This circuit was found in a 80’s American documentation. The adjustment trimpot is from 47k to 100k. The diodes are general-purpose types use and the supply voltage depends on the relay.
This circuit is from the 1974 Motorola Unijunction Trigger Circuits for Gated Thyristor. The triac...
Found in old American documentation, this circuit can divide the frequency of a signal by 2 or 3...
This transceiver is also low power, but this time, it can generate signals in the 144 MHz band. In the...