This circuit for cars of the time was found in a Popular Electronics magazine from the 90s. The circuit is based on CMOS logic that is common even today.
This circuit is from a 1967 General Electric SCR manual. Modern equivalent SCRs can be used. The...
We found this circuit in a 1985 documentation. The 4-LED bargraph is excited by an input voltage. The...
Using the HA2400 this circuit has its output voltage digitally programmed from the references...