Makro GR40 coil

[ProspectorPete]

Testing out my new GR40 coil in the Vic Gold Fields the past couple of days, I've only got about 4 hours on this coil so far and look forward to trying it out in different locations in the future but so far I like it.
When I first put the coil on it was super sensitive and I had to run the settings Sens 56, iSat 8, Thresh 30, Tracking off. After some time on the coil I was able to run settings at Sens 70, iSat 7, Thresh 27 but it also depends greatly on the ground being detected.
The coil was hitting many trash targets within the top 3" of ground but when testing on an old bottle top on the ground it would hit it with the coil raised to about knee high (15 - 18") so it should hit deep targets if they are there.

Pin Pointing is really easy on this big coil, there's 3 bars across the front centre of the coil and it is the most sensitive part, surprising how easy pin pointing actually is with it, as easy as the GR26 & GR19 coils.

At first I thought I'd made a mistake buying the new coil, it was a pig to get it to settle and I had to dumb down the settings that much there was no advantage to using it over the GR26 coil but after an hour running and gradually tweaking the settings it was running very stable and I felt confident using it, I need to put more hours on it in different locations to feel I know when and where to use it, I'm now glad it's in my coil box as I feel I've got a good range of terrain covered with the 3 GR coils.
On my .08g test piece the GR40 (with dumbed down settings) is no match for the GR26 but on bigger deeper targets it should come into it's own, and for covering open ground it's the go to coil, being an open spoke coil didn't seem to bother me and I was running it through a fair bit of scrub, the amount of surface matter in areas meant not getting the coil on the ground but it wouldn't matter what coil was being used, raking the area would be the only option.
The coil is also very bump sensitive but maybe the way I run the lead doesn't help.

The weight of the GR40 when fitted really makes the Gold Racer front heavy, I could swing for about 20 minutes before the right arm starts to ache, I have a JP harness, hip stick and bungy chord and it really makes a big difference, I could swing all day using it on flat ground but if detecting uneven ground or around mullock heaps the bungy is of little help.

Anyway, I hope this helps in some way, I'm a long way off getting the most from this coil and time will be the test, as the year goes on and I get more hours on the GR40 I'll keep posting my thoughts in this thread to hopefully help anyone contemplating buying one, I'm glad I did and look forward to more trips and hours using it.

[video=480,360]http://youtu.be/597fWgupE54[/video]

 

[Jim.]

Hi PP, great review on the GR40 coil. You might consider running in tracking mode when using the big coil, I've tried it with the standard coil and it works really well, there was no evidence of tracking targets out. I'm keen to get out with my Makro and all of my coils but we are having extreme weather (heat) at the moment and it's really not worth the pain.
Jim

 

[ProspectorPete]

Hi Jim, on the previous 2 trips I've been running with Tracking 'ON' then when I hit a target I switch Tracking off and GB before going over the target again.
This trip I started doing the same but I noticed the Ground Phase not changing in some areas even though the ground had changed. I went back to Tracking OFF and noticed that this would happen over ground where I couldn't do a normal Auto GB so I worked out how to do a manual GB by pushing the trigger forward and pump the coil (as you would for Auto GB) then go either + or - to manually change the numbers while pumping the coil until it was GB'd properly. I had read the user manual when I first got the detector but had forgotten how to do the Manual GB and so far hadn't needed to but on this particular gold field it required me to Manual GB about 40% of the time so it was easier to run with Tracking OFF and go back to GBing every few meters or when I could hear the Threshold becoming unstable and hot rocks starting to 'Boing' a bit more than normal, then I knew it was time to GB again.

Slowly slowly starting to work out signal responses from changes to the conditions a bit quicker now, another 2-3 trips with the detector and I'll feel pretty confident I'll know what I'm doing :lol: , I come away feeling happy if I've learn't something new each trip as I know it will all fall into place very soon and the rewards will be better finds and more confidence in every trip.

 

[Jim.]

Hi Prospecter Pete, I haven't really worried about the ground phase feature. I just like to listen to the threshold, keeping the sensitivity as high as possible in harmony with the Isat setting.
The first time I did a manual ground balance I was listening for the threshold to even out, and it beeped at me letting me see know it was ok ?
Jim

 

[ProspectorPete]

Hi Prospecter Pete,
The first time I did a manual ground balance I was listening for the threshold to even out, and it beeped at me letting me see know it was ok ?
Jim

Hi Jim, when I said Auto GB that was pumping the coil and it beeping at me, on the ground in this field I wasn't able to do that about 40% of the time and that's when I had to manually do the + or - while pumping the coil to get the threshold steady and proper GB, it seemed to relate to very low ground phase and in tracking it wouldn't track on this ground. It was a good thing to happen as it got me thinking about how to overcome it and helped understand the detector better and the interaction with the ground conditions.

 

[OzzieAu]

G'day PP,
Thanks for the video of your efforts with the GR. From observing your methodical approach, I'm sure you will hit paydirt sooner or later with the Makro. Looks like a beaut spot you've got there with your trusty mates for company.
Best of luck and post a vid of that first nuggy.
Adrian.