Building the Widlar Hassler

One of my personal favorite Bob Widlar pranks was his “hassler” circuit, which he used to combat office noise.

If you spoke too loudly in the presence of the hassler, it would emit a high pitch tone, which would decrease in frequency the louder you spoke; this had the effect of causing an annoying ringing noise in your ears. As soon as you noticed the ringing and stopped talking in order to identify the source, the hassler would shut up too.

The Widlar salute!

The Widlar salute!

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