This circuit is from a Radio Electronics from March 1970. The integrated circuit used is one of the first for this purpose, being improved later leading to types that succeeded it.
To operate in a harmonic of the crystal frequency, tuned to a trimmer in the resonant circuit of...
This amplifier for recording heads was found in a Radio Electronics from September 1963. The...
This circuit is from the 1983 Intersil Databook. The circuit operates on 5 V power and has a...