back to 11m (CB) foxhunt (aka Cat and Mouse)

my CB Finder:


This was a hand-held directional receiver I cobbled together in the early 90s. I had no radio theory to work
with so I was just going on what I had, experimenting to find something that worked. I started with a Kraco
CB Super Deluxe, removing it from its case. I found a metal box to install it into, that I was going to try
to keep as shielded as possible. With the board inside, I also installed a 8 cell AA holder to power it. Now
normally that's not enough for the radio, but it wasn't going to transmit, so that should be okay.

I drilled and installed external channel, squelch, and volume controls. Then I cut a hole for the channel
display, and a bunch of holes for the internal speaker. I moved the signal meter to the outside, but ran the
wires through feed-throughs to go into the case. I put the SO-239 and a primitive attenuator circuit on the
back, and duct taped a PVC pipe to the case.

One the end of the pipe I attached another SO-239 with coax, to go to the radio. I made four different
antennas for it, with PL-259 connectors, so I could swap antennas as I got closer. The big one was pretty
sensitive, while the little one was pretty well attenuated. They were just loops, and I found that I could
change their behavior from "hunt the null" to "hunt the peak" by simply flipping them over.

It was originally designed to track down annoying people, and although I wasn't planning to confront anyone,
simply giving out a house number or vehicle description (and stripping them of their anonymity) was usually
enough to get people to stop causing trouble. But it worked very well to track down the Hidden Transmitter.



Finder 1:


Finder 2:



highest resolution images
last updated 11/15/2023 at 17:33:33