Secret Circuits' Initial Contents

I used to have a geocache called Secret Circuits. (You can view the link if you have a geocaching.com user id). This cache had a bunch of old circuit boards in it. The idea was to try and guess the function of the boards when you visited the cache. Some folks enjoyed it and even added their own circuits to stump me. Some just realized I was wierd.

 

I lost the original high resolution image. Bummer!

 

Any guesses?

Done