Heathkit Gr 1290 Vlf Metal Detector

Heathkit groundtrack gr-1290 vlf metal detector.Heathkit groundtrack gr-1290 vlf metal detector all resistors are 1/4 watt, 5% tolerance and all capacitors are in microfarads (uf) unless marked otherwise.Voltages were taken with a 9 volt supply and a setting with no .