WHITES GMT Goldmaster information and questions

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I've been out with my GMT about 5 or 6 times now. I've found everything but Gold. After reading this forum I tweaked my setting so I'm really confident if I'm over gold I'll get. Thanks for the tips guys!!!!
 
I have only had my GMT for a couple of weeks. Have down some extensive testing of small lead targets under ground in gold bearing grounds with the GMT. I have found by these test targets that if i can run with a gain of 5 or above with the v-sat set at six then i found this better as the machine makes a nice zip zip signal on the test pieces. Also with the v-sat set at 6 and below it gives a better feel for the ground i run in. You can recognise negative hot rocks and ground mineral patches better because negative hot rocks will make a boo boo sound and concentrated mineral patches will be a broad weak drop out in threshold. However if i get to many drop outs in threshold then i have no alternative to raise the v-sat to 7 this will remove all the drop outs but maintain some feel for the ground i am running in. Also if you get a good repeatable signal in v-sat 7 then you can turn the v-sat quickly to 6 and this will give you a better feel for the target. There has been many a time now that a positive hot rock sounds good in a high v-sat setting only to be rejected by turning the v-sat back to 6. Will be heading out to some fair dinkum gold areas soon will see how she runs then.

I forgot to mention that the ground i mainly run in is not so high mineralised but more highly variable...Roscoe
 
Keep them coming guys good stuff'
What might be something to think about also other than the best settings
Is raking! I rake everything and always have I put myself in the habit when I first started gold detecting because it's the most important. Small rocks you have to lift the coil a inch to clear them but the coil is an inch off the ground for 2 ft whilst you swing to miss one rock'
So if there is one rock every swing your off the ground an inch all the time! The GMT's
Advantage over the best detectors out there is on tiny gold that others miss but the GMT will miss it too if you don't get it nearly on the surface cos all the small stuff I find have been 1 or 2 inch deep in old surfacing areas or known gold nugget areas. Lift that coil a inch on most tiny shot pellets and there gone.
Don't forget to cover over the area aflterwards to put it back how it was found.
 
That definitely sounds like a good idea with the a rake. What about a good leaf blower to blow the small rocks, leaves, twigs etc.? I find that with the v-sat on 6 and below that the coil makes less noise when you hit a rock or stick etc, In the higher v-sat settings i can not ride the coil on the ground because of this..roscoe
 
Yes iv used a leaf blower but it makes a bit of a dusty mess and our miners right states no mechanical tools only hand tools so I just use a rake cannot get in trouble that way.
The GMT coils are very hot coils sound off on most things' sticks,twigs,rocks and hard clumps of clay turning settings down makes the most difference but will loose sensitivity to the 0.02-0.05 gram bits, raking and being careful not to hit anything works best
You can also run in manual and ajust your gound setting to minimize false noises
But will loose an edge on sesitivity aswell plus become oversensitive to mineralisation.
Raking the ground rock free also seems to stop a lot of false signals caused by hot rocks
 
I will be definitely packing a rake with me next time. If i find an area with some small bits then i will definitely use the rake. yes i agree most of the surface rocks cause most of the noises so raking an area makes even more sense. Going on sunday for a look around at some old workings, will throw the rake this time. thanks roscoe
 
I have the stock 10 dd coil that came with the GMT. This seems to be a good coil, however it a strange one. Does any one feel that this coil is more sensitive towards the front of centre? I was just wondering how the 6" shooter coil runs and wear is its sweet spot so to speak, thanks...roscoe
 
Hey Roscoe
I'd have to agree that the STD 10" seems more sensitive
On the centre front half.
The 6" shooter stays on most of the time, I have two and the two of them both handle mineralisation betta than the STD 10" The entire centre of the shooter coil is sensitive.
I also have the 14" gold max and even tho it's heavy still very sensitive I found a .1 gram
50mm deep! Air tests a ounce piece at 1 foot!
 
Thanks for that zuke, i think i might gets me self one of those shooter coils. Would be real handy around rocks etc. If it runs better in high mineral soils than that,s a bonus. I don't do air tests much zuke, i always bury my targets for tests in mineralised soils. It would pay any way to have a back up coil. Its good to know that this coil has a more even sweet spot too,thanks roscoe
 
Thanks for that backcreek that was a good read. I really do need a back up coil for the gmt and with this coil it should come close to the gold bug 2 for sensitivity to small bits.
 
Hey guys,

I am still having trouble and not sure I am doing this detecting thing right, I am pretty keen to learn from someone who has a GMT and if someone would be keen to take me out and show me the ropes I would be greatful. I just can't seem to tell what I am looking for, I find myself digging holes and find the signal goes away does anyone else get this? I check the piles and nothing fill the hole and move on. Needless to say I am getting a little frustrated and find myself more and more just going to the dark side and simply go panning or highbanking. I am keen to learn and even have a detecting partner that runs a GMT.

I have watched the videos and everything. The only way this machine seems to work for me is with the black sand meter on it to find places for highbanking. I am having issues with identifying the correct targets to dig.
 
Newbie said:
Hey guys,

I am still having trouble and not sure I am doing this detecting thing right, I am pretty keen to learn from someone who has a GMT and if someone would be keen to take me out and show me the ropes I would be greatful. I just can't seem to tell what I am looking for, I find myself digging holes and find the signal goes away does anyone else get this? I check the piles and nothing fill the hole and move on. Needless to say I am getting a little frustrated and find myself more and more just going to the dark side and simply go panning or highbanking. I am keen to learn and even have a detecting partner that runs a GMT.

I have watched the videos and everything. The only way this machine seems to work for me is with the black sand meter on it to find places for highbanking. I am having issues with identifying the correct targets to dig.
hey Newbie i run a GMT mate, they can be a bit stressful at times as they are so sensitive however you need to persevere time is he only thing that will teach you. Go to an area that has lots of lead bullets etc and spend a day digging trash its the best way to learn. I personally take with me a piece of lead and a very small piece of gold maybe .03 picker. when you setup in an area find a piece of ground with minimal sound and throw your lead down. now tune your detector to the response, everyone is different you can make it a long wining response or a short sharp one which i prefer. Gold sounds very similar to lead so its your best friend in the field.

Sometimes you are digging ground noise when you hit orange/yellow chalky clay and you can often test this by simply busting the ground up and waving again the signal should increase not decrease if it does decrease its likely ground noise. however sometimes you will have a flake of gold so small it sounds off in the ground but makes very little variation when waved over the coil after digging.

Try placing your GMT on the ground with ground balance flicked to manual and audio signal boost on, now wave your hand over the coil and find the height that does not give a response, then do the same with your plastic cup/scoop once you know this height you should be able to determine when and if there was a signal in your hole.

I have one final trick but its a personal preference for me and might not work for you, I went down to dick smiths and got a $5 dicks brand set of low impedance headphones, I then removed the earth contact for the headphone jack which pulls the signal back to mono. I find this much less chaty and very easy to focus in on small signals. hope this helps
1383524738_20131104_112107.jpg


sorry just realized how crappy that picture was, this is the earth connection on your GMT it screws out quite easily
1383526111_20131104_114619.jpg
 
Newbie - I dont run a GMT but it sounds like you are digging ground noise. This is an age old problem - signal sounds OK and then when you dig down it either moves, is gone or is till there but the same sound and sound level. These are pockets of mineralised soils, hot rocks, and the like. When you hear a suspect noise, and ground noise can be a broad one-way signal, cross it at angles (pin-pointing) to see if the sound brightens up or is the same. Dig a round (no sharp edges) hole a little bigger than the coil and re-check but dont put the coil in the hole. If it has moved, generally to one side, or gone its probably ground noise. Do you have lead practice targets? Try these to get the sound you should be looking for. Bigger gold that is deep can give the same very faint signals so if you are just starting, its worth while digging these just to be sure. Make sure when you sweep the coil is at a constant level - a problem can be a thing called coil lift where the coil is raising at the end of a sweep - this can also give a false signal at times. My advice is to have a close look at what you have dug out - this way you will learn what is causing the problem. Most of the time you can see hot rocks on the surface and eventually you will discount these as well - they all look the same - nasty reddish flattish rocks that can give a very nice faint signal. Pick them up and break them up and re-detect each piece. You will find the offender very quickly or you may have even pinged a little specie as some hotrocks are ironstone and they can have gold in or on them.

Hopefully a GMT user will give you some more detail.
 
Hey Newbie where bouts do you live?
If your not too far away ill take you out and show you the goods
You can try some different coils too .
I'm in mooroopna near shepparton vic
 
Newbie, would you be able to let me know what settings you were running on the day?
 
Hey Zuke what your base setting for the GMT .
I'm using Ground balance fast.
Audio Off
Iron I.D> Center
S.A.T 6
Gain 6 - 7.5
Threshold very low
Zakman
 
Yeah mate your setting would be very close to what I start with I nearly always use fast it works well and iv found 0.02 nuggets that it didn't tune out.
If you rake the ground over first you might get away with more gain
I use the threshold as a volume I just turn it up it doesn't worry me but when I turn the detector off for lunch I can still hear it.
The wife thinks I'm mad listening to all the crackle and pops from hot rock and such but there's only one noise that grabs my attention! Practice with a lead shot pellet.
 
Thanks Zuke.

Yes i have test samples set up one is a lead shot.
Good Hunting.

Zakman
 
Zuke, would you explain please in a bit more detail about you using the threshold as a volume control, that sounds interesting. thanks roscoe
 

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