This circuit is from an Electronics World of 1967. The described calculations can be applied to equivalent circuits with modern transistors.
This circuit, which can also be used with flashing LEDs as long as they have in parallel a charge...
September 2017 - Digi International's SX 868 RF modules for low-power 868 MHz CE / RED operation...
The signals from this circuit obtained from the 1965 Radio Shack documentation are picked up from...