Found in a 1964 CQ magazine this circuit consists of an automatic telegraphic key, providing the correct duration for points and dashes. The circuit can be made with a current PNP transistor.
A negative floating regulator capable of supplying an output voltage of -100 V with regulation of 20 mV for...
This negative ion generator was found in a 90s Popular Electronics. The autotransformer can be an...
The integrated circuit used in this 70's application is uncommon nowadays but knowing that it...