From Talking Electronics. I’m not sure if this circuit can be frequency modulated the full amount for the FM broadcast band. It’s difficult to push a crystal off its resonant frequency. I’ll be trying it someday if I can find the right xtal. I would be more inclined to instead use a ceramic resonator. I
(Read More…)
I got this idea; instead of using a microphone and preamp at the end of a twisted pair, I would build a microphone, preamp and modulate a red laser with the audio and pick up the audio about ten yards away with a light detector. Notice that it runs on two 2V photovoltaic cells in
(Read More…)
Big Clive tears down and reverse engineers a Philips ultra efficient light bulb. It’s 60 watts equivalent but draws only 4 watts. It has a color rendering index of only 80, and costs about ten Pounds UK or about $13 US. This uses 8 filament strings of LEDs and the filament string drops about 200
(Read More…)
They claim that their Laser Fusion demonstration is working. Uses boron and hydrogen. https://newatlas.com/energy/hb11-laser-fusion-demonstration/
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
(Read More…)
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
(Read More…)
LED streetlights are decimating moths in England. The LEDs have blue light which insects use to see. The moths are pollinators like bees plus they’re food for many animals. There are a number of solutions for mitigating the problem. The blue light can be filtered out, among other things. My thinking is that the streetlights
(Read More…)
Clive tests three UV-C germicidal lamps to see if they are really putting out UV-C sterilizing light in this 3 minute video. He uses the green banana test. It’s obvious how the cheap LED lights don’t put out any germicidal UV-C. The UV-C wavelengths are blocked by regular window glass or the clear epoxy used
(Read More…)
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 –
(Read More…)
From FB group electronics hobbyists Over the holidays I installed two solar 60 LED lights I bought on eBay. They stopped working just a few weeks after. I finally got up on the ladder and took them down to see why they died. Well, spit! The solar panel is plugged into the jack on the
(Read More…)
