White’s Electronics GMZ User Manual

White’s gmz gold prospecting detector

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The gold nuggets shown above were found by White’s Engineer, Dan Geyer, who designed the GMZ as a simple to operate, reasonably
priced, gold detector. The gold nuggets were all found on a recent vacation trip to the mountain area west of Winnemucca, in Northern
Nevada. That is a US Dime in the middle of the picture for size comparison. The gold is mostly in 3, 4, 5, & 6 grain pieces with a few larger

The GMZ is a lightweight instrument that operates at a frequency of 50 kHz and uses all of White’s standard
Goldmaster search coils. The GMZ has only 3 controls and features all metal, silent search operation with a
unique ground rejection system.

The Sensitivity control knob turns the instrument power on or off and adjusts Gain. The Ground Reject
control knob adjusts the ground rejection range. The Ground toggle selects either Normal or Salt operating

The GMZ features an improved ground rejection system that significantly reduces ground interference and
false target responses. The rejection range increases as the Ground Reject control is turned clockwise. Low
mineralized ground requires a narrow range for good rejection. Other soils loaded with black sand or
“hotrocks” require a wider range.

The GMZ gives the prospector continuous control for the ground rejection range required for maximum
sensitivity to gold nuggets. The Salt position provides the ability to search in desert regions with the heavy
concentrations of conductive salt or alkali in the ground. The GMZ operates with the same 12 Volt 8 AA
battery pack as White’s GMT Goldmaster and gets similar battery life, which usually exceeds 50 hrs. of
operation. Simple operation instructions on next page.

For any additional questions contact White’s Electronics at 1-800-547-6911 or


GMZ Gold Prospecting Detector Information