RF and Audio Probe (CB5912E)

Any FET can be used on this 80's circuit. Power can be supplied with batteries. The output is applied to the input of a small audio amplifier.

Electronic Micro Organ (CB4440E)
This circuit, which uses only common transistors, was obtained from a 1988 publication, but can be...
Pink Noise Generator (CB5433E)
This circuit was found in a 1980s documentation. Modern general purpose transistors can be used....
Linear VCO (CB1527E )
We found this circuit in a publication for radio amateurs of 1976. The operational amplifier is a...