From FB comment in group Vintage Transistor Radios I think we like the look of wood because of some primeval instinct from our distant past. Perhaps it has something to do with the trees being protective, under which we could take shelter during rain or shine. Or perhaps those prehistoric people who survived longer
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I was reading this blog, and I’m referring to this schematic. The author calls this regenerative receiver a “minimalist” design, but I refuse to consider a circuit with 7 transistors minimalist. If one thinks of the design as constrained to using a supply voltage of only 1.2 volts, a single AA or AAA rechargeable NiMH
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I ordered these kits Several weeks ago and they finally arrived today. I opened up the package and found several parts rattling around loose in the box. I found one bag had been cut open, and whoever slit it didn’t tape or staple it closed. I got to work and assembled one of the kits
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The previous regenerative receivers I’ve built have been 27 MHz, but they have not been successful, they haven’t received a decent verifiable signal other than the very strong one I made with a dip meter. So this time I would build a regenerative receiver that is much lower frequency, and I chose 10.000 MHz because
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I pulled a pill bottle out of my junk box, it had a single layer of solid enameled wire wound on it, and it measured 85 microhenrys. So I added the transistor, resistors and the capacitors to get it to oscillate at the low end of the AM BCB, around 540 kHz. The schem is
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I got these today in the mail. Notice the temporary wire I poked into the connector. I ordered some adapters but I haven’t received them yet. I bought a frequency counter with the rubber ducky antenna but it doesn’t have the sensitivity that this cheap one has. I got two of these for $28, free
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I’m building a tuned circuit tester, which is a Franklin Oscillator without the parallel tuned circuit. I based it on the schematic I found at this URL. The first amp is a JFET in common drain or source follower configuration, which then drives the 2nd stage, a PNP transistor in common base configuration, so there
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When I googled I found a ‘stereo input’ FM transmitter. Most of the FM ‘bugs’ on the web and YouTube have a microphone. The circuit I linked to has left and right inputs, but mixes them to make a monophonic (not stereo) signal. After looking at the schematic I noticed a mistake, so I thought
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I have always thought that using ferrite toroid cores for radio projects at HFs and above was not necessary, because all of the RF circuit parts lists call for low permeability powdered iron cores. I’ve never given it much thought; about the only thing that crossed my mind was that the powdered iron cores may
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I was reading some of Geo John’s projects and came across a crystal radio set that he built using two tuned coils. A crystal radio set refers to the type of detector used, which was once a galena crystal and a ‘catwhisker’ to find a sensitive spot on the crystal. Nowadays, that is no longer
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