Electrical Interference

First Texas Products & Fisher Labs August 2009

Dave Johnson, Chief Designer @ FTP & Fisher

Because of the high sensitivity of modern metal detectors coupled with the proliferation of sources of electromagnetic interference, you are likely to encounter electrical interference at times during the use of your metal detector. It is important that you recognize electrical interference when present, and take appropriate measures to deal with it. This will prevent you from giving up on a worthwhile site unnecessarily, or from sending in for a repair a machine which is working properly.

Symptoms of electrical interference

Electrical interference can cause a metal detector to “chatter” spontaneously, to lose sensitivity for no apparent reason, or to cause periodic audio “wobble” or slow waves of spontaneous sound. What you’ll hear will depend on what model of metal detector you’re using, what operating mode you’re using it in, how you have the adjustments set, and what the source of the electrical interference is. The most common manifestation is spontaneous chatter.

All metal detectors are susceptible to electrical interference, but they vary in what kinds of electrical interference affect them. In a given environment some metal detectors may be affected by electrical interference whereas others may not.

Two metal detectors of the same model in the same environment may be affected differently, because of minor differences in operating frequency or because the controls have been adjusted differently.

Common sources of electrical interference

Common sources of electrical interference include: overhead electric power lines, underground power lines, other metal detectors, telephone lines carrying electronic data, computer systems, electric fences, old CRT-based televisions, cell phones, thunderstorms, fluorescent lights, metal vapor lamps, military aircraft with electronic warfare countermeasures turned on, electric motors, VLF military communications systems, and automobile ignition systems. It will sometimes be the case at home, in the showroom, or in an urban environment that there are several different sources of electrical interference present simultaneously.

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This time I take apart the Display/control pod! In the first part of this series, I “deconstructed” the under-arm housing. LINK HERE. Upon removing the screws on the control pod, I am very impressed by the use of a nice heavy rubber bushing/seal. So far, all parts appear to be very high quality on the Spectra V3. Each half of the display seat into a recessed groove…nice and water tight! There’s also a beefy rubber grommet/seal where the pod back connects to the back of the handle…once again helping keep the elements at bay….

READ MORE BELOW!  More Pics…

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Here are a few views of the interior of the new White’s Vision /V3  (there’s some kinda name issue with Vision from what I’ve picked up…so it may be known as the Spectra V3 in the future)  All the components and solders look very high quality!  For your viewing pleasure…. (yes…I imagine this would void your warranty!)  Full review of the Spectra V3 coming soon!

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*Reprinted by permission of First Texas*

Posted originally on American Relic Hunters Official Teknetics Forum

Hello! and, Omega

Posted By: dave johnson
Date: Friday, 13 February 2009, at 1:10 p.m.

Hello, this is my first forum post on this website. Some of y’all I recognize from other venues.

Since the Teknetics Omega is in the process of being released to production, there will be a lot of curiosity about it. Most of the questions will relate to features and performance in the field. There’s no need for me to go into those matters, since other people will quickly fill in the details. What follows here is a bit of information which is probably better coming direct from engineering department.

Once the Omega gets into people’s hands, it’ll become obvious that there is some sort of relationship between the Tek Omega, and several earlier Fisher and Bounty Hunter products. Here’s what that relationship is.

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