Using transistors at the time, this circuit was found in a 1967 Ferranti documentation. The circuit is for 150-ohm transmission lines.
This circuit has start and reset switches and can generate signals at long intervals determined by the...
This very low frequency circuit was found in a 1964 Electronic Design. Transistors may be modern...
Suggested by Linear Technology, this 80's circuit makes use of an operational of the time but can...