I’ve been keeping my eye out for a mic for the hw-101 for since I got it. I’ve been partial to the Astatic D-104’s, but the prices for them have been too high for my taste. I recently found one on ebay that seemed to be in good condition for a reasonable buy it now price, so I picked it up.
The listing didn’t outright say that the mic worked, but I was under the assumption that it did. After messing around with it for about an hour and swapping plugs several times to try on different radios, I cracked open the mic element. It turns out that crystal was completely disintegrated.
I replaced the crystal element with an electret and soldered in a 1k resistor between the mic line and the 9 volt battery in the base. I stuffed some foam around the electret and closed up the head. In my haste, I didn’t get any pictures of the electret/foam, but to be honest there wasn’t much to it. There are probably tons of other guides online.
I didn’t have a 2 pin mic connector for the hw-101, so I had to settle for testing the mic on an old cb radio. Everything seems to work okay. Once the connectors come in, I’ll try it out on the hw-101 and get some audio reports.