GPX4500 Possible Coil Issue?

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Rustyone

Russ
Joined
Jul 12, 2015
Messages
10
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Location
Nowra, NSW
Hi all,
Have a 4500 and my 11 mono finally crashed ( worst coil I'd ever had...so noisy due to crap connections). I switched to the DD and all was good until I stopped for a break. When I turned it back on there was a huge squeal about 2 seconds later, that continued. I tried to auto tuned but it just squealed continuously. I turned it off and then on again. Still had the big squeal but then it settled down. I did a test sweep but it wouldnt even pick up the metal in my pick. Off again and switched it to Mono. Big squeal again and then settled. After a test, it picked up my pick but it was a very low signal, very low.
My question: Is this a Coil or detector issue?. Im just worried that there is an issue with my 4500 that has cooked both coils.Only used the DD as back up or in HTP areas and it's only been used 4-5 times). Any advice appreciated.

Thanks in advance.

RustyAu
 
Hi Rusty,

If you put your 11" mono on, does it still work? I take it that it was bump sensitive?
If you just sit it on the ground and wave a target over it does it give normal depth?(coil switch in mono)
If you switch the coil switch to DD does it still detect the target ok?
If so, then your detector is likely fine.

It is possible that the DD coil may have a bad connection in the plug if it has only been used a few times.

Your detector won't fry a coil, the detector will fry long before the coil does!

Cheers Mick
 
Go to a dealer or find someone with a similar detector.

I had an issue with my 5000 audio, went to a dealer who got one of their rentals out. We tried swapping various items in the mix to eventually find the audio amp card in the battery was the issue.

The GPX can be broken down to 4 areas - Detector box, Coil, Battery or Phones/Speaker.

Or send the whole lot back to Minelab if it is still under warranty.
 
Rusty, Check out the curly cable from the battery to the detector. This is the one thing that I know to fail from time to time due to the amount of bending it gets every day and especially when you catch it on a branch or something. I've met more than one guy who had the cable damaged but continued to use it causing the audio section of the battery to fail. If the cable is making a poor contact, stop and fix it before going further.
 
Hi all,
Thanks for the feedback. A bit of trial and error in my future, I'm thinking. While I've got you, I like the round 11" as I work in a lot of heavily timbered and scrub areas so the edge of the 11" round can get into those nooks and crannies around the tree stumps..How are the elliptical coils around the edges if I turn it on the side?
Thanks again.

Rusty
 
Hi AuMan.
yep, the mono was very bump sensitive. Must of been one of the bad batches of coils a few years ago. That was an easy fix. I had it apart checked the solder joint and re-secured everything and used conductive paste, sealed the shield and components etc. It was still sensitive to bumps but not as bad. That's when I found that the connection to the machine was very sloppy. The connection ring was tight but there was still a lot of play in the connection.The bump would transmit through the cable to the connection.As you can appreciate, in heavy scrub/timber I bumped the coil a lot.. Plumbers tape (teflon) fixed the connect ring issue and a lot of electrical tape to secure the cable to the shaft. It still got worse over time though. Just a poorly made coil all round. Never had a problem with the DD until last weekend.

Rusty
[User is Offline] AuMan
 
A 14x9 Nugget Finder Evolution elliptical will give approx. the same depth as the 11" Commander. It will however be more sensitive to smaller gold and get into the tighter spots easier.
 
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