RC constant practical use

I've been pondering ways to 'clean up' the pulses generated by the Geiger tubes, and make them longer and more uniform. To do this I've been revisiting RC constant and their practical applications.

For the Geiger tubes, and RC circuit can form a pulse stretcher. The 1st transistor in my interface switches on the 2nd transistor, which switches the indicator LED and clicker. By adding an RC circuit between the two transistors,  I can stretch the pulses out by approximately the RC time constant. Since the tubes dead-time is 190uS, choosing an RC constant for 200uS makes a good pulse size.

The capacitor I added to cure the flickering problem was 22nF, and is probably acting as an RC pulse stretcher anyway with the 1st transistors collector resistor. 

This got me thinking of another,  really useful RC circuit.  Many years ago I used to service pendant radio alarms made by Tunstall telecom. These used a momentary push button to trigger them, and a clever RC circuit to hold the power on only long enough to complete the transmission cycle. This clearly has many interesting uses. The circuit shown is, I think, how it works.

Momentary power switch circuit, I think