This circuit makes use of a low impedance microphone. The relay is according to the supply voltage which can be between 9 and 15 V. The operational gain is approximately 100.
For a negative voltage of -48 V, this circuit from the 2005 Linear Technology manual makes use of an...
This circuit is indicated to power TTL circuits with current drains up to 500 mA. The transistor...
The number of pulses produced by this circuit depends on the switch pressed. The circuit is from...