This circuit was found in documentation from the 90s. The transistors can be general-purpose equivalents. The circuit has two versions, one that drives LEDs and another that drives a relay as a load.
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...