HK226 Whistle Key Finder IC

HK226  Whistle Key Finder IC
Price: $2.99
Datasheet: 

HK226 Whistle Key Finder IC.

This IC can produce a string of "Bi-Bi" sounds when it detects a whistle (approx 1KHz). Use it to locate lost items.

It also has provision for LED indications.

The App Note shows how to set it up and use it. The IC comes in a DIP-8 package.