This circuit is from a 1980s Motorola documentation. The circuit makes use of old components that can in some cases be exchanged for modern equivalents.
This circuit uses a 7-segment display to indicate the logic level of a test circuit. The power...
This circuit provides a signal when dialing occurs. The circuit is powered by the telephone line...
This circuit is recommended by Texas Instruments in the datasheet of the TL317, equivalent to...