Hotrocks and the SDC 2300

[Moneybox]

I don't know anything about your Minelab machines because the ATX is my first detector. I complained to the dealer that I way having problems with chatter.
The book shows doing a Frequency Scan in initial setup with the coil held vertical. He said when we are in the highly mineralised areas the signals we're trying to iliminate are coming from the ground. The best way to do a frequency scan on the ATX is with the coil flat on the ground.
I've found these difficult hot rocks usually congregate together. I do a fresh frequency scan with the coil flat on the hot rocks. Then do another ground balance over them as well. Most times it gets rid of all the chatter but I can't completly remove the worst of the hot rocks. They are just another chunk of metal. The light coloured light ones are a mystery though. Some of them seem to be the worst and they don't stick to the magnet.
I've thought of taking them home and crushing them but I'm a little too busy or lazy to do that.

 

[old hand]

I don't know much about the ATX but the chatter is more than likely to be EMI as you said using the tune button reduces that with the ML I just put the detector on the ground and hit the button. Hot rods in some areas are worse than others by ground balancing you should be able to eliminated them if not try backing the gain off or another coil ,its important to have the detector running stable a constant a smooth threshold regards john

 

[stalker]

The atx doesn't suffer from emi using the dd coil it's very well shielded ... It's the ground that It's on. It's very sensitive to basalt and hot rocks . If your not using the ground track you'll be ground balancing alot more as it drifts out of tune. . if your sensitivity is to high it will chatter also . Try one of the 3 ground track modes and do a ground balance after you've selected one. . See If that settles it down .

 

[Moneybox]

Tanks for that I've never tried auto tracking because I've been told it reduces sensitivity. I'll give it a go next time I'm on difficult ground. I'm west of Broken Hill now heading west so will be looking for somewhere in SA to try my luck on the way through.

 

[Nanjim]

Moneybox

Safe travels ...
Look forward to trip report....
Return to the west .....

Cheers Nanjim
Jim

 

[RedDirtDigger]

I often detect in deep leads (river gravels shedding from under basalt flows that flowed down gold bearing creek valleys covering the gold in 2-100 metres of basalt). The Tertiary aged basalts 40-10 million years old that are common along the great divide decompose producing many rounded boulders high in iron. The Minelab dedicated gold machines including the SDC cannot overcome the basalt cobbles and the sweet signals they give off. Every second cobble is decomposed to a point where the iron gives a beautiful sounding signal response. I look for gaps between the cobbles or bare/shallow bedrock situations or where the basalt has been removed to find the deep lead gold among the basalt cobbles. You can pick out some shallow gold signals from the cobbles due to the signal being very strong and sharp occassionally

RDD.

PS i have not tried a vlf-discriminating machine on them but would still prefer looking for the gold with the 4500 in spots where there are less or no baslat cobbles.

 

[Heatho]

Great info RDD, thanks, much appreciate your input.