[quote kneelever][quote Monte]eq2 .. Like you do, I generally prefer a locked GB with either the MXT or M6. There are times when I will use the tracking feature, but generally I prefer it 'locked.'
I did note the following from your post that I felt warrants some comment:
"I have a mxt, and have found some really nice coin's in 5-6" range."... I, too, have found good coins in that range with the MXT/M6 models, but most coins are still in the upper 4". When I get into coins that are from 4" to 6" and sometimes 7" or maybe 8", those are honestly deep coins. Question: Was that the actual depth the targets were at from the coil, or are you simply reporting the MXT's coin depth reading?
"On a 7" deep wheat penny, and 1 other that turn out to be a ih 1892. My reading change on each pass it varied so much that first pass it would read in -10 iron to the second past +20, 3rd past 35 so on up even to the 7th time going over it reading at +74. If i went over it 7 more times it would do the same readings. The targets were not in a trashy area."... Again, was it a 7" depth reading or an actual 7" recovery depth? That is a deeper coin and, depending upon the ground mineralization you were dealing with, it is not out of the norm for erratic VDI's like you had.
"Now is this normal for the mxt to have this much range on vdi numbers?"... Yes, quite possible depending upon the coil used, the depth and position of the coin, ground conditions, etc., etc. Very typical of a deeper-coin response with most detectors. TID is seldom, if ever, accurate to anything close to overall audio response depth. Some makes and models do much better.
".. or is it me not tuning the mxt right?"... Possibly. It is possible that a too-low Gain setting could impair performance, or if the locked GB setting is radically off from what would be 'functional.'
"The part disturbing me the most, my friend was using 5900 di sl had no problem's iding them plus finding 13 more wheat's that day."... Possible reasons are: using a faster-motion model maybe your friend covered more ground that you did. Or, your friend was just more fortunate that day and put his coil over the targets that you didn't. Maybe your friend is more experienced with the 5900 Di Pro SL than you are with the MXT?
Also, he's using a design that has been well proven and has an exceptionally accurate TID circuitry. Also, the 6.59 kHz operating frequency
might be a slight 'edge' in his favor, or you could say your 14.++ kHz frequency cut in on the performance over a higher-conductive coin.
And every time he was over a one it id them as a penny."... Higher-conductive coin. How did you two do on nickels and other lower-conductive targets> Also, what coil was your friend using?
"Soil in my state not to bad range from 50-65."... Good, lower mineralized ground, although there are other factors to consider, but in-the-field side-by-side comparisons over the same located targets keeps everything fair.
"I was using 6x10 dd coil with gain at 10, disc at 4 ,fresh battery's, and hum was set to where u could just start to hear it with head phones in c/j mode.I geb in a clear none metal area with Tracking on then moved to the middle postion tracking off."... Okay, that sounds pretty good. Maybe a little high on the Disc. for some, but certainly a good set-up.
But what coil and settings was your friend using? If he was using a 950 coil, he might have had a slight edge on you for depth. The 6x10 DD is an 'OK' coil, but why did you choose it (I am curious)? If your ground readings are that low, the DD coil isn't considered an advantage to help with ground handling. And I have found that, for the most part, DD coils will be less accurate on TID, especially at depth, than concentric coils on most White's models as well as some of the competition. Also, usually, a concentric coil hunts a little deeper so, it is possible, that your coil choice could be one reason you had the performance you're reporting.
"p.s after i compared reading i did find 3 wheat in 15 minute's, but they all varied the same way."... So, that suggests that 'luck' and simply putting your coil over the target is very important.
"I also change back to stock coil reading stayed the same."... Okay, and this reminded me that one feature of the MXT/M6 models is that you get a fresh TID reading on each pass, and that I have witnessed many people over-sweeping the coil or under-sweeping the coil, and that can cause errant TIDs.
The MXT/M6 are slow-motion, quick response models but need a coil sweep that's not too fast, AND directly centered over the target. Sweep the entire coil past the target before re-sweeping. Do not sweep a lot more than just across the target, and don't stop the coil before it is swept fully across the target, especially on some shallower targets.
"Funny part at another place where coins avg 5" i did very good with dd coil and out performed him in finds, but add 2 more inches in depth and he walked behind me laughing while digging up the mxt missed coins."...
"Analog vs digital? Old tech vs new tech???????"... Well, I like the MXT. I like the M6 even better because it is simple and gets the same job done. I like them for certain applications, but..
I prefer my XLT for 'cruising' for shallower coins. I prefer the White's 5900/6000 Di Pro SL's performance, or the performance and feel of the 6000 Pro XL/XL Pro for better depth and TID accuracy on deeper coins (in the over 4" range) of all the White's models. Actually, I can get better TID accuracy on deeper coins with a modified IDX Pro than my XLT or DFX or MXT or M6, but it lacks additional information.
Make sure you're not hunting at a too fast sweep speed. That's one reason I have seen some people do poorly with the MXT/M6, especially in more mineralized environments.
Remember, too, that there are some makes and models that are very accurate to their depth of detection, but they have limited overall depth. You just have to master your unit and know it's limitations. Analyze, but go after those 'iffy' TIDs and also remember that TID is discrimination. It's main purpose is to let you know a target is likely to be trash. Alerting you to it possibly being something desired is just a bonus. If the audio sounds good and the TID is good or questionable, dig. If the audio is not good and suggests a possible junk target, and the TID definitely suggests a junk target, then maybe you'll want to pass that one up.
Monte[/quote][/quote]
. I told hem get back to he's own side 
, and started to get the deeper coins now that i could understand what mxt was telling me. Yes i was dumb for not digging all deep non iron readings. At the last church targets were in 4-5" range mxt most of the time was dead on.
I do plan on using relic mode with disc at 0 and trigger forward if it don't drive me to 
. We will be in northeast part of Kentucky. Any tips from anyone with coils or modes that i should use will help allot. I do have 3x6dd, 6x10 dd , and 
!