This circuit was obtained in a Electronics World of 1968. The transistors can be equivalent as the BC558 for the PNP and the BD135 for the NPN powering lamps from 3 to 12 V according to the supply.
This field strength meter is intended for the VHF range, above 100MHz. The lowest voltage or...
We found this circuit in an English publication in 1976. The circuit is based on the use of a...
This antenna tuner was found in a 1995 publication in the 1993 Electronics Hobbyists Handbook. The coil...