This circuit is from a 2004 documentation serving for signals from 1 MHz to 160 MHz. The antenna is of the telescopic type and the analog instrument is of the type found in old sound equipment.
This bargraph circuit using LM3914 was found in the October 1980 Radio Electronics magazine. Note...
This is a Philips commercial circuit from the 90s. The integrated circuit must have a good heat...
This circuit was found in a 1967s Motorola documentation. The circuit regulates the voltage of an...