GPX Coil Opinion Request

[jasong]

What are you running your stabilizer at? Might stabilize it some more if you are in or near cities.

EMI does change in some places by time of day. Some interference can come from far off and be more intense at closer to night, like why AM radio stations have to reduce their broadcast power at night because propagation increases due to interactions with the ionosphere. Noise of certain frequencies also increases propagation distance and so in some places you'll start hearing a lot more in the evening.

Thanks for the test with the 14x9 and 8", good to know. A 14x9 hitting a .1 gram nugget at 3.5" in bad ground is pretty impressive really, even if it was outperformed by the 8", you can cover almost twice the ground..

[Roughwater]

4 hours ago, jasong said:

What are you running your stabilizer at? Might stabilize it some more if you are in or near cities.

I was running the Stablizer very low most of the time.  Often at 1 or a high of 5. For whatever reason, to my ear, the EMI seemed to lesson with turning the stabilizer lower.  It also got lower with turning other things down but unfortunately I think the signal level also got lower.  I probably should have tested my DD coils in cancel when the EMI went higher but I didn't think to at the time. 

I was doing a little search on coils and came across this post which seemed like good general info from folks testing coils down under.

Terry

[Roughwater]

4 hours ago, jasong said:

What are you running your stabilizer at? Might stabilize it some more if you are in or near cities.

I was running the Stablizer very low most of the time.  Often at 1 or a high of 5. For whatever reason, to my ear, the EMI seemed to lesson with turning the stabilizer lower.  It also got lower with turning other things down but unfortunately I think the signal level also got lower.  I probably should have tested my DD coils in cancel when the EMI went higher but I didn't think to at the time. 

Again this ground maybe the worst I have ever hunted on.  It's full of little hot rocks that stick to my pick when ever I dig here.  When I was trying to do an air test using the 5000 and the 14X9 Evo I tried waving one of the hot rocks that had stuck to the pick magnet in front of the coil.  It would detect it close to the coil but of course when you ground balance it to the actual hot ground it balances those out but at the same time I figure it's desensitizing the detector/coil as well.  This makes me feel like the 14X9 is a really sensitive coil but can be no more sensitive than the detector/ground conditions/EMI allows it to be.  

I was doing a little search on coils and came across this link which seemed like good general info from folks testing coils down under.

http://golddetecting.4umer.net/t398-testing-coils-mono-and-dd

 

I added this link as an Edit.  It is a very old post but the basics of the coil for a SD, GP or GPX is the same today as it was back when.  The GP and GPX however give the detector a little more adjustment for depth and or sensitivity. Most of you know this already but some may not and for myself being older and getting back to detecting it's a good review. 

http://www.docsdetecting.com/docsplace/jlange/confusion.html

 

Terry

[Andrey]

On June 28, 2016 at 0:31 AM, jasong said:

What are you running your stabilizer at? Might stabilize it some more if you are in or near cities.

EMI does change in some places by time of day. Some interference can come from far off and be more intense at closer to night, like why AM radio stations have to reduce their broadcast power at night because propagation increases due to interactions with the ionosphere. Noise of certain frequencies also increases propagation distance and so in some places you'll start hearing a lot more in the evening.

Thanks for the test with the 14x9 and 8", good to know. A 14x9 hitting a .1 gram nugget at 3.5" in bad ground is pretty impressive really, even if it was outperformed by the 8", you can cover almost twice the ground..

 

I noticed that in the evening I hear less noise.

[bado1]

As has been discussed you do not want to run your stabilizer too low ....below 7.  You will lose smaller targets when you do.

I would suggest that you read the manual, then re read it. If you are trying to test in the city it won't work. Too much EMI.

If you are out in the boonies and still can't get a stable threshold start by lowering the gain. I can run near those huge power lines and obtain a stable threshold with my stabilizer at 9 with a 14x9 coil. Check your other settings first.

 

Dean

[PhaseTech]

On 9/17/2016 at 12:52 PM, bado1 said:

As has been discussed you do not want to run your stabilizer too low ....below 7.  You will lose smaller targets when you do.

I would suggest that you read the manual, then re read it. If you are trying to test in the city it won't work. Too much EMI.

If you are out in the boonies and still can't get a stable threshold start by lowering the gain. I can run near those huge power lines and obtain a stable threshold with my stabilizer at 9 with a 14x9 coil. Check your other settings first.

Dean

Thread recovery! Just had to bring this back up. What Dean says is spot on. Especially on the new generation of spiral wind coils, you don't want to overcook your Rx Gain. 

Smaller coils, and lower Rx Gain are you two best combats against EMI. Oh, and the old DD coil that most seem to have abandoned