Using the 723 integrated circuit, this circuit was found in an article on power supplies in the August 1971 Radio Electronics magazine. The transistor may be the BD136 on a heatsink.
This circuit is a telephone line simulator and can be used for internal communications. It is...
This digital didactic digit counter uses common TTL integrated circuits and a common anode...
This reflectometer or standing-wave ratio meter (SWR) was found in a 1980s American documentation. The...