Using a varactor or varicap, this 1969 Electronics World circuit has a modulation range from 75 kHz to 52 MHz. Modern equivalent components can be used.
This circuit was found in 90s Radio Electronics. The transistor can be any general purpose....
The circuit below shows how to obtain a monostable from a CMOS 4013 flip-flop. The actuation time...
This circuit is from Philips' 60s documentation. The circuit can be applied to modern operational...