This counter was found in the November 19983 issue of Radio Electronics magazine. The power supply can be between 3 and 12 V typically. The counting speed depends on C1.
This circuit is a driver for R-2R network of AD converters. We found it in manufacturer...
This circuit was found in an American publication from the 60's. The transistor is made of...
This circuit produces an audio tone on the speaker or magnetic capsule. Rx must be such that added...