Modulator Amplifier (V1574E)

This circuit is from a 1938 tube manual. Transformers are the critical components. Component values are given.

Limit comparator (CB9591E)
This is the traditional configuration for a limit comparator or window comparator, using two...
VCO With Potentiometer Control (CB15465E)
In the figure we show how to add a 100k ohms potentiometer to implement an oscillator controlled by this...
Monostable 4013 (CB4604E)
This circuit uses one of two D-type flip-flops available on an integrated circuit 4013. The...