We found this good amplifier in a Japanese publication of 1966. Transformers are uncommon nowadays and the power supply is included. Power is a few watts.
When the temperature rises above the value adjusted by P1 the relay triggers on. The rated voltage for the...
This oscillator for frequencies up to a few tens of kilohertz was found in a 1970s documentation. The...
This small transmitter, found in a 1982 publication, sends its signals to an FM receiver placed...