Simple chirp (swept frequency) generator

[alec_t]

Here's a proposed simple generator for a swept frequency square wave (as yet unbuilt).

According to LTspice it is not fussy over component values provided the time constants R1C1 and R2C2 are different.
The only uses I can presently think of for it are as a test signal generator, e.g. for determining a filter or amplifier response, or in a chirp sonar application. Any other uses you guys 'n gals can think of?

 

[Tony Stewart]

Initial conditions on Vcap also affect the response.

In this case equal RC values but mismatched Vcap 2.2 on upper and 2.5V on lower with a drop in frequency from initial oscillations

Neat effect but sensitive to voltage threshold or supply changes

 

[BobW]

Neat little circuit. I like things like this.
Can't think of any immediate uses for it though.