbine and generates pulses with a magnet, I want to send theses pulses to the counter to calculate the water flow rate.

                                                                                                       

                                                                                                      I hope your help and recommendation.

                                                                                                       

                                                                                                      Salvador.

                                                                                                      • Re: Have a question about radio or wireless communication?  Ask me!
                                                                                                        shahudullah

                                                                                                        i want to make vehicle tracking system using gps module and gsm modem with the help of atmega16 microcontroller.plz help me.

                                                                                                        • Re: Have a question about radio or wireless communication?  Ask me!
                                                                                                          steengroentved

                                                                                                          Hello Chris.

                                                                                                           

                                                                                                          I need a very thin and flexible piece of ferrite to mount on the backside of an antenna for an NFC application. This seems perfect http://www.hitachi-metals.co.jp/prod/prod01/pdf/nfc_sheet.pdf

                                                                                                           

                                                                                                          But I can not find a distributor (and they don't answer to my email requests). Do you know if Farnell has something similar? (I have a little hard time on defining the right name for it, it might be why I don't find much anywhere).

                                                                                                          • Re: Have a question about radio or wireless communication?  Ask me!
                                                                                                            jorgerojas

                                                                                                            Hello Chris,

                                                                                                             

                                                                                                            I wanted to adapt an xbox 360 controller to connect wirelessly to my PC. I know there is already a microsoft product that does this, but it has a long cord, the device is relatively big compared to other wireless devices (a wireless mouse, for example), and it takes multiple controllers. I was thinking of making it as small as possible and make it pair a single controller. It is not necessarily the best application; however, I wanted to experiment with wireless technology. In other words, I wanted to do the project for the fun of it. Which wireless technology do you advise me to use. If there is a better way of doing this, then how?

                                                                                                             

                                                                                                            Thanks,

                                                                                                             

                                                                                                            Jorge Rojas

                                                                                                            • Re: Have a question about radio or wireless communication?  Ask me!
                                                                                                              brandon831

                                                                                                              Hi Chris,

                                                                                                               

                                                                                                              Want to create a wireless- remote control switch for a 115v winch motor that will function over 500 ft, obstructed line-of-sight. The motor is currently controlled by a DPDT momentary switch to engage forward and reverse. A 800 ft, 4-wires cable is currently used to connect power to the motor and switch to control the motor. I want to create a wireless switch control (Tx/Rx) units to untether the winch motor from the truck. A portable generator will be used to provide power directly to the winch and the wireless receiver. I want to use once channel for forward and separate channel for reverse. Reverse is accomplished by a relay within the winch motor.   I'm thinking of something in the 27Mhz  or 433Mhz band, around 1W to achieve this distance.

                                                                                                               

                                                                                                              I want to try and build this as a DIY project to learn about wireless controls.

                                                                                                               

                                                                                                              It seems simple in the idea, but struggling with where to start... Tx/Rx components needed, relays, etc.

                                                                                                              I have schematics for the motor wiring and the switch control box. Just want to replace the wire connecting them with a wireless connection.

                                                                                                              I can send them to you if that would help.

                                                                                                               

                                                                                                              Can you direct me some companies that can provide the components needed to build such a beast?

                                                                                                              • Re: Have a question about radio or wireless communication?  Ask me!
                                                                                                                pratap

                                                                                                                hi,

                                                                                                                     I need your help regarding selection of a proper RF diode(smallest available as i hv to incorporate it in a ring) to light up 1  SMD 3525 leds.

                                                                                                                 

                                                                                                                Appreciate your time, thanks in advance

                                                                                                                Pratap Singh

                                                                                                                pratap12330@gmail.com

                                                                                                                • Re: Have a question about radio or wireless communication?  Ask me!
                                                                                                                  prudhviraj

                                                                                                                  HIII SIR              

                                                                                                                   

                                                                                                                  why we cannot transmitt the electicity wireless ....??????????

                                                                                                                  • Re: Have a question about radio or wireless communication?  Ask me!
                                                                                                                    fredexx

                                                                                                                    I have built a DIY variometer for RC sailplanes which uses arduino and inexpensive 433 MHZ transmitter and receiver.

                                                                                                                    The suggested TX is RF Solutions AM RT14, which is not available at element 14 or anywhere in USA. I have used the AM RT4

                                                                                                                    with moderate success but really need the more powerful RT14. Can you suggest an available substitute.

                                                                                                                    Thanks

                                                                                                                    • Re: Have a question about radio or wireless communication?  Ask me!
                                                                                                                      nikhil555

                                                                                                                      Dear Chris,

                                                                                                                       

                                                                                                                      I am an electronics student with a project in mind and was wondering if you share some of your expertise on this.

                                                                                                                       

                                                                                                                      The project consists of a pressing a button ( switch) and sending that signal (of the button being pressed) to a website and a phone app. The system consists of many buttons , so that when one is pressed the website receives a signal as to that button has been pressed.

                                                                                                                       

                                                                                                                      My main problem is: How do I send that signal wirelessly over the air? Im thinking wifi, am i right? if so what hardward would I need.

                                                                                                                       

                                                                                                                      Thank you Chris

                                                                                                                       

                                                                                                                       

                                                                                                                      Kind Regards,

                                                                                                                      Nikhil

                                                                                                                        • Re: Have a question about radio or wireless communication?  Ask me!
                                                                                                                          Chris_Pinter

                                                                                                                          Hello Nikhil,

                                                                                                                           

                                                                                                                          Well....you can do it many ways... it depends really on what you want.  Most engineering projects start with a requirements document then a design concept.  I understand this is a university project so my advice would be to focus your study on one particular issue and use modules everywhere else.

                                                                                                                           

                                                                                                                          What I mean to say is.....  your project must demonstrate your new skills in one area of study.  I imagine this is not intended to be a wireless projects.  So.. get the simplest wireless solution you can find so you are not spending your time "developing" a minor part of your project.  Wireless technology can be complicated to eliminate the development risk as much as you can.

                                                                                                                           

                                                                                                                          WiFi will not be the easiest.  You will want to go with a bluetooth or 2.4GHz module.  use the evaluation kits and wire it up as a demo.

                                                                                                                           

                                                                                                                          Hope this helps,


                                                                                                                          Chris Pinter

                                                                                                                          www.pinterec.ca

                                                                                                                        • Re: Have a question about radio or wireless communication?  Ask me!
                                                                                                                          ak_bongo

                                                                                                                          Hello,

                                                                                                                          I have a question about wirelessly connecting two microcontrollers. I would like to create a custom hand-held controller for a a simple remotely operated rc car I am planning to make. I want a sending device to be able to read analog signals from my hand-held controller analog joysticks on several channels and have it be sent over wirelessly to the microcontroller on the car. I am aware that I can use IR, but I am unsure whether IR would allow me to send an analog signal so that I could, for example, change the speed of the motors. Also, I am unsure whether IR would be convenient since the led would have to be pointed directly at the IR sensor on the other end. On the other hand, I can use a hobby radio controller, but what I don't like is that it is very bulky and not very convenient for something so small. Radio is very convenient in the sense that you don't have to point it directly at what you're controlling in order for it to work and there is a large range. I also know that there is the Xbee, but those are relatively expensive. In my case, the cheaper, the better. Are there any boards that would let me have a radio transmitter with inputs from one microcontroller sending information to a receiver on another? What would be the best solution to this problem? Thanks for your time.

                                                                                                                            • Re: Have a question about radio or wireless communication?  Ask me!
                                                                                                                              Chris_Pinter

                                                                                                                              Is this a toy you are building?  Is it a small project for your own use or will you be selling the system?  I need to know in order to point to the right resources.

                                                                                                                               

                                                                                                                              I am not sure of your capabilities. So I need more info.

                                                                                                                               

                                                                                                                              Thanks,

                                                                                                                               

                                                                                                                              Chris Pinter

                                                                                                                              www.pinterec.ca

                                                                                                                                • Re: Have a question about radio or wireless communication?  Ask me!
                                                                                                                                  steved5517

                                                                                                                                  I believe that I have some supplies which can make a basic radio. As an aged hobbyist I just want to have fun and satisfy my curiosity.  My training as a physical chemist (graduated in the 1960s!) gave me a taste and respect for this wonderful field. I am impressed with the knowledge and support at this site. Thank you to all!

                                                                                                                                    • Re: Have a question about radio or wireless communication?  Ask me!
                                                                                                                                      shabaz

                                                                                                                                      Hi Steve, there is great enjoyment creating radios, so I hope you have a lot of fun. For AM type radios, the ZN414 IC was very easy to get going as a TRF radio, and was often a first radio for beginners. It is not made any more, but I noticed on e-bay there are some other manufacturer 'equivalent' ICs like MK484 and TA7642 being mentioned and available. Possibly they may work just as well. I think I did try MK484 once and it worked fine. It doesn't need any critical components.

                                                                                                                                      For FM, a very popular chip for hobbyists was the TDA7000 which again is obsolete, but is available from ebay. The circuits were not bad, reasonably simple, although eventually the channel drifted because there was no PLL. There are lots of FM receiver boards from (say) places like Sparkfun, they tend to be so integrated that very little is needed beyond the IC, so I suppose a lot of the fun disappears. They need to be controlled by a microcontroller using I2C, so it's no longer a purely analog design. For I2C controlled radios, I quite like the TEF6606 which is not bad quality (about the same as a car radio), better than the sparkfun ones probably, although slightly noisy compared to a home radio, and is also surface-mount whereas the old TDA7000 was available in the larger DIL package. For lots of fun with superhets, a popular chip is the NE602 or SA602, (it is pretty old though but still manufactured maybe), and a separate demodulator. So it would be a more larger circuit though.

                                                                                                                                      There would probably be more fun in an analog controlled circuit rather than the I2C controlled ones, I think even an ZN414 type AM radio is a lot of fun, and there will be lots of information on it, since it was so popular.

                                                                                                                                • Re: Have a question about radio or wireless communication?  Ask me!
                                                                                                                                  doumandji7

                                                                                                                                  We are an R &D group ARGEBILISIM established in Turkey ,working for a new project for our company which consisits of collecting UART data from end devices stations using Jennic wireless technology .Here is Joined our network sheme , we are making our tests on JN 5148 module via AN 1061,  we would like to ask your advice as network- jennic- jennet professionals  :

                                                                                                                                  -Does joined nodes end devices or routers should send automaticly their data to coordinator when they have data, is it  like CR already  scans its children joined automaticly one by one?  or  should we add in our program a scanning algorithm for reading one by one joined children if they have data so that all nodes don't send on same time their data to avoid loosing some of them, they will be given each one like its turn for sending its data,so that in one time  only one end device is communicating with coordinator?

                                                                                                                                  -If we have to make our scaning all devices method for collecting one by one node data to cr : how to extract the list of nodes that joined our cr : or our asscoiated network autorised nodes (all their  64 bits adresses)?


                                                                                                                                  Can you give us advises about jennic network CR and  ED global idea of how should be collecting data done via wireless for  safe trustable and fast ways of collecting data from end device stations,we could not find any suitable and understandable answers from forums or documetations.

                                                                                                                                  Thanks in advance

                                                                                                                                  DOUMANDJI.s
                                                                                                                                  Electronic Engineer
                                                                                                                                  OUR PROJECT .JPGwww.argebilisim.com

                                                                                                                                  • Re: Have a question about radio or wireless communication?  Ask me!
                                                                                                                                    rugrat01

                                                                                                                                    HI Chris i have an old valve ham radio Yaesu 901 D on the Rectifier A unit Board PB-1708 it has blown 2 Diodes vo6b 600v 1A recitifier silicone diodes which apparently are no longer in production oks Well my searching on the net has come up with a comparison of a  NTE116NTE116 or a Multicomp-1N4005 My question is will either of these replacements be ok in circuit or do i keep trying to find the exact original parts Any help in this regard will be of help as i dont wish to smoke the old girl up lol thank-you in advance for any advise that you may be able to give me.yours truly IAN

                                                                                                                                    • Re: Have a question about radio or wireless communication?  Ask me!
                                                                                                                                      jose2559

                                                                                                                                      Good morning Mr. Pinter!

                                                                                                                                       

                                                                                                                                      I was idly spinning around in my chair last night looking at my many remote controlled gizmos and gobs, when I was suddenly struck by an idea for a new project to work on: a custom "universal" 2.4 GHz transceiver.  I want to be able to switch control from my quad-copter to my RC car and back using presets (I'm planning on using an arduino for this), but I don't know how to approach tuning signals for the transceiver.

                                                                                                                                       

                                                                                                                                      Is there a way to "record" PPM signals from a 2.4 GHz controller so I can disguise my custom controller as the original?  I've seen it done for infrared signals, such as custom arduino universal remotes, but I haven't found any that work on 2.4 GHz channels.  The idea is to be able to program presets into my controller by having it record signals from the original controller.  Do you know of any software that can do this?  My problem is that I don't know what channels my RC devices work on.

                                                                                                                                       

                                                                                                                                      Sincerely,

                                                                                                                                      José Justiniano

                                                                                                                                        • Re: Have a question about radio or wireless communication?  Ask me!
                                                                                                                                          Chris_Pinter

                                                                                                                                          Hello Jose,

                                                                                                                                           

                                                                                                                                          Yes you can do It.  I have done it before myself.  Ofcourse you will need a Vector Signal Analyzer (VSA). You can pick you up for $150,000.  Sorry not available at Radio Shack.

                                                                                                                                           

                                                                                                                                          I would suggest building a programable controller that you can enter seneral RC codes into manually.  Then you can switch from one toy to the next.

                                                                                                                                           

                                                                                                                                          Hope this helps,

                                                                                                                                           

                                                                                                                                          chris Pinter

                                                                                                                                          www.pinterec.ca

                                                                                                                                            • Re: Have a question about radio or wireless communication?  Ask me!
                                                                                                                                              jose2559

                                                                                                                                              Hello again Mr. Pinter!

                                                                                                                                               

                                                                                                                                              Thank you for your quick response!  Yeah, the Vector may be a little out of my price range.  However, I've seen slightly more invasive ways to hack a radio receiver so the arduino can read PPM streams:

                                                                                                                                               

                                                                                                                                              RCArduino: How To Read RC Receiver PPM Stream

                                                                                                                                              In this case, arduino is integrated into the rc device itself for added functionality.  My goal is a little different: I want to integrate arduino into the controller, I could possibly program some complex maneuvers into the arduino to execute on command (quad-copter backflip for example).

                                                                                                                                               

                                                                                                                                              Do you think something like this could be done with a transceiver?  Granted, it's not as magical as a 2.4GHz universal remote, but is there a way to gut existing controllers to find out their channels and PPM streams?  Or would I need to surgically remove the IC along with the transmitter and hook my arduino to the IC?  I'll have to stick with IR for the universal controller, but maybe I can still switch to known 2.4 devices.


                                                                                                                                              Thanks for your insight!

                                                                                                                                              José Justiniano