Minelab GPX4500 tips, settings, questions

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Yes the new 45 runs smoother and quieter ground balances quicker over the years I have had four :Y: 4500 and the latest one is the best this question was asked a few weeks ago ,if you find it there was a reply that JP put on another forum with a review on it regards john
 
Finally bit the bullet and bought a detector. Below is what i bought.

GPX 4500.
Nugget Finder Evolution coil 17x13 inch
Nugget Finder Sadie coil 8x6 inch
Mine lab Commander Mono coil 12 inch
Mine lab GP Series DD coil 10 inch
Mine lab Pro Sonic
Garrett Pro Pin Pointer
Mine lab harness
Pick
Mine lab ear phones
Mine lab lithium battery and chord
1 x Velcro attachable lenyard
Doug Stones Gold Atlas of NSW
Original packaging
Plus the balance of 3 year warranty.
Currently 2 years 3 months left.
This machine is less than 12 months old and is exceptional value at $3500.

Pretty happy with my purchase. Should help find the allusive SA gold :)
 
great detector mate and good buy. Good luck with it and with WA. Im heading to Kal for a week in Nov and starting my research now on where to have a swing.

GT :)
 
I had the identical gear on my 4500 :Y:
The 2 nugget finder coils are both great and compliment the 2 minelab coils nicley. Should be all the spread you need.

This is the 17 X 13 on a small .2g or .3g peice i filmed in WA.
Easy to pinpoint and very sensitive
https://youtu.be/nC35YI5ZqGk

4500 is a great machine and will find the gold under the coil. Not easy in this great state though SA :goldnugget:
 
I'll cut right to the chase, out today with commander 11 mono in a place I'd usually go solely with the DD. Successfully picked up some deep lead but struggled with noise issues, regular culprits, orange domes, charcoal, and extra noisy ground (heavy ironstone and mineralisation).

In order of change what would you guys adjust? If it helps I usually detect in fixed and GB to one side but wondered if adjustments in tracking might be something else to consider. I've done it to death in DD and looking for something usable with the mono.

Cheers
 
Hi OldGT
This is one of the biggest 'how to' questions in detecting in the highly mineralised Vic GT. I've spent many hours pondering the matter, re-reading the user manual over and over again, listening to others, and trialling different settings. This is what I've come up with to date, but I'm open to anyone offering up other suggestions. I'm still learning and no expert. But think it's a great topic and I'll look forward to seeing what others think.
I perceive this matter in terms of what to do as mineralisation gets worse. What settings do you change as it gets worse?

This is what I enable in stages and in order of increasing ground mineralisation.
Reduce Rx and Sensitivity set relative to Rx, 1 under where audio response starts to chatter
Quiet Audio
Sensitive Smooth
Reduce Target Volume and Reduce Signal level
Medium Tracking or in extreme situations fast
Lift the coil 10 to 20mm off the ground
All these things are discussed in the User Manual relative to high mineralised ground.
I've played with all these in different combinations. It's good to play with a buried test nugget so you get a better sense of what the impact is.
It's a matter of adjusting these things to suit the area.
In the most extreme mineralisation I find the combination of Sensitive Smooth, Quiet Audio, Reduced Target Volume, Reduced Signal and Fast Auto Tracking all together works very well but you loose some depth. I've been told not to use them together. However for me it works amazingly well on smaller shallow targets in extreme mineralised ground which you do come across in the Vic GT. I certainly wouldn't use this combo if looking for larger deeper gold. I restrict it for shallow small gold.
I suggest you or anyone test this staged process for yourself to confirm performance in your own mind.
Good luck and let us all know how it goes.
P.S Last time out I tried Specific Ground Balance but didn't notice a discernible difference. I'd by interested to hear how you find it.
Cheers Andy
 
Thanks Andy. It was your original specific question in an old thread that I read. I've just been out to a relatively quiet area I've had success on and tried this method. Although no discernible difference I did pick up 7 targets both shallow and deep (no gold) that I had missed before even with the overhead flight interference so it may be coincidental, or may be helping.

I'll be out for the next few hours and will report any significant improvement. I'm of the opinion that more difficult ground might be worth trying to conquer to add more to the tally. Cheers
 
Probably most importantly, which timing were you in?

For mineralised ground with a mono coil, I'd want to be in "Enhance" or "Sensitive Smooth"

Just asking because as you've been running a DD, you've probably been in "Normal" timing
 
Yeah cheers mate I had tried both. In the end I just conceded to switch to quiet which ran the most stable. in this area I just have to concede and find middle ground between stability and depth/target response.

If anything I felt specific GB made it more erratic rather than less.

For most of the day I found switching to quiet, sensitive smooth, med tracking and fixed got me through most of the ground I was working without giving too much away in performance and trialing a few small adjustments here and there. Just switching to quiet was at least 70% of the change needed to make the ground workable. Got a few targets I'd missed, but as is usual I lost interest after about 4 hours (22hrs) with the last half an hour with consistent emi interference.

No luck on the gold front but work has been delayed for another day so I'm heading out fresh in the morning to try elsewhere.
 
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