The 1: 1 transformer on this circuit found in a 1967 Electronics World can be wrapped around a small ferrite rod. The circuit operates with 600 to 6 000 Hz control signals.
This linear circuit was found in a 1965 Electronic Design. The transistors are from that time....
This TTL time base for 60 Hz or 50 Hz can be used in instrumentation circuits or even with...
This circuit was found in a 1980s documentation. Modern operational amplifiers can be used. The...