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Why Is Tx Locked At 2 With HF Coils?


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Hey XP, why is the TX power locked at 2 for the HF coils? I am sure that you have a reason for doing so but how about clueing us in on the reason. also, why is it locked at 2 and not let us be able to change it? You could "recommend" setting it at 2 but allow us to change it as needed. The other day i was in heavy iron with the 9" round HF coil and it was just too hot at 2 TX and if I were using a LF coil in this situation i would have dropped the TX to 1 to lower the coil power as I believe that TX 2 was "reflecting" back so strongly that I couldn't get better separation even at reactivity of 3. How about changing that with the next update? 

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Gene - 

Not sure of the precise technical answer for XP omitting the adjustment on the TX power setting for the HF coils,  but I think it is because of the huge range of frequencies the coil can be run at.  Fortunately, it is not locked at 3 like running 4 khz on the LF coil or off nominal frequency.  Not even sure what TX 2 really means with respect to the HF coil.  That is what XP says it is, but without any true specs on transmission power who knows if TX 2 on an HF coil actually corresponds to TX 2 on an LF coil.  No way to tell for sure.  Perhaps it really is TX 3 and XP is calling it TX 2 to make it sound better, who knows.  On the LF coil, I mainly just set it at TX 2 and forgot about it.  One thing I am glad about is that you can adjust/shift to any frequency in the range of settings and not take a TX power "penalty", so to speak, with the HF coil.

To be frank, I never felt that TX power did all that much when it came to thick iron or even highly mineralized soil.  The reason I say this is that I have now used the Deus with the HF coil in the super hot soil of Culpeper and never missed not being able to downshift to TX 1.  In fact, I probably had my best finds ever in Culpeper using the HF coil.  That being said, the GPX still blew the Deus away (no kidding) and I have video where I set a minie ball on the surface of the soil and got a solid 80 something TID on the Deus.  Merely stepped on it with my boot so that it was covered by the dirt and it COMPLETELY disappeared off the radar screen.  Silence.   That was using multitones with discrimination at 6, I believe.  I switched to Gold Field and could pick up a repeatable audio signal but no TID.  Point being, I doubt that if I could downshift TX power to 1 it would have made a difference.  Maybe more placebo than real, except, the increased battery drain at TX 3 was indeed real.

Bottom line is that I am thankful I have one less parameter to fiddle with on the HF coil.  I think you can compensate with proper use of Disc, Sensitivity, Reactivity, and perhaps even Silencer.  In real thick iron, I use an unmasking program that consists simply of Disc set to 10, iron volume at 3 or higher, and use of pitch tones (I set the pitch tone to the highest frequency setting possible or whatever frequency is best for your hearing, the frequency that stands out when you hear it).  In iron, I hear the iron volume through the disc filter then if non-ferrous is hiding in there somewhere amongst the iron, it will scream like a banshee.  At the lower frequency on the HF coil (14 khz +/-) I might get some iron wraparound screeches, but not with the higher frequencies.  You can tweak the unmasker further by lowering sensitivity into the 80's then it acts like Gary's sifter program (but with disc and pitch).

I honestly do no think XP is going to fiddle with bringing TX power back for the HF coils.  In fact, you are one of the few folks I have seen who has actually missed it on the HF coil.  I can only suggest the tweaks to the other parameters I suggested above, with the principle one being lowering SENSITIVITY.  As always, make sure you are properly ground balanced and you may want to switch to manual GB when in thick iron.  Oh, and give ver 4.1 a shot and see if the new ground sensitivity adjustment helps.  You want to keep it low (around closer to 1 to 3) in highly mineralized ground and higher (8 to 10) in sugar sand.  6 is the Default setting and is pretty good middle ground.  I think folks have found that it has a more pronounced (and positive) affect on the LF coils and little effect on the HF coils, but it might be worth a shot.



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