He has a strong Aussie accent, a bit hard to understand. It’s a 28 min. YouTube video. He says BD139s have a fT of 250 MHz, but the datasheet I have does not specify any fT because the D in BD139 means they are a low frequency device, not meant for VHFs or RFs in
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This 2.5 min video uses a SS8050 transistor which is not very good for a 100 MHz oscillator. https://www.facebook.com/reel/347155875050146?mibextid=9drbnH&s=yWDuG2&fs=e
A basic one transistor regen receiver uses an MPF102 JFET to give the regenerative gain. Also uses two transistors to amplify the audio to drive an earphone. https://www.circuitbasics.com/what-are-fm-receivers/
This is a long article but a very interesting project. It uses HSMS-2850 Schottky detector diodes in a discriminator. He uses WE 1200 ohm sound powered headphones. He’s Canadian. https://electronbunker.ca/eb/FMCrystalSet.html
I’m sitting on the grass in the back yard and it’s chilly, but the sunlight feels really good on my back. I can hear some birds up in the trees, I’m waiting to see if they’ll come down and eat some birdseed. I started thinking about a way to watch them up there. What I
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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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This is a low power oscillator using an air core coil and silver mica capacitors for stability. Parts values are subject to the frequency needed. There is no modulation. For FM the 10 pF capacitor would be lower and include a reverse biased diode as a varicap in parallel. The audio should be across this
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Well, this article wants the Flunked Clown College to let DRM be one of the choices. It doesn’t matter to me because I don’t plan on spending anything on getting a device that will decode HD radio, FM or AM. Even if the next car I buy has it, I will still not be using
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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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