A 41 min. YouTube video shows operation, tears down, and explains the components. It seems that they are made with cheap chinesium components that are too low voltage ratings so they will fail prematurely if the HVDC is left on a long time or if the spark gap is too wide. Schematic from video is
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Some important information for those who wish to power their projects with a USB C “power delivery” adapter. You may need one of these. This is a YouTube short video.
This may be helpful when choosing the amount of capacitance for a certain unregulated AC power supply – the kind that uses an old fashioned transformer. It calculates one variable given the others. https://www.chipbuilder.com/full-wave-power-supply-ripple-calculator.html
Here is a wealth of information about much of the electronics that is used by government entities especially the military. You can find out what the system is for data processing hardware. This used to be called JAN – Joint Army Navy. https://en.m.wikipedia.org/wiki/Joint_Electronics_Type_Designation_System
I posted the photo of the back side of the receiver (earpiece) for a Bell System telephone (either 500 or 2500) set. I said that the green blob in my photo (and the ’44A’ metal can in the wikimedia photo below) was used for reducing the volume of loud signals. Well, that’s only slightly correct.
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Me and my high school friend made a DC to DC converter that would give us 30 or so volts at a couple amps from a 12 volt battery. We used germanium power transistors which could not go much above 10 kHz. The Delco’s and the 2N458A’s were our favorites – we managed to push
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A month or so ago a guy posted a plea on the Facebook group that he had these pallets of these 12VDC, 1.5 amp switch mode wall warts and he was desperate to get rid of them or he would have to throw them in the trash. He said he would take any reasonable offer
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I have a PIR (passive infrared) motion sensing light on my porch for more than a year, and I’ve noticed that it can sense some of the cars that go by. If the car has been running, like coming home it will usually trigger the light. But when a neighbor starts the cold car and
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From a comment I left in Big Clive’s youtube video https://youtu.be/jgaCYRc1-og In the past I’ve seen Clive having to replace “used up” capacitors in the ‘capacitive dropper’ circuits of low cost line operated devices. The problem seems to be common in other countries but here in the US I haven’t seen any problems with the
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The main reason I joined Facebook was to interact with others who shared my vocation and avocation, Electronics. It’s been a part of my life since I was very young. More than five years ago I joined several FB groups dealing with Electronics. During those years I have been banned from several groups not because
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