I’ve been getting periodic excessive chatter in the pro zero mode. I will switch over to normal/coin mode and get the bell tone over a target. Switch back to pro mode and then be able to discriminate sound again with more than one target in a small area. Feels like it’s glitching. Any idea what this could be? I’ve tried adjusting sensitivity, ground balancing, and going negative on ground balance.
I have checked my coil connection and I Velcro’d the coil wire to the shaft. I changed batteries last night.
My AT Pro chatter checklist.
1. check connections if I didn't before I started
2. reduce sensitivity one notch or two. Try next step #3 before reducing sensitivity further.
3. Try different frequencies. This has never eliminated strong chatter at full sensitivity, but it sometimes makes it where i can get to one level higher sensitivity on 1 of the frequencies. For example, level 4 sensitivity on frequency 1 while nothing higher than level 3 sensitivity on the other three frequencies. In practical terms the difference is still insignificant.
4. Reduce sensitivity even more. You're not going to miss the typical 2-4 inch coin at 50% or even a bit lower sensitivity, as long as you get your coil over it. The next time you have a clean, solid, coin sized high tone signal stop for a second before you dig and see just how low you can reduce the sensitivity and still get a solid hit. I did this on what turned out to be a silver dime at 4 inches and I still had a solid signal at two bars. With one bar it was still high tone, but clipped. It helped that there was no iron nearby. Still, what matters most for targets under 6 inches is getting your coil over it. Reduced sensitivity can even help when there's iron deeper than a coin.
5. Hard restart. If still getting medium to strong chatter at less than 50% sensitivity then I'll do a hard restart. Hold down the power button for a few seconds until the screen refreshes. You'll lose your settings.
6. Still noisy? Move to a different location to see if it's the detector or EMI.
7. If it's EMI, then deal with it. Go to 1 bar sensitivity and increase it as much as I can and still pick out a good, repeatable signal.
9 If it's the detector and persists, call Garrett.