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.
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.
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).
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.
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
Comments
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