This two-channel bargraph meter uses a single KAA2281 integrated circuit. Found in the January 1991 issue of Radio Electronics magazine. The stereo circuit drives 2 scales of 5 LEDs.
This circuit can measure frequencies up to just over 1 MHz and uses CMOS technology. The circuit is...
This variable oscillator was found in a Mullard transistors manual from 1960. The resistor R5 is...
This circuit, from a 1988 documentation, consists of an automatic temperature control using an NTC...