The lifetime of incandescent and LED lights is extremely dependent on the temperature at which they run – for incandescents, GE says it’s the inverse of the 7th power of the voltage – the voltage increases and the lifetime decreases. In the case of LEDs the problem is most designs sacrifice thermal management to get
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Homemade Adjustable Capacitor I read that the 365 pF air variable capacitors are very expensive, $30 or more so I decided to try to build one. It’s not difficult to make an adjustable capacitor out of materials one may have at home. This one does not adjust easily, it’s more of a prototype. I got
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Caps Wiki – a place for you to share your repair notes. I like the idea. I’m wondering if I have the patience to spend the extra time. https://hackaday.com/2022/02/24/caps-wiki-place-for-you-to-share-your-repair-notes/
Blinking LEDs are usually reset by the voltage dropping to zero then coming back on. So if one LED, probably the fastest one, blinks first, all the rest in the series string will be reset, then comeback on again when the fastest one comes back on. So you have essentially a single blinking LED and
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A string of LED xmas lights had been fritzing on and off, then it finally failed. I had to pull out 4 lights before I found two that were dead. I had to file off the ridge around the base to get them to fit properly into the base. So it’s back working again. It
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MP3 Player To FM Radio Link (Mono) This circuit allows you to play your MP3 or any stereo audio source into a mono signal for reception on an FM radio. It has no antenna and has a range of a dozen or so meters. It operates off a 6 volt rechargeable Ni-MH battery pack but
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I also remember those projects that used the CK722 and 2N107. The last few years I have been repairing older transistor radios with germanium transistors. I have had a few of them with bad germanium output transistors, and I’ve replaced them with silicon PNP transistors, along with a change in base bias resistors. They work
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This is a 5 transistor ESR meter for testing capacitors. https://eevblog.com/forum/projects/5-transistor-esr-meter-design/
