WHITES GMT Goldmaster information and questions

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Only recently moving to detecting, l have started with a couple of VLF detectors. When using the headphones, the emitted noise is completely different to that given by the external speakers. Is this normal and l have to learn to read the different noises between external and headphones?
Although no gold nuggets to date, l have found targets from both modes.
 
Hi RobinW,
The more you detect the easier it gets, I spent a day with Gold Prospecting Australia up at Bendigo and found it worth while when learning to use a detector , even though they use Minelab equipment they spent half the day with my whites TDI
 
6-GAIN SETTING
The highest gain settings will get the greatest depth. By dropping back gain will settle the machine down especially over hot mineralised soil but in return target depth will decrease substantially.
i generally hunt with gain flat out but run high SAT settings to compensate for the high mineralised soil.
when running high gain and fast SAT settings i always use ground balance set in fast auto trac.
I suggest a few quick depth tests changing gain from high then testing by dropping back to 3/4 gain will just show how important it is to tune the machine using the highest gain possible.
 
4- V-SAT SETTING
One thing i have found with my GMT is you need to run much faster SAT speeds than the triangle marking at 3.5x, it needs to be more like 6x or faster.
if I'm using it in most places in VIC it would be no lower than 7x with gain set at its triangle mark or higher.
There is one gold field iv hunted many times that had very moderate mineralisation and i was able to run gain at max and SAT speed as slow as 5x, iv found lots of tiny gold in this field as small as 0.01 gram.
unfortunately in australia fast SAT speed is very important on these 48khz machines, The only downfall iv found is target signal running fast SAT speeds isn't as sharp or a bit distorted unlike slower SAT speeds.
 
3-THRESHOLD ADJUSTMENT
Threshold adjustment i think is personal preference iv found small gold with it loud and quiet most of the tiny gold iv found has been with it adjusted loud so i could hear the repetitive signal response as i use the built in speaker, a quiet threshold with a added booster speaker would complement the GMT well.
Roscoe has put together a small booster speaker he might add into 8-MODS we might even get a pic out of him.
 
The courses are well worth your while doing. I did one with Gold and Relics at Clunes and Darren was excellent. He set up my machine to his settings and I was finally able to find some yella. They wouldnt be too far from you RobinW.
 
Hey guys
Whats the importance of using the correct sort of batteries? Will standard el'cheapo aa's still do the job?
 
Yes they will mate but if youve read the manual whites say change yoir batteries at 50% so you will go throught alot of dough. Better off spending $50 on soke lithium recharges mate
 
No they won't - you'll get spurious noises & other issues. Use as a minimum good quality alkaline batteries. I always used Duracell alkalines & got around the claimed 30-40hrs detecting time before they reached the 50% mark.
Lithium rechargeables might be ok but others will give similar poor results as poor quality or less than alkaline batteries.
Reasons:
Normal battery (heavy duty, general purpose etc.) 1.2v max output
Alkaline battery 1.5v max. output. Because the voltage of an alkaline battery drops at a very predictable rate: 1.5 volts - fully charged, 1.25 volts - 50% charged, 1.0 volts - at the end of its lifecycle. This is why you discard @ 50%. Still around 1.25v or slightly higher than the cheaper types even after nominal 30-40hrs detecting.
Rechargeable batteries are usually all 1.2v max. output
Lithium rechargeable batteries 1.5v max. output.

Basically with anything less than alkaline batteries you are starting off flat.
With 8 x alkalines you start at 12v & finish around 10v @ 50%
Cheapos you start at 9.6v
 
Iv always used energizers and do a few hunts put them back in the box and use them round the house' all new Batteries go though the GMT first in my house!
 
Zuke_Lynzy said:
Iv always used energizers and do a few hunts put them back in the box and use them round the house' all new Batteries go though the GMT first in my house!
Good to see you have your priorities in order :lol:
 
I can't speak for the whites, many members here will be much more help than i can be, however id prefer headphones everytime. Personally on a vlf id stick to one set of tones to decipher, i like them chatting directly in my ear for the threshold waver, i can't imagine what that would be like out in the open especially in a busy area or a windy day. I even isolate to one side of my hearing.
 
Camera batteries are best and hold current well but pricey iv always wanted to try the whites rechargeable pack has anyone ?
 
Thanks for the responses guys. The fact that the el cheapo ones from golo wont be as good is actually quite comforting.
Last time I was out I used the cheap ones and I found it wasnt picking up the test piece as well as it should have.
I still managed to find the odd small lead pellet but put the problem with the test piece down to bad ground.
I changed to the cheap batteries while I was out and being as im a bit slow its been a month for me to click as what the problem could have been :8
 

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