Sentry projects in Elementary Electronics Magazine.

While cleaning out this weekend, I found a small collection of
printed circuit boards that I got from Elementary Electronics 1967-68.
They're not really worth anything, but it would be fun to know what
they are. I can't find them using Google. The dates are scratched on
the boards and the names are part of the etch.

1: Sentry Multivibrator, May 1968
2: Sentry Lo-Frequency Oscillator, March 1968
3: Sentry Hi-Lo Bander, July 1968
4: Looks like a wireless mic, no name (has 9V, ANT, SW and MIC on
the etch), Sentry, Nov 1967

These were distributed via blister pack (IRC).

Just curious.

Steve.