This TTL time base for 60 Hz or 50 Hz can be used in instrumentation circuits or even with microcontrollers, serving as a precision shield. The circuit is based on 7400 NAND ports and two transistors.
This circuit was obtained in a 1977 magazine, but it can still be easily assembled, as the...
This intercom for the 27 MHz band was found in a recent English documentation, working with a...
This relay shield circuit for old computers was found in January 1983 Radio Electronics magazine. The...