We found this timer for times of a few minutes in a 1974 Ferranti transistor manual. The relay is 37 mA sensitive type.
This circuit converts pulse frequency to current, which is indicated on an analog instrument. The...
Based on an LM317T, this circuit found in Popular Electronics works with signals of frequencies up to...
The Texas Instruments LM5178 Buck-boost controller is capable of operating in the 4.2 to 55 V (60...