Brand new GPX5000 - Non-stop EMI noise?

OK so I bought a new GPX5000 (from reputable dealer)... turned it on and its just screaming, sounds like crazy EMI.... I tested it in my yard which is in the hills.... also i drove out of town to see if EMI stopped... same thing. Its just non stop random crazy sounds. I have pressed the button to pick a channel, they are all noisy, non stop noise.

If I hold the detector in the air, out in front of me.... the noise is still there, so I presume its EMI?

What could be causing this? I live in a low density area and my old SD2000 gets hardly any EMI where I live.

Here is a link to a video of the noise it is making. Please ignore the fact that detector is inside, it makes the same sound anywhere I go, even in the bush. Just did it inside cause of mosquitos.

https://www.youtube.com/watch?v=lh10I0aJ_PE

HI Alistair,

Have you tried another coil on it? If you have or do and it still does it I would be marching back to the dealer you got it off or sending it direct to ML.
I doubt it would be emi with the detector in the factory state. Also have you done a factory reset?

Cheers Mick

Agree with Mick here also Alastair.
A faulty coil or coil lead connection. If you're a couple of hundred meters away from any overhead power lines/high voltage transformer,or underground cable then you should not be experiencing what you are. Also check to see that you haven't any electronic device such that of a switched on walkie talkie,mobile phone or pin-pointer for that matter,attached to,or close to your control box,which can cause constant EMI hum to come through your head phones/speaker?   
I can't think of anything else that could cause you constant EMI issues up switch on. Maybe someone else here can?  

Cheers Kon.

Mechanic wrote:HI Alistair,

Have you tried another coil on it? If you have or do and it still does it I would be marching back to the dealer you got it off or sending it direct to ML.
I doubt it would be emi with the detector in the factory state. Also have you done a factory reset?

Cheers Mick

Yes I have tried 2 coils.

Then it's a definite control box issue. Back to the factory for a check up it goes.

Cheers Kon.

Here is a link to a video of the noise it is making. Please ignore the fact that detector is inside, it makes the same sound anywhere I go, even in the bush. Just did it inside cause of mosquitos. How is it possible that they would make a metal detector that is not able to be used a built up environment... surely there should be a setting to emulate an older detector such as SD2000 which works fine in the garden for finding water pipes etc.

https://www.youtube.com/watch?v=lh10I0aJ_PE

If that's what it is doing out bush as well, then there is a fault with the unit.
Out of curiosity, does switching the receive switch to cancel have any effect?
Will be interested to hear how you get on sending it back and turn around time.

Cheers Mick

Fair enough Alastair,but that's exactly what they all do,in doors surrounded by live electrical's,more so with mono coils But as was said,It should not happen when you move a certain distance away from all live electrical cable activity.The detector should come to a quiet stable hum.(threshold wise that is)

Cheers Kon.

Mechanic wrote:If that's what it is doing out bush as well, then there is a fault with the unit.
Out of curiosity, does switching the receive switch to cancel have any effect?
Will be interested to hear how you get on sending it back and turn around time.

Cheers Mick

Cancel mode it goes quiet

Try holding the power switch on for up to 15 seconds - "factory reset".

Mine does that exact same thing when I switch it on and I am in suburbia, but out bush it goes quiet as. If you're driving out of town, and there is no other building for 500 meters around and no electric fences, no power lines, no underground telecom cables, and all you can hear is the sound of the birds, then it should be quiet, so long as you have it ground balances and in fine gold or enhanced. If the dealer isn't too far away, I would be taking it back there rather than Minelab and expecting then to give you another machine, so long as it's within days of buying it.

Alastair78 wrote:

Mechanic wrote:If that's what it is doing out bush as well, then there is a fault with the unit.
Out of curiosity, does switching the receive switch to cancel have any effect?
Will be interested to hear how you get on sending it back and turn around time.

Cheers Mick

Cancel mode it goes quiet

Ok, now try cancel with a DD coil. Also try with a DD coil set to DD mode then mono mode.
If it is quiet in DD but noisy in cancel and mono this indicates an internal source for the noise, if it is quiet in Cancel and noisy in mono/DD then the noise is external.

Since the detector went quiet by switching to cancel(you had a mono coil on?) it indicates that the noise is heard by both preamps(mono and DD preamps) so that leaves it to either a fault with the transmitter for an internal fault or the area you tested at out bush has a phone line somewhere close by, or you were too close to your car and something in it was powered on(fridge) emitting noise, or you had something on your person that was interfering.

Cheers Mick

There's some good information in some of these old posts.
I have a query.
I have never powered up a detector without the coil attached because all the manuals warn us not to, damage may result. Does anyone know what damage can be done by doing this?
There is one on Ebay right now, very well kept LCD screen shows it's turned on without the coil.
A good question for you Kon respecting your knowledge.

Hi Butch,

No damage results from powering up a detector without the coil attached. I do it every other day.

What can cause damage is unplugging the coil while the detector is running, though the GP and GPX detectors are pretty well protected against this, but I still wouldn't try it.

That being said, any damage caused by such events is repairable.

Cheers Mick

Thanks M takes a weight off.