I'm not sure I'd call a controlled stream of electrons moving through a vacuum primitiveAs I stated at the end of the message, I want to stay on the primitive side to demonstrate how basic this thing can be. I don't want to use any solid state devices.
Congrats on your success!I am well aware of the limitations of crude radios and speakers but I am fascinated by the origins of the polished and efficient gadgets we have now. I like getting to the roots of these things and by constructing them get a feeling of discovery and satisfaction that the originators had. As for 10 year olds posting on instructables, that is the exception rather than the rule. The site is rife with things of amazing complexity. As for the foam plate speaker, it sounds pretty good! There is a video & audio of it w/ Kip Kay on Instructables.
I'm not experienced at all with most types of amplifiers. I do more work with digital systems than analog ones. I know my basic op-amp circuit, but that's about it. But I'm sure the guys here can help youMatt,
Thanks for the reply. I don't have a video of this thing working but I think I'll do one. I found it strange that I didn't get the expected high voltage at the speaker wires. When I do the video, I'll also demonstrate that anomaly. I'll need to research how to post videos on this site.
Since you seem very knowledgeable about this subject, do you have any recommendations for building another stage of amplification(with a tube) to allow the feeble output of a crystal set to increase with enough (undistorted) gain to drive the input of this rather bizarre amp to a level that can be heard without difficulty?
AG, I think you misunderstand the idea of this project. It's not supposed to make a nice, clean, clear output. It's just supposed to be a fun thing to do with unorthodox parts. It's more of a novelty sort of thing. It's much like my tesla coil, which I built out of garbage. It's not supposed to work as well as a tesla coil with brand new parts, calculated sizes, shapes, voltages, currents, etc. It's just fun to make something with stuff that nobody else would think would workYour weird amplifier with the wrong high voltage supply and the wrong output transformer has a very low maximum output power. Increasing its input with more voltage gain simply increases its distortion without making it louder.
You need a real amplifier driving a real speaker.
That's my point exactly! It's garbage. Nobody would expect ANYTHING pulled out of a trash can to play ANY sounds at allNo bass. Bass is very low audio frequencies. A speaker without an enclosure has the low frequencies from the rear come around the speaker and cancel low frequencies from the front. The foam speaker is garbage.
Good for you. But you're still missing the point.I never made anything out of garbage that was crude and primitive with horrible performance.
Everything I made with normal parts performed very well.