Recent content by Mark Palmer

Thanks again, all. Another question related to tuning. The slider or wiper bar is apparently a crude tuning method. I think I will modify this build to install a tuning capacitor. I have this one rated at 365 pF, intended for crystal radio use. It has two solder terminals on each side.The...

I have another question on the diode. In reading up on diode technology, I see it is directional. Does this apply to the crystal radio? The right side of the coil is connected directly to the diode.

Thanks again, all. I am obviously new to this, and my "research" into the area comes up with a lot of variables. The conductivity of brass is interesting. The wiper bar I am using is brass, soldered to a brass ID tag which is spring loaded for tension. The question for me is whether I should be...

Thanks for the clarification.

That could explain a lot. Let me look at this again. Brass contains copper and it will read continuity. Is it insufficient for these small value transmissions?

I actually thought of that. I think the connections are secure. I have been over them. You can't tell from the photo, but the connections are caught between brass washers on the wire and components. The wiper bar connection is spring loaded.

It was sure bought and labeled 47k. Try this high res pic. I don't know the color bands.

Thanks, all. I did not expect such assistance.This is nothing more than a simple AM unpowered receiver unit if there was any question on it. I think the earpiece is OK. I ordered a couple of extras and the problem seems to be be present with all of them. I have checked all the connections and...

This is mysterious, and thanks for the responses. I am securely grounded to a cold water pipe. This is continuous copper, and I checked it by testing voltage to ground. I have a background in electrical work, but not in this area. I know that all my connections are secure, tested everything...

Thanks for the response. I am on the periphery of my technical expertise...trying to get my grandson interested in something other than video games. We built one of these very in very similar fashion and it worked (sort of). I'm trying to improve the design. In answer: I have attached a photo...

If anybody here has any experience with building a crystal radio, I would appreciate a response. My grandson and I are doing radio projects. This involves basic crystal build using a coil, diode, and resistor. The system is grounded and uses an antenna with no external power and a high...