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E-TRAC - Two Tone Ferrous... Unlocking the "mystery" - Part 1

February 25, 2011 04:31pm

Randy Horton
Randy Digger Horton

While browsing several metal detecting forums, I've noticed numerous posts regarding the use of two-tone Ferrous (TTF) and how it has seemingly "increased the results" for many E-TRAC metal detector users. I won't disagree that they may be finding more than before. However, I believe the reason for their new found success is due to more than simply their choice of audio tones.

Regardless of whether you operate your E-TRAC in conductive tones or ferrous tones, each target detected will provide both a ferrous visual Target  ID (TID) and a conductive visual TID. By setting your E-TRAC to ferrous tones, you have chosen to hear the audio response of a given target's ferrous properties. If you set your E-TRAC to conductive tones, you have chosen to monitor the audio response of that target's non-ferrous (conductive) properties. Regardless of whether you choose to listen to the audio response of the ferrous properties or the conductive properties, the TID values will remain consistent. The audio response will be based simply on which properties you have chosen to monitor.


E-TRAC metal detectors coin discrimination program

Many of those now using TTF indicate they “migrated from” a modified Coin Program using conductive tones. When using any discrimination, such as found in the Coin Program, targets whose conductive properties have been set to "reject" will cause your E-TRAC to null out when the coil passes over them. This is commonly referred to as target blanking. Conversely, when monitoring the conductive tones, targets with conductive properties set to be "accepted" provide an audio tone whose pitch is based on the conductivity number associated with the target. The overwhelming number of those posting about their change to TTF also indicate that they "open up the screen", providing little or no rejection. 


E-TRAC metal detectors open discrimination screen

In my opinion, it is the lack of target discrimination (combined with a slower sweep speed) that has improved their results. Not simply switching from conductive tones to ferrous tones. A target with a TID of 12-44 in two-tone Ferrous mode will provide a high tone represented by the ferrous Digital Screen TID of 12 (high tone is applied to all ferrous numbers 17 and smaller).

E-TRAC twotone ferrous screen

By switching to conductive tones, with all other settings the same, I would have heard a high tone representing the conductive Digital Screen TID of 44.

E-TRAC metal detectors two tone conductive screen

The target didn't change. Nor did the TID values of either the ferrous properties or conductive properties. The only thing changed was hearing the audio response representing the ferrous value instead of the audio response representing the conductive value.

In part 2 I’ll talk about why I use TTF.

HH Randy


ok great I started with TTF early dec 2011
today march /2nd/2012/ Im at 45 Rings
its simple I have 2 tones low tone "RED" stop/dont dig//the higher tone "Green" go dig
and I dig most everything small number are mostly slaw but can be earrings ect.
I try large coil first and return with small coil and seperate signals .I.E. when in a bed of nails /all metal screen// some of the good tones can yeild good finds. gets a bit tricky. I run manual and Hot .tend to have gain volume way up and adjust the sensitivity to keep things managable.responce on smooth/ chn 2,3,4, pp sizeing/& I have a few mix and match adjustment I try /do a lot of digging, move around a lot& and research sites on google earth and make routes that I program into my auto GPS
let your coil tell u if the site is good
best finds mimic trash
trust yur gut and the machine
And I got the gold Pa
Posted By: GoldTrekker on March 03, 2012 07:17pm
Never owned a metal detector before and was wondering would a E-TRAC be too much to start with? Have just built a cabin on a small island that was settled in the early 1800 and everyone was moved out by the government in the mid 1960's. There are lots of old home sites and I would love to be able to find some of the old relics and history of the place. Lots of old iron in the ground. There about 80 cabin there now and I think a great place to detect!
Posted By: don3402 on March 06, 2012 11:19am
Don, the beauty of the E-TRAC is that it can be operated quite effectively by using the factory default settings. Then, as you become more familiar with the functionality, you can fine-tune it to suit your hunting style and your specific sites. The E-TRAC's unique ability to recognize and identify both ferrous and non-ferrous target properties will allow you to separate one target from another quite readily. And by having the ability to determine those target properties before you dig...... well, that old iron shouldn't be a problem. It certainly does sound like a great place to discover history. Best of luck and enjoy the hunt! Randy
Posted By: Digger on March 06, 2012 04:06pm
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