|
Howard,
toggle quoted message
Show quoted text
On second thought, your modules could be a fine way to teach radio. Modules start to make a lot of sense as radios become more complex. Many who design radios for a career have created their own modules to play with new concepts. As you suggested, a DC receiver could be busted down some. Perhaps demo a very simple diode detector with hi-z phones for local AM stations.. Then a bare bones SA612 (with 9v battery, coil+cap for LO, hi-Z phones, wire antenna). An inductor tuned with a brass screw for the LO is cheap and approachable. Same rig could hear your 40m transmission by adjusting the LO coil and cap. Then add an audio amp, RF gain pot on the antenna, audio gain pot, RF filter, RF amp, AF filter, a back-to-back diode audio limiter, a stable si5351 vfo. From there, perhaps a second SA612 and a crystal IF filter, agc,? audio into an RPi. Spend the remainder of the hour showing how to code DSP algorithms in python. I might want to play with all that once you're done with it. Jerry, KE7ER On Sun, Dec 8, 2019 at 08:12 PM, Jerry Gaffke wrote:
|
