So I was trying to build a crystal tester on a breadboard. Most difficult project ever so far.
There are tons of plans out there, most of them don't work.
I've never ruined so many components in one sitting, including my little home brew variable power supply. By trial and error I finally found one that works, only needs 5v and even uses standard resistor values....
**broken link removed**
I substituted 2N2222 for Q1 and Q2., and 1N4148 for D1 and D2.
I'd give the author kudos directly, but comments are disabled on his blog.