We found this circuit in a 1980s Motorola documentation. The circuit makes use of common operating and the voltage depends on the used type. The components are for a frequency of 500 Hz.
This system makes use of incandescent lamps only and uses a SCR with a full wave bridge for powers...
Based on the well-known LM3914, this circuit was found in an old American documentation. Trimpots...
The transistors in this circuit from an English publication in 1980 may be the BC548. Operational...