Tone Oscillator (CB22066E)

Found in old documentation, this oscillator with the LM380 produces an audio tone in a speaker. Frequency is set in VR1.

Instrumentation Amplifier with Differential Input (CB4929E)
The integrated circuit used in this 80's differential amplifier is a quadruple version of the 741...
X-ray detector (CB24101E)
This circuit was published in a January 1971 issue of Radio Electronics to check television...
RIAA Stereo Preamplifier (CB11479E)
This circuit was discovered in an English publication in 1979. The circuit can still be assembled with...