Minelab GPX4500 tips, settings, questions

Hi All ,
sorry about all the questions,
about a month ago i purchased a second hand 4500 and have 3 coils.
I have the two 11' Mono & DD however the Commander 15x12 is the one I intend on using the most.
My questions are reading over the manual last night ,
It states in its tips on page 67 that if you put the coil/RX into cancel then you maybe able run your RX higher.
has anyone done that?

also , when on a target should I switch to normal apposed to enhanced?
anyone run theirs on Normal in the Vic GT?

SO far upgrading from a Minelab monster to the 4500 has given me the ability to dig bullets at a deeper depth....lol
I dug a bullet out the other day that would have been 6-8" deep.
https://www

minelab.com/__files/f/3965/4901-0063-1.1%20Instruction%20Manual%20GPX-4500_screen.pdf

Cheers Rob.

Hi RobbieMVFC, my suggestion would be using the 4500 in enhanced in highly mineralised ground in the GT.
But also watch a few of Minelab golds videos.

https://www.youtube.com/channel/UCv5oE31Me0MK-p7tkhRhjMw

Minelab has some great tips and tricks.
I have also included a template for you to use and maybe take down some of Minelabs settings to help.
https://www.prospectingaustralia.com/forum/doc/member-docs/8833/1524016900_4500-template_usersettings.pdf

These will put you on the right track.
But my biggest suggestion would be practice and more practice. There is gold out there but you have to walk over it. And that requires research, so maybe a visit to Dunolly Coiltek will help. He has maps, local knowledge and lessons to help.

And yes you will dig bigger holes but that is where the gold maybe. We all dig loads of lead, horse shoes etc. but all good.

Maybe also join one of the catchups in GT for loads of help from the good people on this forum.

Cheers

G'day fellas,
My names Jay, fairly new to the prospecting scene and after some very needed advice.

Just moved out to Paraburdoo, WA. Hoping to find some nuggets on my off time.
I cant seem to get more than two or three inches of detection depth on my .5g test nugget. No matter what settings I try, it seems that's all my 4500 has in her.

Tested using a 14" mono and 9" mono.
I'm sure I've tuned and ground balanced correctly, detector has no problem picking up scrap iron.

Am I making a rookie mistake? I have tried in general stock mode, deep mode and fiddled around with some settings trying to improve detection distance, no luck.
I have a sheet from a local on which settings to use which I will list below,

Any tips would be greatly appreciated!

-Jay.

Current setting recommended by local.

Coil Setting = Mono
GB = Fixed
Soil Timing = Enhance
Search Mode = Deep

Back light = Off
Volume limit = 15 (Headphones)
GB Type = General
Motion = Slow
RX Gain = 12-13
Audio = Normal
Audio Tone = 40
Stabiliser = 11
Signal Peak = 19
Target Volume = 10
Response = Normal
Tracking = Slow
Iron Reject = Off

Very low EMI, but high mineral ground where I am testing my sample.

*Coiltek coils used

hmmmm strange as to why its only going down so far. My first question I have is it a genuine Minelab and not some fake copy? I am sure some people will be able to help you with this one.

Hi Jay, I have used Minelab golds setting.

Loads of videos https://www.youtube.com/channel/UCv5oE31Me0MK-p7tkhRhjMw/videos

.5 gm nugget should scream.
My advice reset back to factory setting and try that. Then test using enhanced.

The 14" coiltek elite should detect deep.
Attached is the template you can use to test.

Cheershttps://www.prospectingaustralia.com/forum/doc/member-docs/8833/1524466105_4500-template_usersettings.pdf

Cheers

What is your test piece like..... flat, irregular, solid, prickly, it can make a big difference to how solid a response you will get and how deep you will pick it up.

Hi Jay,

Never really used a 4500 before, mostly just the 5000, but if everything is right with the machine and coils then for sure the mineralisation will be your biggest influence on depth.

I've run in highly mineralised areas where even the mighty GPZ struggles on half gram bits at eight to ten inches so I suspect that could be the most likely culprit at this stage (with the current info).

Get yourself into some milder country and you'll see an amazing difference, particularly with the 14' coil. It should have no issues pulling half gram to gram plus bits around the foot deep mark and beyond. :Y:

All the best,
Shauno.

EDIT: Sniped by OzzieAU above in regards to the shape of the nugget so I removed the info, but that's just as important as the ground mineralisation. :Y:

Try special - sensitive extra instead of enhance ....works a treat on my 4500 :Y: :Y: and back off your rx gain

Cheers for the quick responses fellas! Much appreciated!

I am 100% sure my detector and coils are genuine.

As for my test nugget, its quite smooth and rounded. Seems like a solid specimen for testing.

I have also tested my detector by bringing it up off the ground and pointing skywards, waving my test piece across it, which i expect would eliminated the ground mineralisation being a factor. Unfortunately I'd have to drive 400km in any direction to find some milder ground.

Have just done a factory reset with still no luck.

I'm bloody stumped!

Could be that something has gone faulty inside the detector. I hope that is not the case for you. Have you contacted Minelab Australia at all and explained the problem to them? They would defiantly be able to help you out.

Jay ,those settings are very good and will work well..Most coils have a sweet spot near the tip and need that on and off little swing ..I run the target vol flat out with a remote speaker and run the Stability at 6..But your settings will work fine..The other think I recon when the ground gets very hot on the surface small gold goes quiet..So it can depend on the day and the shape..

Can you test on another target, say a small lead sinker or bullet that weighs roughly the same as your test piece to see if the shape and texture are the issue?

RobbieMVFC said:

Hi All ,
sorry about all the questions,
about a month ago i purchased a second hand 4500 and have 3 coils.
I have the two 11' Mono & DD however the Commander 15x12 is the one I intend on using the most.
My questions are reading over the manual last night ,
It states in its tips on page 67 that if you put the coil/RX into cancel then you maybe able run your RX higher.
has anyone done that?

also, when on a target should I switch to normal apposed to enhanced?
anyone run theirs on Normal in the Vic GT?

Cheers Rob.

Click to expand...

Hi Rob,

With a mono coil, if in the cancel position you will lose about 95% of your depth. Can be useful to pin-point a horseshoe or a tin can.
Cancel really is intended for use with a DD coil. You lose maybe 20-30% depth, but gain a lot of stability. Hence, yes you can often increase Gain, turn up the Stabilizer, run a faster Motion setting etc etc. all of which gets a little performance back.

You generally wouldn't switch timings when checking targets as it can become confusing with ground signals. On any iffy ones, just re-balance on the side of the target and it should sharpen up a little. If no change, scrape the ground a bit and re-check. If still not sure, dig a couple of inches off. That will then tell the story. Yep, as HH states, with a mono coil in the GT, you'd usually be in Enhanced.
You can use Normal with big DD coils in most areas.

Nenad

Reg Wilson said:

Good luck with that tigers rule. Qeens gully would have to be one of the most flogged gullies in Victoria. Still, you never know, there is probably a bit left there somewhere. It was pretty good forty years ago.

Click to expand...

Yep flogged, but where isn't it these days. Still, that's one spot I never fail to find gold. Got 5 bits there once with the 5000 and 11" Commander, and left plenty of targets in the ground due to an incoming storm.

Hi guys,

Last year on my training day I explained to the instructor that I had access to a mates block at Korong Vale and being that had a tiny creek running through that lead onto a gully that was worked about 100 meters away behind the old reservoir it could be worth checking out. The issue was that there's a heap of bullets on or near the surface as my friend and his mates have been shooting on the block for years.
The instructor said he could show me how to set the detector to run deep and ignore the shallow bullets, sounds perfect but we ran out of time being it was a large group on the training day.

I've googled on the subject without luck and only come up with settings for depth which is not far off what I use now but still pick up tiny surface targets as well.

Is there actually a way to ignore surface targets? Is it done by the target signal (inverted) or the strength of the signal? I get that the surface bullets will scream (as I've already done an hour here last year for 20+ .22 bullets) but a large nugget at depth could also potentially scream.
Any advice or help appreciated as I'd like to do a weekend up at his block soon and if I can ignore the surface bullets and focus on deep targets it'll save a lot of time.

Coils I'd be using are NF 15 evo and/or Detech 15 Ultimate DD

Pete.

No. Your detector will always pickup items below coil since lead is close to gold on periodic table you could not tell if it were gold or lead

Sorry

I have seen guys take off the first few inches to remove the issue

Bullets unfortunately produce too powerful a response in any timing. Smaller bits of foil, bird shot etc. can be ignored by using bigger coils and less sensitive timings such as Normal and Salt. For this purpose, the Salt timing on the 4500 is actually better than the salt on the 5000 due to be being less sensitive to small shallow targets.

I'd try the 15" Detech, Salt, and coil/Rx on DD

Thanks HH, that's pretty much what I thought but was hoping that the instructor knew something the majority didn't, can't recall his name but it was through Coiltek Maryborough and he had a lot to do with the testing of the GPX 5k and GPZ for minelab and also been full time prospecting in WA and doing instructional work here in the off season, big solid guy that reminded me of Shane Jacobson (Kenny) and a nice bloke. Maybe it was not so much settings but a way to determine if they were shallow or deep targets like lifting the coil over the target (?), can't quite recall as it was mentioned at the start of the day and there was so much to take in the following hours, it was only on my way home I remembered I'd forgotten to get him to show me how to ignore the shallow bullets.
Anyway, knew it would be too good to be true and I'll stick to digging everything.

Hi Nenad, that makes perfect sense and I'll give those settings a try, from the small amount of testing I've done with my coils that Detech 15 dd punches slightly deeper than my 15 evo on Factory settings (evo in Enhanced and dd in Normal) and I'll have the advantage of a cleared block so using hipstick/bungy and control arm should make the extra weight of this coil very manageable.

Thanks guys, it'll be a few weeks before I can get up there and maybe with the damp ground it might help gain and inch or two on the halo effect.