Here is a writeup from another radio enthusiast about his newly purchased Mega 328 uC based component tester. They come in handy for testing electrolytic capacitors especially for ESR – equivalent series resistance. The tester will also test silicon and germanium transistors, handy for making a judgment on how leaky it is. I have a
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This is from Electronics Illustrated Projects 1968. It shows crystal sockets, but instead a RF coil may be used and its value will be about 220 microhenrys. And C1 and C2 will have to be changed to bring the frequency down to the AM band. The germanium transistors are no longer available so silicon transistors
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From fb group Decades ago I bought a 100W, 28V big old soldering iron for a dollar at a garage sale. I have it connected to a big old unregulated power supply. It works good for the very seldom times I need that much heat. I could do stained glass windows with that beast!
From FB group Building Transistor Radios, Aug 6 This also happens with the meter movements of old analog meters. The iron particles get into the magnet assembly and stop the coil from moving. The only way I’ve found that gets rid of the iron particles is to very gently put a thin piece of steel
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Also photo posted to FB group Building Transistor Radios. I got several of these Wien Bridge Oscillator kits from an eBay seller in China. They are built using the circuit from http://redcircuits.com/Page13.htm More information can be found on the wiki for this oscillator. The kits come with no instructions, so to assemble it, use this red circuits
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From FB group Hobby Electronics When a manufacturer purchases parts for the product they are making, they expect to receive what the engineers department had specified in the department’s documents. When the parts are received, the Quality Control department is supposed to check to see if the parts received meet the engineering documents. I know
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For FB group Building Transistor Radios When I started building regen receivers, the first thing I found I needed was a simple signal generator. I have a function generator, but every time I want a different frequency, I had to readjust the controls. So I built a few RF oscillators to put close to the
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Also FB group Building Transistor Radios When I was a teenager, my high school friend and I worked for a guy who had acquired many thousands of dollars worth of test equipment. We used equipment with famous names such as Hewlett Packard, General Radio, Boonton, Fluke and many others. In the army, it was the
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From FB group Electronics Hobbyists, regarding the Zenith Royal 500 radios. Clyde Hendrickson There are two 50 uF, 10V electrolytic capacitors under the battery holder. Replace them with 47 uF, 10 or 16 volts. There is also a smaller capacitor next to the other, it might be a 3 uF, or a 16 uF, 10V.
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From FB post about Arduino driving a ‘HC595 chip. You don’t need an oscilloscope to see digital signals. If you slow down the speed, you can see what’s happening by looking at LEDs. Everything is digital, just on or off. Plug two red LEDs, transistors, and current limiting resistors for LEDs (330 ohms), and for
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