Obtained in a 1969 Ferranti documentation, this circuit dissipates only 2.2 mW with 4.5 V. The circuit can be designed based on modern equivalent transistors.
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...