100 kHz Oscillator (CB22379E)

This is the single-sourced version of the previous oscillator. Frequency can be changed by changing C1.

LM3914 Moving Point Voltmeter (CB25113E)
This circuit was found in a March 1988 Radio Electronics. The voltage scale is set at R3. 19 LEDs...
Audio Booster (CB23695E)
The idea of this circuit found in a Radio Electronics from January 1966. The idea of the...
Audio Visual Thermometer (CB18469E)
This circuit was found in a 1974 publication. It provides a tone indication of the temperature sensed by...