coil sizes/hot ground

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Gday all.
As most of you probably know I'm a newby and I've been having a bit of luck with the 4500 with the 8" mono commander coil on the small stuff in a gully I've been working. I've started working the upper sides of the gully however the ground is incredibly hot. False signals left right and Centre even in sens smooth. I was wondering if the 18x12.5 nugget tech mono will better cope with this highly mieralised ground.
I have a hunch this is good ground as a large area has been chopped out at the top of the hill and I assume this was a large reef/ rich deposit (large quarts and ironstone below). The closer you get to this reef? The hottor the ground. I'm hoping the bigger coil will cope with the ground a little better due to balancing to a larger surface area? The larger coil would be much better suited to this location and there is little growth. Hoping to get out and grid the area thoroughly in search of a patch or a stray piece that didn't make it into the gully. A friend of mine found a fairly sharp edged piece yesterday nearby that hadn't traveled far. I'm hoping that this is gold that has been shed from the reef and not made it to the low spot of the gully as its not very steep. I'm hoping its not just tailings from the large cut out section with the odd missed nugget. However even if it is, I will quite happily pick up what was missed haha.
Sorry for the long post I just wanted to give you an idea of the area I am dealing with to get some advice.
Any info on coil sizes with regards to hot ground would be greatly appreciated. Was digging quite a few false signals yesterday as was my friend with his 7000. Interestingly the 7000 struggled with certain pockets of ground where the 4500 was fine in enhance. And the 4500 struggled in certain pockets of ground even in sens smooth and the 7000 was fine.
Cheers
 
You should be using a larger coil on the deeper ground ,stick with the 8 coil in the shallow ground its sensitivity is much better than larger coils .Just goes to show how all detectors are different as yours works OK on some ground and the Z plays up then the opposite on others ground.
I use my 4500 in enhanced most of the time run the audio in normal or quiet in bad ground back the gain to 9 same with the stabilizer ,target volume can make the detector noisy if set to high I find 12 is good for me regards john :)
 
Thanks for your reply john. Appreciate the info. It seems the ground on this hill is quite shallow. Although I'm more concerned with ground coverage and also coping with the hot ground. The 8" is dynamite around the diggings in the gully however isn't ideal for covering ground on the hill feeding the gully. The 8" is also carrying on as the ground is really hot and I wondered if a bigger coil will cope with the hot ground better. I don't think this ground can be overcome completely as its as hot as a priest in a primary school. However if I can get any improvements I'll be a happy man.
Thanks john
 
If looking for another coil I think that you cannot go past Nugget Finder coils buy new then you have piece of mind .
The test that I have seen done buy a friend with nugget tech coils I do not think that I would be using one anytime in the future
yes I can under stand what you are saying by wanting to cover ground but even with large coils you still have to work very slow listening for the brake in the threshold that deep targets give regards john :)
 
Thanks for the feedback john. I must admit I'm a little hesitant about the nugget tech after a bit of research online. However the coil came with my detector which is why I ask. Im heading out tomorrow and wondered if the bigger coil will cope with the hot ground any better than the 8". The beauty of the big coil is you cover more ground even when you are working slowly which is what I'm going for.
Cheers
 
Hey mate my 2 general size coils are an 11" round and 15x8 Detech mono which runs really quiet.
I find bigger coils in noisy ground just give a broader ground signal.
I run deep audio most of the time and if it gets noisy il drop it back to normal.
Another thing is if your have the front switch set to double d, flicking it to mono will quieten it down a touch also.
Edit: I'm talking mono coils here.
 
Thanks for the response timau. I might have a crack with the bigger coil tomora and see how I go. I did try to use it briefly on an overcast stormy day and the emi was off the hook. I've only got Mono's and run in mono along with normal audio. Might try dropping the target volume a touch as well as I'm well above FP settings at the minute. Been working a treat with the 8" on the small stuff.
Given how hot this ground is I don't think it can be overcome completely however if I can get any improvements I'll be happy. Appreciate the replies guys.
 
Yer try dropping everything back to FP, enhance, normal audio and adjust from there.
One thing I am only just learning is that you don't need to have everything cranked right up to find gold. I used to run a high gain and listen through the noise but dropping the gain down to where the machine runs smooth I'm still finding the same type of targets without having to work overtime listening through the noise. Makes a huge difference to the noise but I don't believe it has a significant loss on a good signal.
 
Completely agree mate. I run gain between FP and 11 depending on timing and ground. Stab stays in FP for the most part. I run all the audio in FP except for target volume on the last 2 outings.
I'm believe running the machine smooth is a huge advantage for picking those faint signals. Most of my gold was found at FP settings or very close to. You really can't go wrong with the FP settings. I find being in the correct timing for the ground is the most important setting.
 
Just my 2 cents, I was running the stock 8inch mono on my F1A4 and it was picking up a lot of noise in mineralised spots, switched to the 16inch Coiltek and she ran super quiet...so would def recommend the coil change. The 8inch was signalling on all sorts of small iron stone ground, the bigger coil really smoothed out those false signals.
 
Yea I found the same thing mate. Must be due to the small coil ground balancing to a small surface area and being extra sensitive to any variation in mineralization. I couldn't handle the big coil. The cut outs in it were driving me mental getting caught on sticks and what not. I put the 8" back on and went to different ground and picked up 2 nuggets. I'll have to get myself a bigger enclosed mono for this particular ground. Thanks for the responses
 
The 14" nugget finder is a quiet coil to use.

Just a question.

What are the first 4 numbers of your serial
Numbers for the 4500?
 
Regardless of coil size, if you are in ground where even Sens Smooth is giving you headaches, give Specific Ground Balance a try. Has worked for me in some spots around Talbot / Amherst
 

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