True RMS Voltmeter (CB25353E)

This circuit is from a Radio Electronics magazine from August 1990. The indicator module is of a common type at the time.

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Wien Bridge from 1 to 15 kHz (CB8034E)
Found in a Philips publication from the 1970s, this circuit uses a DO040, which is difficult to obtain...
Light On Car Alarm (CB1421E)
This circuit was found in a 1978 American publication. It beeps if the car's lights are on and the...
Guitar Tremolo (CB6709E)
This circuit is from an Electronics World of 1964. The circuit can be made with modern...