This FM receiver tuning step circuit was found in a 1960 documentation. No information about the coils is given, but the FI used at the time was 10.8 MHz.
This circuit is from 1970 documentation. The SCRs are types of the era that can be replaced with 106...
The circuit shown here produces a pure square tone of 440 Hz that is suitable for musical...
This circuit has a duty cycle of 50%. We found it in old English documentation. The center...