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.
The basic application of a 4017 as a sequencer [10 steps] is shown here. In this same part, you...
The circuit presented uses an integrated circuit Sanyo, not very common in our day. This amplifier provides...
This circuit is from a 1977 publication for radio amateurs presenting a crowbar protection. The...