This circuit is from a 1968 publication. Here we have several types of resistive sensors with individual adjustments triggering a single SCR. Power depends on the type of sound device to be triggered.
This limiting circuit with an operational amplifier has an adjustable cut-off point and can use...
We found this circuit in a 90s Radio Electronics. The circuit uses a transconductance operational...
This circuit provides 70 W at 8 ohms and 100 W at 4 ohms. We found this amplifier in a 1992...