This 4-waveband converter circuit was found in Radio Craft September 1948. The power supply is not given, but the supply voltages are indicated.
This circuit can source up to 1,000 V from a 9 V battery. Output current is very low, some...
The National Semiconductor LM675 operational amplifier can provide up to 3 A of output current. In the...
This circuit is for traditional old-style telephone lines found in an American 1980s...