This instrumentation circuit was found in the September 1989 Radio Electronics magazine. The circuit uses an analog indicator and the power supply must be symmetrical.
This circuit is from an old American publication, using transistors of the time and operating with a 48...
September 2016 - It can be obtained from Mouser Electronics the new ADC AD7779 from Analog Devices with...
Found in a QST magazine from the 90s, this circuit broadcasts on different amateur radio bands...