GP 3500 Current Status In The Line Up

[DigsAlot]

I think the 14 x 9 and the Sadie are going to be  my coils that I use the most.

Thanks for the info gents.

[schiara]

I would highly recommend Doc’s Gold Screamer Power Pack, Li-Ion Battery System for Minelab PI’s, Although they are pricey, its worth it.

https://www.robsdetectors.com/docs-gold-screamer-power-pack/

[DigsAlot]

21 hours ago, schiara said:

I would highly recommend Doc’s Gold Screamer Power Pack, Li-Ion Battery System for Minelab PI’s, Although they are pricey, its worth it.

https://www.robsdetectors.com/docs-gold-screamer-power-pack/

I will give this a look over. Thank you for the advise.

[DigsAlot]

So I plan to go out with the GP 3500 this weekend, wondering if anyone had some good settings for small shallow gold in the northern nv type soil?

Perhaps Steve lol

[PhaseTech]

Here's what worked for me when I was swinging a 3500. These settings will work equally well with small - medium mono coils and the stock DD coil. 

Set your controls to the following settings:

Signal control - just off maximum (in noisy environments you may need to turn it down to 2 o'clock) 
Tone - the highest setting you are comfortable with. My preference was 3-4 o'clock
Volume - 4 o'clock
Threshold - just audible, but smooth - if it is breaking up it is too low
Coil - Mono
Soil - Sensitive
Ground - Fixed

If the ground allows it you can use Deep boost, but if it upsets the stability of the threshold, use Normal. 

Ground Balance as often as practical, and avoid running in Tracking if at all possible. 

Perform an Auto Tune as often as necessary. The most important aspect to the tuning process is to ensure the coil is held motionless. The easiest method I find is to turn the coil at 90 deg. and find the loudest direction of interference, and then place the whole detector on the ground, with the coil still vertical. With the GP 3500, you can keep the detector tuned by using the Manual Tune control. 

When you get a faint signal that you suspect may be a small nugget, play with the audio controls and see if a few small tweaks improve the signal response.
 

[Northeast]

Hi Nenad. 

I don't have a 3500 and am unlikely to ever but one thing stood out in the bit I read above. 

13 minutes ago, PhaseTech said:

Ground Balance as often as practical, and avoid running in Tracking if at all possible. 

I often see that Minelab tracking has been heralded as being pretty awesome.  Not so with the earlier models such as the 3500?  About when did tracking really step up to the plate? 

[PhaseTech]

The tracking has always been good, it is just the danger of tracking out a target is always greater when using a mono coil. Small low conductive targets, and the higher the mineralisation, the greater the risk! 

On the SD2200 series, the tracking was a slower rate, and as the 2200 hates mono coils (except for really mild ground) most people never took it out of tracking.  On the GP extreme and 3000 it was a faster rate, I guess it had to be because the machines were more sensitive. The Level adjust allowed the user to control the tracking to some extent, but most found this confusing, so 3 x speeds were introduced on the 3500 (with the Level Adjust being pre-set). 

Using a DD coil, I have never had a nugget track out (that I've noticed), but have noticed several times using a Mono. Not instantaneous, maybe 5-7 sweeps and the target was totally gone. Re-balance off to the side, check again, and yep target still there. Dig it up, and sure enough it's gold. This is reduced with the slower tracking speeds, but the only way to remove the risk all-together is to use Fixed and re-balance as often as you can remember. 

[Northeast]

Thanks for the response Nenad. 

I'll probably never own anything from that line up of detectors but interesting to know and hopefully helps somebody who does/is looking to use them.  

Thanks again. 

[PhaseTech]

Oh for sure. In very mild wash, you can put a new gen spiral coil on the 3500, run it in Sens and Deep and it will pretty much match what a GPX can do, minus the extra bit you can squeeze out of a 4500 and 5000. 

I hope you didn't just leave your 3000 in Sensitive though, as Normal has a clear advantage over the more conductive bits. Even some as small as say a flat half gram piece. 

[Joe76]

On 4/2/2018 at 10:18 PM, PhaseTech said:

Here's what worked for me when I was swinging a 3500. These settings will work equally well with small - medium mono coils and the stock DD coil. 

Set your controls to the following settings:

Signal control - just off maximum (in noisy environments you may need to turn it down to 2 o'clock) 
Tone - the highest setting you are comfortable with. My preference was 3-4 o'clock
Volume - 4 o'clock
Threshold - just audible, but smooth - if it is breaking up it is too low
Coil - Mono
Soil - Sensitive
Ground - Fixed

If the ground allows it you can use Deep boost, but if it upsets the stability of the threshold, use Normal. 

Ground Balance as often as practical, and avoid running in Tracking if at all possible. 

Perform an Auto Tune as often as necessary. The most important aspect to the tuning process is to ensure the coil is held motionless. The easiest method I find is to turn the coil at 90 deg. and find the loudest direction of interference, and then place the whole detector on the ground, with the coil still vertical. With the GP 3500, you can keep the detector tuned by using the Manual Tune control. 

When you get a faint signal that you suspect may be a small nugget, play with the audio controls and see if a few small tweaks improve the signal response.
 

Hi Nenad,

I have a question about running a gp3500 in tracking, I have a patch I found some years ago when I was using my gpx5000 with some really nice gold coming off it, like the 2 ounce bit in my profile pic. The ground is so hot and variable that enhance & fine gold struggled even dialling down settings. A took a mate out there just for a day so he could find a bit with his ZED & it too had trouble over the same ground having to drop sensitivity right back to try & cope. I haven't encountered groud like it before. Since then I sold my 5k through not being able to get out and use it but still own a gp3500. Now I am back on the hunt again, I was wondering if you had any experience using a gp3500 running in tracking using a DD coil opposed to fixed & if this may work in this situation as this ground seems to be nearly impossible to work at times.

I did some tests with a 0.3 piece using my Detech 15" spiral dd running in tracking & what I found I couldn't track out the nugget in dd mode. I'm yet to test my Detech 11" spiral mono using tracking. But I am hopeful over this super hot ground the gp3500 may have a chance if I can use tracking using a dd coil. If you have any advice you could share with me using the 35, it would be much appreciated.

Cheers Joe