This sophisticated workbench power source was found in 90s Radio Electronics. The maximum current is 15 A and the voltage can go to 37 or 42 V output.
This circuit of a 1978 American publication monitors a telephone line by triggering a relay. The...
This interesting FET-tester circuit was obtained from an old American documentation. The bipolar...
This old VHF TV booster that also serves FM was found in Radio Electronics magazine from April...