This circuit was taken from an old American documentation. It can be built with modern op amps. The power supply does not have to be symmetrical.
Published in 1988 in Hands-On Electronics, this circuit converts the 12 V of a battery into 120 V...
This 10 mA microammeter circuit can measure currents of 50 uA. The circuit is from a publication from the...
This receiver was found in an article in Electronics Now magazine in March 1994. The coils are...