This is a typical point scale or moving bar circuit with the LM3915. We found it in old American documentation. The operational amplifier supports an equivalent modern type.
This circuit can be enabled and disabled by a TTL signal. The relay is a low current reed type and...
This circuit was found in a 1965 US documentation. The circuit converts a DC signal to a 400 Hz AC...
This circuit can function as a high-power shield completely isolated from the power grid. We found...