This circuit was found in RCA documentation from the 1980s. The circuit uses LDRs of the time and the 50 uA instrument has zero in the center. R1 and R2 may have 2k2 and R3 10k typically.
Found in the October 1992 Radio Electronics magazine, this oscillator is controlled by switch S1....
This variation of configuration that is common on our site was found in a 1980s documentation. LEDs can...
This circuit was obtained from a European magazine of the 1990s. The integrated circuit used is...