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Ralph Yamamoto's Blog

29 posts
I'm starting to get some experience with my CNC router and quickly learning that there are so many variables due to material, cutting tools, and individual machine capability that there will be quite a lot of trial and error.   As with most tools,  the only real way to get more proficient with them is to use the tool for an actual project.   I'm still looking for a tool flow that will work well for me.  I recently got an RPi4 and I 'm going to try to use that as my work ...
ralphjy

Finally got my Pi4

Posted by ralphjy Top Member Aug 21, 2019
I wasn't lucky enough to win an RPi4 in the Win a Raspberry Pi 4 in Celebration of Our 10th Birthday! contest and I didn't have time for a roadtest, so I decided to wait until the 4GB versions became widely available.  I started seeing a lot of them on Amazon, so I bought one along with an Smraza case which came with a 3A USB-C power supply and a fan and heat sinks.  I just got it on Monday.  I downloaded and flashed a 32GB uSD card with Raspbian Buster and got everything assemble ...
ralphjy

TPL5110 Nano Power Switch

Posted by ralphjy Top Member Aug 20, 2019
While building my recent LoRaXes project I realized for successful battery power operation that I need a way to remove and restore power between data transmissions because the components that I was using did not have adequate sleep mode functionality.  I found numerous references to projects using the TI TPL5110 Nano Power Switch to provide that functionality with Arduino compatible boards.  Adafruit and Sparkfun both carry TPL5110 breakout boards.  The Adafruit board is just a bi ...
I had a minor victory on my road to figuring out how to use my new CNC router.   I received the 0.5mm carbide end mills that I bought on Amazon and used one to successfully shorten a proto PCB that I need for my LoRaXes project.  The mill has about 4 mm of cutting depth.  The PCBs that I'm cutting are nominally around 1.6 mm thick.  Not a very impressive looking cutter but it worked.  I increased the spindle speed to 3000 RPM and reduced the feedrate to 80 mm/min and se ...
ralphjy

Genmitsu CNC 3018-PRO

Posted by ralphjy Top Member Aug 8, 2019
I've had great success with my inexpensive AnyCubic 3D printer that I got on Amazon Prime day, so I finally decided to get myself a low cost (under $200) CNC mill. I wanted to get something that would allow me to drill holes with reasonable accuracy and also mill PCBs.   I settled on the SainSmart Genmitsu CNC 3018-PRO.  It has an XYZ working area of 300x180x45mm which is sufficient for most things that I do.  It uses GRBL rather than Mach3 control firmware but I think that s ...
After a fair amount of frustration trying to fix the hotend/extruder on my Velleman K8200 3D printer I finally decided that I should just go ahead and buy a new printer.  I really like the K8200, it has a large build area (20 x 20 x 20 cm) and has worked reliably for 6 years.  But recently I've been having lots of problems with it.  I think it started with some bad filament.  I kept getting jams in the Delrin isolator in the extruder due to expanded filament.  I replaced ...
ralphjy

LoRa Gateway Activated

Posted by ralphjy Top Member Jul 6, 2019
It has been a while since I received The Things Network (TTN) LoRa Gateway and two MKR WAN 1300 boards for winning the IoT in the Cloud challenge.  I've been busy with roadtests, but really would like to start playing with LoRa based sensors.  I checked in my local area and there are 5 gateways listed on the TTN map.  One is a Things Gateway like mine, two are homebrew (RPi/Arduino) and two are unspecified.  The closest gateway to me is about 4 km away as the crow flies.  ...
I just received my prizes for the Project14 IoT: In the Cloud Competition.  I received a 915MHz LoRaWan Gateway to the Things Network. In addition I received 2 Arduino MKR Wan 1300 boards and a MKR SD prototype shield.   Looking forward to experimenting with LoRa.  Thank you to Element14 and the Community!   Ralph     ...
I just attended the the one day NXP Technology Days conference in Seattle, WA (actually in Bellevue). It was held at the Meydenbauer Convention Center.  This is the first Tech Days conference that I've attended.   In the morning I attended an info session on the iMX 8M (multimedia) family of processors.  The Mini and the Nano are newer and the Mini is available now with the Nano coming out in 4Q of this year.   After the info session I attended a hands-on workshop for t ...
I was inspired by jomoenginer and ordered a Jetson Nano Developer Kit directly from Nvidia.  I received it a few days ago but just now had a chance to set it up.   I noticed in YouTube videos that everyone uses the 4A power supply with the barrel jack.  I guess I should have checked earlier.  The default standard power mode is 10W.   It is supposed to be marginal with the 2A micro USB jack. There is a 5W power mode that you can select that reduces the CPU and GPU ...
Since this power supply has been around since 2015, there is a lot of information about it on the Internet.  I thought some on the info that I've come across on the internals of the power supply might be of interest to others.  I don't think this info is appropriate for a road test so I'm posting it on my personal blog not the road test blog.   A couple of caveats about this info: I would not suggest that anyone open or modify their power supply as that will definitely invalidat ...
ralphjy

Phones for the Elderly

Posted by ralphjy Top Member Apr 16, 2019
I'm writing this out of frustration of trying to find a simple phone for my 96 year old mother.  Going through the aging experience with my parents, other relatives, and parents of friends, has made me realize that appliances that are designed today are much too complicated people with diminishing capability to operate.  Let me use the phone as an example.   My mother lives in Hawaii and I live in Oregon (having moved 40+ years ago for an engineering job).  My mother was liv ...
I've wanted to try using a laser cutter but haven't had the opportunity until today.  There is a campus of Portland Community College (PCC) just up the hill from me.  Spring term was the first time that they've offered Maker community education courses (3D printing and laser cutting).  I was fortunate to get into the first laser cutting class.  They have 3 laser cutters from Universal Laser Systems in their MakerLab.   They have a 60 Watt model with a work area of 3 ...
I received a notification that NXP is doing a Technology Training Day in Seattle (Bellevue), Washington on May 7. https://getregisterednow.com/NXP/Event/Register/Register.asp?e=NXPTechDaySeattle2019&r=e&elq_mid=7369&elq_cid=2769005   Has anyone attended one of these?  And anyone going to this one?   I'm down in Portland, so I'd probably need to drive up the day before and stay overnight.  I'm still debating whether to register or not.  I'm sure the worksho ...
I was very excited to try out my Oboo Smart Clock. I really wanted to demonstrate some of the features to my wife who wondered why I would back a clock on Kickstarter.  Unfortunately, the out-of-the-box experience was not very good.  The instructions included were minimal, which would have been fine if everything had functioned correctly.  They have a browser based app (not a downloadable mobile app as the instructions imply).  The app is not well designed and because the scr ...