First Afternoon Using The Goldhawk 10x5 Mono

[Aureous]

@GotAU? The shield I have right now is passive, no ground connected. But, to do it completely right, ya gotta run a wire from the shield to the earth wire which is taped to the graphite-paint shield on the inside of the control box. To do this, ya gotta crack open the box and 'presto', your warranty is null and void . I'm gonna try and 'double up' and apply copper tape direct to the control box exterior (provided that it peels off Okay).

Y axis noise is the Earths own magnetic field being detected by the coil. It runs parallel to the ground. You tilt the coil off its preferred 'X Axis' and it appears, more or less depending on the detector type and coil type. 

[phrunt]

It was easier with the GPX 4500/5000 where the screws holding the front and rear fascias on touched the alloy shielding and metal housing which was the floating ground.  The 6000 housing shielding is very basic with just some shielding paint on the plastic housing, you'd really need to shield to the PCB, and can't without voiding warranty.

So really, not much can be done.

 

[GotAU?]

29 minutes ago, phrunt said:

It was easier with the GPX 4500/5000 where the screws holding the front and rear fascias on touched the alloy shielding and metal housing which was the floating ground.  The 6000 housing shielding is very basic with just some shielding paint on the plastic housing, you'd really need to shield to the PCB, and can't without voiding warranty.

So really, not much can be done.

 

So if the shield has to go to the PCB ground, I wonder if the speaker ground goes there as well?  May be a ground point doing that.

I’m thinking of trying Aureous’ passive shield idea also  by modifying the inside of My Doc’s cover.

[GotAU?]

50 minutes ago, Aureous said:

@GotAU? The shield I have right now is passive, no ground connected. But, to do it completely right, ya gotta run a wire from the shield to the earth wire which is taped to the graphite-paint shield on the inside of the control box. To do this, ya gotta crack open the box and 'presto', your warranty is null and void . I'm gonna try and 'double up' and apply copper tape direct to the control box exterior (provided that it peels off Okay).

Y axis noise is the Earths own magnetic field being detected by the coil. It runs parallel to the ground. You tilt the coil off its preferred 'X Axis' and it appears, more or less depending on the detector type and coil type. 

Thanks for the reply.  And wow, the Earth’s magnetic field? That’s pretty interesting, especially as detectors become a lot more sensitive to things like that.

I am thinking of trying your passive shield idea with my Doc’s cover also after your trial, so please post about the results!

[GB_Amateur]

5 hours ago, Aureous said:

I'm gonna try and 'double up' and apply copper tape direct to the control box exterior (provided that it peels off Okay).

I assume you intend to use the kind with conductive adhesive, but since both kinds are sold it's worth a mention for others who may not be aware of its importance.

[GotAU?]

The type I want to try, by sticking it on the insides of my Doc’s cover, is aluminum duct tape used by heating suppliers. I’ll have to be sure that there’s conductivity between the strips, perhaps by bending the corners down over each other, but it should work out pretty well as a shield.

while I’m at it, I’ll make a stick on foil hat for my head!🤪

[phrunt]

9 hours ago, GotAU? said:

So if the shield has to go to the PCB ground, I wonder if the speaker ground goes there as well?  May be a ground point doing that.

I’m thinking of trying Aureous’ passive shield idea also  by modifying the inside of My Doc’s cover.

Speakers negative is a common ground connection normally.  I don't think it will make much difference as most of the EMI is likely from the coil.

[dig4gold]

Why didn't minelab do their best to provide the best of shielding for such an expensive detector?

D4G

 

[GotAU?]

8 minutes ago, phrunt said:

Speakers negative is a common ground connection normally.  I don't think it will make much difference as most of the EMI is likely from the coil.

Have you had to do those weird blips every so often randomly, some people say there’s an airplane nearby. That’s kind of hard to tell from me because there are always airplanes nearby where we are.

[phrunt]

26 minutes ago, dig4gold said:

Why didn't minelab do their best to provide the best of shielding for such an expensive detector?

It's possible they have, modern electronics less prone to EMI interference, the shielding paint maybe all that's needed.  On the older GPX with the thick foil on the ends with the metal housing they had really good shielding, yet the detector was far more prone to EMI than the 6000, so somethings changed.  I'm pretty happy with my 6000 in higher EMI areas, such an improvement over older GPX's

This is the foil ends off the old GPX under the plastic covers

These are connected to the alloy housing, a mistake they made on early GPX 4500's was the blue paint for the housing went over the ends of the housing from being sprayed on, so this shield was touching the paint, not the raw metal thereby the shielding was poor relying on the screws, I scraped the paint off mine on the ends, and it improved it's EMI handling.  I've noticed on my 5000 the paint isn't over the ends.

I also have one of these which add extra shielding, many thought they're a gimmick but they're not, they do genuinely work, I did connect a wire from it to the shield by a screw terminal though, they don't mention you need to do this and you just put it on as a cover but it's the best way to connect it to the ground of the detector for best results.

.

 

It's a cool idea trying to improve the shielding, I'd like to see someone try and if they get any success that's awesome and the feedback should go to Minelab however I'm not sure how much extra shielding would help.  With the right coil, I find the 6000 to be pretty good for EMI, especially for a PI and now the EMI Audio fix has been done.

@GotAU? Are you using a Torus Neck speaker? It can cause the blips with it's aptX LL glitching when the data rate doesn't keep up so you get a blip or crackle as a broken signal, it's an acknowledged issue with them that can't be fixed and one of the reasons atpX LL is gone and Bluetooth LE now exists.  Qualcomm that made aptX LL discontinued it to make aptX Adaptive which resolves this blip problem but it's not as good for detectors as it's latency being slower and moving around to different latency speeds depending on signal strength so Qualcomm is out of the detector game now with standard Bluetooth's new version now being better than a proprietary codec.  The Torus seems more prone to blipping than any other aptX product I've got.