This circuit, of a Popular Electronics of 1969 is destined to firing a gas LASER of the time. The circuit makes use of a high voltage transformer for triggering.
Found in documentation from the 1980s, this amplifier uses an integrated circuit from the time....
The purpose of this circuit is to monitor the operation of an alternator in cars with a 12 V...
High selectivity filters can be obtained by combining same frequency crystals in series as shown...