Modded GP3500 info?

Hi everyone,

I've recently purchased a GP3500 which ended up being a modded unit, the Minlab Manual has a letter from Detectormods.com stappled in the back. I wasn't looking/paying for a modded unit but found out on pickup that it is.

The letter lists mods to both depth boost settings and also 3 new timing settings.

I've found when set to deep detecting setting I'm digging seriously deep but no shallow finds. Vise-versa on shallow settings I'm finding that every two steps I'm hitting some form of target. This makes me think that maybe at deep settings I'm missing the bulk of smaller targets.

My question is for anyone with/without a modded GP3500:

Whats your day to day settings?
Do you perform multiple runs? One at shallow settings then back again at deep settings?

Any general tips would be greatly appreciated

Tim

Try giving Peter [Woody] a ring, or email him.
He is the one responsible for the mods and will give you advice.
His details are on his website.

Good point.

He has supplied a letter.

This GP has had a switch added that allows the detector to be optimized for either DEEP Gold, Medium Gold or Small Gold. The detector will show better signal response on deeper targets and more peaked response on small shallow targets.

summarised:

Deep Position = Ground noise cancel, small coil can then find smaller targets

Medium Position = Find medium gold perviously out of reach

Normal Position

Also a timing software boost switch has been added, which works for all new timings when the GP3500 is in SENSITIVE MODE

Use fixed tracking and re-balance every few minutes.

Woodys favorite setting - Sensitive, Deep and new timing switch to Medium.

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I've been using the listed favourite settings but I can still run in standard no mod modes and would like to hear what other users normally use. Also if they work the one spot with multiple runs at different settings.

Hey mate I've got a modded gp 3000 so I'll give you some advice. The deep, medium, small frequencies that you are talking about are used with different coils for different targets. E.g if your running in deep you need to be using a coil that is 20" or larger and at the other end of the spectrum if your chasing targets in small you need to be using an 8x6 or 6" coil.

Ahhh well thats not what I expected to hear lol

For now I only have an 11" so it will be medium then. Unless its noisy ground then I'll use the Deep setting. Thats making more sense now, the letter states Deep position will cancel most ground noise, thus even with a smaller coil deep will work well on small targets in noisy ground.

Thankyou sooo much for the info.

Hey, always use the deep setting it will give you the best chance on gold....in terms of nuggets you never know what size your going to get until you hear it (that's a skill in itself) It is also the clearest and most distinguishable boost option that the gp series detectors provide. yeah start out with it in medium for the 11" there is a chance you could get extra sensitivity in small so if you need an alternative later in the day try that. No worries kariong.

Cheers eve

Went out again today to a local beach and learn't a lot. The threshold in Deep was probably too quiet, I couldn't tune in any background noise (If that makes any sense). In Normal boost I could hear the threshold and dips of deep tiny targets. But Deeps got me sold, found a tone of coins which was fun. I noticed that if I faced any EMI sources i had a clear signal and found lots. Turned side on it was still clear but I was missing targets. At least it seemed that was the case.

I would have dug at least 4x 0.5 meter deep holes just to find a little 1cent or two cent coin and even a tiny little safety pin. I had a really nice cookoo sounding signal that ended up being a green rock. I took it home and smashed it up but no yellow.

Still a fun time, I had a line up of little kids hanging around me putting in their orders for rusty 5 cent coins. I found at least 8x 5c coins while they were lined up. lol they were just expecting me to find one every few minutes, which I actually was.

I've been running in slow tracking all day and Fixed BALANCE. Whats the benifit of running in fast? Does this function only work if your using Tracking BALANCE Mode?

kariong chill said:

I've been running in slow tracking all day and Fixed BALANCE. Whats the benifit of running in fast? Does this function only work if your using Tracking BALANCE Mode?

Click to expand...

The tracking speed will only have an effect while you are in tracking mode. Use the slowest speed that will keep up with the changes in the ground mineralisation. Most people would most likely be using slow or med while in tracking mode & it's really up to the operator + the ground under the coil as to what speed is better/required.
When in tracking mode you can use the quick track button to fix or stop the tracking by pressing & holding it in. This is good for pinpointing + checking targets & in particular faint targets that may otherwise be balanced out by the tracking mode. You will hear a beep when you release it indicating that you are going back into tracking mode. A quick auto track occurs when released also.

When in fixed the quick track button does a quick rebalance when depressed otherwise your "fixed" in the same balance state all the time. Changes in the ground or even a target can put your balance out so it's important to use the quick track button & re-ground balance frequently in fixed. After a while it becomes second nature.

Thanks Mbasko. I'll have to try TRACKING MODE next time out, so far I've stuck with the FIXED TRACKING and when I find a target I'm re-ground balancing near it. Seems to be working. After an hour or so I've been turning off the detector and re-tuning then ground balancing. Seems to help keep things settled.

Still a lot to learn

Gidday kariong, It's good to hear that your getting some coins and entertainment out of your gp3500 hundred . That's perfectly understandable with the threshold being faint at the beach...I actually thought you where a gold fields man/woman after all that is where you will get the most out of this machine. If you do get out to the gold fields the ground will be the polar opposite of what it is at the beach.

Cheers Eve

When going out on beach finds the GP3500 seems to take a very long time to get into a good mood. .

It seems to be the same pattern every time, I can't find anything but light weight caps/foil/can pieces in the first hour.

I went out today and as per the norm, I found around 8 bottle caps at two different beaches in the first hour.

Then nothing for half hour or so.

Then like always when I'm just about to give up it starts hitting coins... .

When I first walked onto the beach today I detected an area and didn't really find anything but at the end of the day I found at least 8 spots to dig in the same location.

Could this be a sign that somethings a bit wrong in the detector?

Or I just settle down and detect in a differnt manner?

Maybe a part of the learning curve?

A mate of mine has recently been given a modded GP3500 to use. He's running the SDC normally but would like to use the GP for a change & to go over areas where he's found/finding gold. Problem is there are no instructions for the mods with the machine & the owner never used it as he decided to get a GPX5000 instead. It's been sitting in his cupboard untouched for years.




Any information on who would have made these mods, how to use them in conjunction with the standard settings & anyone's experience using them would be appreciated.
Obviously one is a gain mod & the other presumably to adjust pulse frequency/sensitivity. We should be able to work them out but some recommendations or other info would be a help.

You could try here, Matt: http://www.minelabmods.com/joomla3/index.php

Ismael Jones' mobile number is on that site - maybe give him a call if you can't spot anything in the forum area.

Thanks mate - yeah I checked Ismaels site but no luck. If I don't do any good I'll get onto him. Even if it's not his work chances are he'd know.

Do the turbo boost gauges actually work? :8

:lol: not sure mate. He hasn't fired it up yet. Does look a bit funny hey - I've never seen anything like it.
I'm suss on mods at the best of times. My gut feeling is that it could have been a scam job? Thought I'd post it up & see if anyone had seen or used anything like it. I usually steer clear of mods altogether but seeing as though it was a freeby said I'd see what I could dig up. IMO best case would be if they did nothing but the machine still worked normally otherwise. If I get a chance to physically check it I'll know more or once he's had a chance to test run it.

Easy to use Matt, the little compasses point straight to the gold and the gain + 'recycle' function smelts your lead bullets into little ingots

If the mods are similar to others, then the higher the freq - supposedly better for smaller gold. Trade off is slightly lower depth.

The gain control will basically control the input gain to the first or second pre-amp.

If it were mine, I would set machine up with freq mid to high, gain mid way and set up rest as per standard manual.

If its a bit noisy just turn the gain down a little. If the ground is a bit deeper and after larger nuggets, try lower frequency.

Thanks SP I'll pass it on so he can try it out. I was actually thinking the other way for the frequency i.e. lower frequency more sensitive to small gold as per the Whites TDI's?
I guess it will be a bit of trial & error until we work out how it runs etc.

mbasko said:

Thanks SP I'll pass it on so he can try it out. I was actually thinking the other way for the frequency i.e. lower frequency more sensitive to small gold as per the Whites TDI's?
I guess it will be a bit of trial & error until we work out how it runs etc.

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Mbasko, I think you're mixing that up with the conductivity switch setting