Minelab GPX4500 tips, settings, questions

[Davent]

you beauty, thats the knd of answer im looking for, ta.

 

[old hand]

Dave I would run inverted, target vol 12 and audio in normal I find in deep it broadens the signal making hard to tell if its a target or mineral the 12 x15 are a great coil good luck regards john

 

[BigWave]

Every ground is different Dave. I know zip about NT ground.
In the GT of VIC with my 4590, I pretty much stay in Enhance, Deep, Slow and Quiet. I sometimes get the Rx gain to 14, but keep the stabiliser around 2 settings lower.

 

[Davent]

Ground varies up here from undetetctable constant racket to very very mild.
The area I will be working is fairly mild, with a few loud spots. The loudest spots in this area are around the cap of latarite, which is also pretty shallow.I found a small piece on the edge of the cap. I dont know if im describing it properly, what I call the cap is kind of like bed rock, but you can breakthrough that and there are more layers....im hitting it again on tuesday, and will photogrraph the area, its pretty uniquie , in that its very different to the surround ing country. Taking a mate with me this time, I was suffering from heat last time, and ive lived here for 17 years. It a wierd time of the year, not wet season, but still humid, like the build up, but little cloud cover or shade.
Guess ill be mucking around with settings, if it all gets too hard, ill go go back to factory, try normal, and tweak the gain and stab a bit, if that fails, go back to 14 x 9 and slow right down.

 

[Dignit]

G'day Dave
The settings I use are the same as BigWaves. I got these of Mark from Gold Prospecting Australia who I spent some money with to get professional tuition when I first got my 4500. The settings serve me well. I have tried just about every other setting but go back to these. Mind you I'm in Vic GT and every location can be different and a lot of people have there own preferred settings. I have the 15x12 & 11 & 8" commander monos, and an elite 11 mono. Use the same settings on them all, just adjust the gain and Stabilizer to suit.
Good luck. Cheers Dignit

 

[Davent]

Thanks for that, there is no one to get "lessons" from here, so I have to read and muck around myself, its pretty hard when your not finding gold, to know if your settings are right. But when I turned up the little piece the other day, it gave me some good confidence.

 

[Heatho]

Normal is generally not the best timing for mono coils, yeah you can use it but you'll get a lot of hotrocks if they are there, a lot more EMI and will be impossible to run on noisy ground. Give it a go but just flick back to Enhance if it gets too noisy.

Even try a DD in SensExtra or Normal.

 

[Davent]

Ok, ive mainly used enhance so far, and been pretty happy with that, but because I want to maximise depth with what I have, thought normal might be worth a go. I did get some hot rocks last time in normal at a different spot.
The 12 x 15 is my biggest coil atm, will get a 14" elite, or 15 nf evo if I can, but wont have one by tuesday. From what I can gather, the new coils wont get much deeper than the 12 x 15, but are more sensitive to the smaller stuff. Im planning to go over the area thougholy for deeper bigger gold 1st, the do it again with the 14 x 9 nf for the smaller after. My mate will be using my tdi pro oz with a razor back 10 x 6

 

[10fp]

Good luck , run Hot mate

and lets us know how you go with the 15x12 and what settings you end up using in your area there

Dave

 

[Davent]

Gday, was working some hot ground (patchy hot) and was wondering the correct way to use the stab .

I was using the 15 x 12, in enhance, gain was 13, stab was 11.
Turned gain down to 11 stab to 9, still couldn't quiet the coil down.

So was wondering if someone might give me a little tuition on here, as there is no where here where I can pay to learn the machine, or I would do a day or 2 training.
Cheers.

 

[old hand]

Hi Dave what state do you live regards john

 

[Davent]

NT, Darwin

 

[old hand]

to far to meet up dave

 

[Heatho]

Can be difficult to quiten down gpx's sometimes was it EMI or ground noise?

You can keep doing auto tunes and hope it picks a good channel or try to manually do it. Dropping the gain down a bit more and dropping the stabiliser more can help too. Nenad usually recommends dropping the gain down to even say 5 (I think) if conditions are poor. Some others recommend dropping the stabiliser right down to 5 sometimes too and leaving the gain around 8-10, it's a real balancing act sometimes. Sometimes smaller coils can help. Sometimes have to drop to sens/smooth, though I've never had to do that though.

Remember though that the higher the stailiser number the less it is working, 20 is off, 1 is full.

 

[user 4485]

GPX 5000 & GPX 4800: What is the purpose of the Stabilizer control?

The Stabilizer function controls the point at which faint variations in the Threshold begin to be heard. These faint variations can either be ambient noise or faint target signals. As you increase the Stabilizer control, faint target signals will become louder, but the noise level will also increase, which may potentially hide a desirable target signal. The Stabilizer allows you to mask these faint variations to provide a perfectly stable threshold, improving your ability to identify faint target signals.

The Stabilizer is best left in the FP (factory preset) position until the soil conditions in the location are determined. Once the Rx Gain level has been set for the local conditions and other audio settings have been selected, the Stabilizer can then be used to fine tune the Threshold stability.

To find the optimal position of the Stabilizer, ensure that the coil is being swept across the ground. One number below the point at which the threshold begins to chatter, is generally the best setting.

The effect of the Stabilizer could be seen as having a similar effect to that of the Rx Gain control. However, the Stabilizer affects the audio processing only and does not change the Receive (Rx) signal, so should be used as a final stage fine tune. After making any adjustments to the Stabilizer, if the ground conditions change or you wish to change coils, you may need to reset the Rx Gain, but before doing so, return the Stabilizer to the Factory Preset setting first. This will ensure you select the most appropriate Rx Gain level to suit the conditions, and then you can fine tune using the Stabilizer.

Tip: By turning the Stabilizer control close to minimum (anti-clockwise) the threshold will be very stable, but you will have lost a lot of sensitivity to smaller targets. This can be a desirable feature in certain scenarios such as looking for large nuggets in a high-trash area, or using the GPX 5000 and GPX 4800 to search for coins or treasure.

Tip: We would recommend the best order for setting these controls are:
1. Select an appropriate Search Mode
2. Select the desired Audio Type
3. Adjust Rx Gain until the threshold starts to break up
4. Adjust Stabilizer to smooth out the threshold.

 

[Nightjar]

GPX 5000 & GPX 4800: What is the purpose of the Stabilizer control?


Tip: We would recommend the best order for setting these controls are:
1. Select an appropriate Search Mode
2. Select the desired Audio Type
3. Adjust Rx Gain until the threshold starts to break up
4. Adjust Stabilizer to smooth out the threshold.

This is what we always use. If a faint signal is heard, crank the Rx up to max, if the signal improves greatly. DIG!

 

[Mickybees]

Gday, was working some hot ground (patchy hot) and was wondering the correct way to use the stab .

I was using the 15 x 12, in enhance, gain was 13, stab was 11.
Turned gain down to 11 stab to 9, still couldn't quiet the coil down.

So was wondering if someone might give me a little tuition on here, as there is no where here where I can pay to learn the machine, or I would do a day or 2 training.
Cheers.

Hi there's a few ways to run your machine i run my rx high anywhere between 13 and 15 which is max I back my stabiliser down to where the machine runs smooth depending on the ground Iv had the stabiliser down to 3 and I didn't notice no lack of depth or anything it still ran perfect..I use to run my machine like you keep my stabiliser 2 down from my rx but I got shown the other way off an expirenced prospector and Iv been running like that ever since give it a try and see how you go ..

 

[user 4485]

My favourite settings for my area were gain 14 stab 8 (GPX5000). Seemed to work well in a lot of areas but something you need to play with to suit your area/conditions.
I've heard of trainers rolling out the old keep the stab 2 below your gain line & IMO it's crap. Keep your stab where the machine runs nicely for you.

 

[Davent]

Ok, so the lower the stab number, the more influence right?
will start at 1 and keep adding untill it starts to warble, then drop one, see how that goes?
could have been a bad day, emi, rain to the north of us, no electricial storm though, army activity.,.
even road trains on cb, s. I think that the ground isnt too bad, but there are pockets of very difficult ground.
I probably just couldnt hear gold through the noise, wasted a day....well not really wasted, guess I learned something.
thanks for all the replies and advice, will keep at it!

oh, and old hand, I tried inverted, still, set on that atm. Could inverted kinda be a way of discriminating?

 

[northerngold]

That's some great information
Thanks guys