Couldn't manually Ground Balance

[Roland58]

Went to a very old park today. It has been quite dry here for a while. The soil in the park is iron ore (red) clay and it was hard as concrete. I was using AM motion mode, but, could not GB! From 0 - 99 I got a negative indication.....like pulling a tone out of the ground, got a tone on the up stroke of pumping the coil. I tried reducing sensitivity and setting threshold in the negative, to no avail. I like to run with a ground balance slightly positive......slight tone when lowering the coil during the pumping.

There was a little EMI when I first entered the park, from power lines running along the road in front, but, even after getting away from the EMI, I was still unable to ground balance. Has anyone run into this? and what is the solution??


Edit: Should have mentioned that I went to another part this evening and all was well.....ground balance was set, cranked up the sens, set threshold back in the positive.

 

[tvr]

Maybe not the same thing I found .. but this past week got a short hunt in mid-week. Was going fine, then could not ground balance. Switched to all metal and could not ground balance. Same as you, would sound off on the up stroke, even when GB was at 99. I reset the detector to the factory default, and still could not ground balance. Was going to take the batteries out and when flipping the detector over noticed the coil connector was a bit loose. Tightened the connector good and snug and was back in business. Ground balanced fine. Could then also run the sensitivity up a little higher than I was at before the ground balance went wacky.

 

[Roland58]

Good thing to check, however, that was not my case. I think, if it happens again, I'm going to try changing the frequency to see if that might help. I was still getting my signals, they were just mixed in with the noise.

 

[Greg (E.Tn)]

Two different situations where I had trouble with GB was (1.) where I had my sensitivity set too high, and (2.) where there was cellphone interference.

 

[Elton]

n/t

 

[jim tn]

I don't carry a cell phone afield, but like Greg, at times to high of a sen. setting has caused me GB problems. HH jim tn

 

[martinfabio]

its happen to me a few times on the f70 turning off and on sometimes correct it but when that dont work i carry on detecting and after 10 mins or so then it will gb but same as you all
the connectors are on properly. its happened about 5 times over the year so i dont really worry about it now.