I had already built one of these several years ago, and since I’ve used it to test the crystals that I’ve salvaged. It’s a simple circuit, using only a single transistor to make a Colpitts Oscillator with the two leads for the inductor run to terminals so that various inductors and coils can be connected
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If you open up a cheapo 9 LED flashlight you will find that they put 9 LEDs all on the same PC board and they are all connected in parallel. How do they do this without having the LEDs burn out? For decades, the engineers have warned us that you should never connect LEDs in
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Paul posed a question about the base resistor and how it affects efficiency. This is a point that was apparently addressed by the low Vce(sat), high gain transistors that were made especially for DC to DC converters. Since the BJT (bipolar junction transistor) is a current operated device, the current that it needs to turn
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My “rival” Flagiusz has done some experimenting with a version of a Joule Thief which uses a capacitor similar to my Supercharged Joule thief, but is simpler. He also claimed that it was a bit more efficient than my SJT. This version, which he calls Fast Joule Thief, is the second one after the ‘basic’
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I measured the voltage of an unused Energizer Lithium AA cell, and found that it was 1.806 VDC, and another one measured 1.807V. Wow! Looked like the Energizer Bunny was running on jet fuel! These are very potent batteries. Their voltage is 20 percent higher than the normal AA cell. These lithium cells are supposed
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