This circuit oscillates in the fifth harmonic of the crystal frequency. The circuit is from a 90's documentation. L1 must be according to the desired frequency.
This circuit was found in a Popular Electronics from the 90s. The circuit uses general purpose...
Found in Raytheon's 1960s transistor circuit manual, this circuit employs the CK722, one of the...
This encoded lock circuit with alarm for use in homes was found in a publication from the 90s. The...