Building The Bat Detector

While Pica headed off to Stitches West today, I worked on my bat detector kit. It was a long haul — double-checking that the right parts were in the right place, soldering them in place, checking the soldering, clipping the leads, checking the step off in the instructions. The kit has testing instructions at various steps in the build, but the later testing steps are hard to do without a signal generator for a 40 kHz signal and ideally a scope. So I carried on. I somehow managed to do in the power indicator LED (it worked before lunch, it wasn’t working after lunch, I may have shorted it out with wire leavings underneath the circuit board), but didn’t let that stop me. The most troublesome point was when the leads to the 9 volt battery broke off the board. Cleaning out the holes in the board so I could resolder the leads was a major ordeal.

As shown above, the kit is now all wired, but not put in its case yet. Testing it (no bat required, rather it suffices to jingle some keys) revealed another problem besides the LED: the 10K thumbwheel pot for the volume control is internally loose, makes very poor contact, and probably needs replacement. I’m learning that electromechanical parts are frequent points of failure. At least all my soldering seems fine. So I’ll finish up the project once I get replacement parts.