He uses my SJT circuit in his web page. https://devopedia.org/joule-thief-circuit
Archive for the ‘Joule Thief SMPS DC-DC’ Category:
2020-02-21
I found that 100 uH was a good all around value for these solar garden light circuits. But at the time I made these around 2009 the 5252 4 legged chip was uncommon and almost all the garden lights used 2 discrete transistors. I don’t know why they started using the 4 legged 5252 –
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2018-01-22 Demo Of Wireless Charging
for FB group Electronics Hobbyists The demonstration of a wireless charging circuit that I built uses a Joule Thief circuit with two yellow LEDs in series. The coil is a hand wound loop about 75 mm or 3 inches diameter. A second loop of gray wire with a white LED (dimly lit at bottom) is
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2017-08-19 Emitter Base Breakdown Can Damage Transistor
From YT reply to Neilgn 2017-08-20 Take any NPN transistor and measure the gain, and write it down. Then put a 1k resistor in series with the transistor’s emitter and connect the emitter to positive and base to negative of a power supply. Adjust the voltage until 2 or 3 volts are across the 1k
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2017-06-08 AD Has ADP5090
Ever since I’ve been experimenting with Joule Thiefs I’ve done so with the intention of using the circuit for boosting a low voltage source to power a higher voltage circuit. So I think this Analog Devices ADP5090 is very useful for doing just that: powering circuits up to 200 mW from very low voltage power
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2016-10-18 FM Transmitter Uses Power MOSFET
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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2016-10-04 Joule Thief Powers Field Strength Meter
There are many circuits that are used infrequently that are powered by the usual 9 volt battery. One of these happens to be a field strength meter (FSM), which is used for detecting the power output of a transmitter such as the one a radio amateur uses. Some FSMs are very simple and use no
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2016-09-28 Battery keeps Joule Thief Lit
I put this AA cell, which measured 1.3 volts – ‘dead’ – on one of my germanium Joule Thiefs more than a week ago. It was glowing very brightly for a few days. For the last few days, it has been weakly glowing, and the Kirkland AA cell is still hanging in there, even though
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2016-09-06 Supercharged JT Shutoff
I had a hard time editing the reply to #2 of the comment, besides it’s a good blog. The following applies to my Supercharged Joule Thief. But you really don’t need to use a MOSFET. Any PNP transistor, 2N3906 or BC557, will do the job, and the current will be relatively low. Replace the diode
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