This circuit uses an HA2400 consisting of 4 digitally controlled operational amplifiers. The circuit is from a Radio Electronics magazine from March 1980. The power supply must be symmetrical.
This full wave control with SCRs uses a different solution to avoid using a diode bridge: a pulse...
This circuit is from 1975 documentation. Transistors such as 2N3055 can be used and the...
This configuration based on a conventional astable multivibrator was found in a 1982 publication. The...