I watched this YouTube video where the author shows his FM transmitter using a big 60 volt power MOSFET. He also shows a very readable photo of the schematic. The video was made several years ago in 2012. He is powering this transmitter by connecting it to eleven 9 volt batteries in series, totalling 99
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I went online a few days ago and looked for some odd RF transistors, but instead I was shocked. Almost all of the parts I’ve been using are through hole parts, like transistors in a TO-92 package with wire leads. I looked at a few distributors such as Mouser, Avnet, Arrow, Digikey, Newark. I found
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I was reading some of Geo John’s projects and came across a crystal radio set that he built using two tuned coils. A crystal radio set refers to the type of detector used, which was once a galena crystal and a ‘catwhisker’ to find a sensitive spot on the crystal. Nowadays, that is no longer
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I captured this off a video and tried to make it a bit more readable. I think it was from Sanjev. I built it and it does work at 40 millivolts. The 2SK170 JFETs are not common, and may be difficult to obtain. Other JFETs can be used, but I haven’t tried them. I wrote
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Fellow JT experimenter Quantsuff has been experimenting with a Joule Thief using the 2SK170 JFET, and it runs at 131 millivolts (0.131V), powered by a solar PV cell lit by a table lamp. This is a very good JFET for low voltages; I made a similar circuit a while back and it ran at several
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I built a Joule Thief using a 2N7000 MOSFET with the white LED across it, a standard coil (see below) and a voltage divider connected to the gate. I was trying to find out more about the MOSFET, such as the gate bias voltage needed to make it run on a 1.5V AA cell. The
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I blogged a schematic on May 15, but it took me until now to build the schematic. I tack soldered the PSO together with the components shown, except I did not use the two diodes and two 10k resistors. First off, according to this article, to get it to oscillate, the overall voltage gain of
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I ordered some IRLZ34 MOSFETs from Futurlec and they finally arrived, shipped from Hong Kong. I took one out of the bag and it was marked IRFZ34. What!?!? I ordered IRLZ34, not IRFZ34!! I took the rest out of the bag and I counted 33 of the IRFZ34, and 2 of IRF9Z34, which are not
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The Youtuber going by the name of Sanjev21 has read my comment about using the TN0702 low gate threshold MOSFET for a Joule Thief that will start and run below 0.6V. He replied that this has a Rds(on)of 4 ohms at 2 volts, which is “too high”. The problem is that he is using a
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I received the following comment from Mayank and this is the reply to his comment. Hi Watson, I have a 1V, 3A solar panel that I want to use to charge 6V SLA battery. I checked some other circuits on the web and they use big torriod cores with 2N3055 transistors. Can I use a
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