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
Archive for the ‘Electronic Components’ Category:
2024-03-26 HVDC Module Teardown, Operation And Explanation
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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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 The 555 Chip Under Microscope
The NE555 and some interesting information about it. A YouTube short by @Evilmonkeyzdesignz.
2024-03-15 Ferranti Argus “Hearing Aid” Computer
In the “Original Series” chapter this very interesting Wikipedia article talks about the “hearing aid computer” that used the OC-71 germanium transistors which were used in hearing aids and could go only up to 25kHz clock rate. That was quite slow – tube computers could clock at 500kHz. Later models used faster transistors and could
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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 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
