alt Hacker NewsA friend and I have been trying to build an AM radio. We got a few working, like the basic "crystal" (germanium diode) one with an earpiece, generally picking up 1 or 2 stations very faintly. Then some attempts with an AM radio IC (TA7642), some that use a couple diodes and LM386 op-amp but they're generally terrible, if they work at all. It seems that following random schematics off the web or a youtube screenshot doesn't work very well.
I do have an RF design book I haven't started (by Chris Bowick) as well as this PDF now, which should be even more practical, so I'm hopeful I can figure it out. I also have some test equipment such as nanoVNA, tinySA, and an oscilloscope which makes it possible to get visibility into how stuff behave beyond "I don't hear anything; no idea what's wrong." I was able to see how the tank circuit was behaving as you tune it.
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Ronald Quan’s Build Your Own Transistor Radios is pretty good but I have only read it, not built any of the radios in it.
The Bowick book is solid for fundamentals like impedance matching and basic filter design. The old brown edition is more concise than the new one.
I worked through this [1] book (PDF) as a child, everything worked fine but have no idea if component availability has changed.
[1] https://www.worldradiohistory.com/BOOKSHELF-ARH/Technology/M...