This is an amplifier circuit intended for modulating transmitters. The 5-tube circuit is from an American manual from 1947. The power supply uses a transformer.
We find this vibrato configuration with transistors in a 1987 documentation. The components are still...
This circuit was obtained in a 1967 Electronics World. The components are still common today, the...
We found this voltage regulator for 5 V with current up to 10 A in an old manual of integrated circuits....