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  For many years this has been my soldering iron. I have liked it and continued to use it because it gives me a choice of a high 40 watt and a low 20 watt heat setting. I also like the variety, durability, and economy of the tips that are available for it. Here is a link to the type of tips that are used. It is manufactured by Weller but I am pretty sure that it was an Ungar design originally.   http://www.newark.com/weller/pl113/tools-soldering-tips/dp/33F681?ost=Weller+Solder+Tips& ...
I have been fighting with the wire that connects my solder iron to its station. It is always in the way. If I have meter leads or test clips on the circuit the solder iron wire drags across them and pulls them loose. It catches on parts and hardware around the build site and makes an already bad mess worse. While there have been some attempts to produce a wireless iron I have not been impressed with them. When it comes to soldering and desoldering nothing can replace the regular wired iron.  ...
Earlier today in a blog post  http://www.element14.com/community/community/design-challenges/vertical-farming/blog/2015/08/16/use-of-leds-in-vertical-farming I volunteered to try to capture the spectrums of some of the common LEDs. The discussion in that thread had been about the effectiveness of LEDs as grow lights for the Vertical Farming Challenge. I have a cheap spectroscope that I got to show the grandkids about how we can know the elemental composition of things by looking at their s ...
Throughout most of my life I have been a scavenger. My eye is always peeled and on the lookout for that little bit of technology that I might be able to use someday. As a boy one of my favorite things to do was to walk along the curbs in the small city where I lived and pick up the small screws and bits of metal that I might find there. This tendency to be on the lookout for materials that just might be needed someday continues even to today. I want to tell you about one item that I found that h ...
This project build and subsequent test of batteries was inspired by shabaz who several times in the last couple years, has brought up the question of which battery is better, E***, D***, or some other less expensive option. I was also eager to use my newly built DC Load unit for something more important than rack decoration.   The project build itself is an adapter that uses a bench power supply to power its internal circuitry, the new DC Load unit to provide a constant current load, and a ...
I have made 5 very short videos of the final testing of the DC Load Unit. I usually don't make videos as I have a voice problem which makes it difficult to understand me. That being said, here is the first video  in which I track the stability of a load of 1 Amp as I bring the unit from about 25 Volts down to 0.7 Volts. One limitation which I have had to deal with in these tests is that my bench supplies do not have the power to completely push the load to its limits.       ...
The progress on the DC Load unit has raced well ahead of my progress on this blog. As is my nature once I get involved it is hard to stop working. Fortunately I did remember from time to time to stop and take some pictures. In this next to last blog I will post the most recent revision of the schematics and show pictures of the completed boards and write a little bit about the things I learned. Here is the final Main Board Schematic and picture of the board before and after mounting it in the un ...
Last night I was doing the preparatory work prior to the assembly of the final board for the DC Load. This is the board that handles the limits I want to protect like: Over Voltage, Over Current, and Reversed Polarity. I bread boarded the circuit that I presented to you in Episode II Schematics. To my dismay I found that it was not working as I had planned. Since my initial design and bread boarding I had made minor changes. Also my expectations for this circuit had also expanded. Finally it see ...
In this blog post we will talk primarily about the collection of materials needed for the Load Unit and how they are assembled to make the frame work for the electronic boards and wiring that will follow. I began by selecting a suitable enclosure, which in this case was the case and chassis from an old piece of Dental Equipment called a Cavitron. Here is the unit's housing before and after it was stripped of the original electronics and fitted with a new front panel.       Al ...
In this blog posting I will publish the schematics for La Carga DC Load unit. I will also add some commentary to aid with the interpretation. My style of drawing schematics has evolved some but the roots are back in the 1960s. If you find anything of brilliance in these schematics it probably came from the tutorials of peteroakes, the engineering in depth wisdom of michaelkellett, the innovation of shabaz, or any other of my mentors who have helped me so much these last two years. In many ways I ...
In January of this year, inspired by some of peteroakes 's excellent tutorials I decided to begin to design and construct a DC load. I have been learning and improving my electronics ever since joining E-14 about two years ago. Those of you who are familiar with me know that I tend to be a little retro and basic in my approach to problems and projects. This DC Load unit which I have dubbed " La Carga " (named chosen by 4ringfan) will be no exception. Up until now I have always been satisfied to ...