Darlington Oscillator (CB21142E)

Indicated by Popular Electronics, in an edition of the 90's, this circuit seems doubtful because of the inductance used, which must be large.

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Electronic Thermometer (CB21356E)
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Step variable power supply (CB8893E)
Found in Popular Electronics from the 90s, this 1.5 A power supply can supply voltages selected by a...
Photoelectric alarm with LDR (CB23799E)
This circuit was found in Radio Electronics magazine from February 1962. The sensor is an LDR, and the...