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/
Archive for the ‘Building projects and kits’ Category:
2024-03-30 MX20T Link Switch Port Tester
A long time ago when we were going to Cat5 UTP, I had a lot of these MX20Ts left over. So I made up a 15 pin plug with the negative 9VDC on pin 6 and positive on pin 13, and soldered the wires to the battery contacts. I taped the battery to the back
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2024-03-29 FM Crystal Set Uses Helical Resonator For Tuning
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
2024-03-24 Signal Distortion From High-K Ceramic Capacitors
A good article about signal distortion in a Butterworth low pass opamp filter using C0G and X7R MLCCs. https://www.edn.com/signal-distortion-from-high-k-ceramic-capacitors/
2024-03-22 USB Power Delivery Trigger Adapter
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.
2024-03-11 Flexible LED Filaments
Some information on what current and resistors to use. The LEDs are all in parallel and need about 3 Volts, current limited with a resistor. https://www.facebook.com/reel/909951727389682?mibextid=9drbnH&s=yWDuG2&fs=e
2024-03-10 Radio Shack P-Box List, Assembly Manual, Schematic Info
This seems to be pretty much all of the kits. http://my.core.com/~sparktron/pbox.html
2024-03-09 Big Clive’s Old Tungsten Roadwork Beacon – Barricade Flasher
I built this “tungsten roadwork beacon” as Clive calls it, using the parts given in my schematic (photo below). I didn’t have a 6V, 90 mA lamp, so I simulated it by using three 20 ohm, 1/4 Watt resistors in series, which gives 60 ohms and 100 mA load with 6VDC. For an indicator I
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2024-03-08 Some Rube Goldberg Inventions That Could Make Some Cool Projects
Mostly wood. Short video. https://www.facebook.com/reel/1099537448068091?mibextid=9drbnH&s=yWDuG2&fs=e
2024-03-08 FWBR Ripple Calculator Online
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
