We found this circuit in the February 1989 issue of Radio Electronics magazine. The selectors are BCD programming switches. The circuit is CMOS.
Originally recommended to give a tone of transmission in equipment of the 60s (tubed) this circuit is...
A high level on the input of this circuit causes the trim voltage adjusted output voltage to drop to 1.2...
I found this simple circuit from an English magazine from 1984. The circuit can be easily...