Maker Pro
Maker Pro

piezo screamer circuit

I am working on building a piezo screamer myself. I have found
multiple circuits on the web, but all of them have dozens of parts.

I disassembled one from Radio shack and found about 4 total parts.
These units have an 8 pin chip with CIR8821C written on it and a three
pin transformer to boost the piezo. How would I find out what these
part are? A web search yielded nothing.

I would like to trim my parts down and find the magic spot on the web
that sells these chips.

Any help would be appreciated..