This is the circuit of the commercial Japanese megaphone of the 60s model DM-218. The circuit uses a compression speaker (horn) and is powered by 4 large batteries. The output power is 2 W.
This circuit was found in a 1978 English magazine. It is a configuration that aims to select the...
This circuit was found in Maxim's documentation from the 90's. The circuit provides 12 V x 120 mA....
This circuit can be used as a shield. Its purpose is to detect the positive front of a signal...