CZ-3D + iron falsing.

My father has just got hold of a CZ-3D, a detector that he has always fancied trying out. I have had one before and I mentioned to him about it's tendency to false on some iron.

He has been out today with it and has found the same thing. Quite a lot of the time, the CZ-3D tends to false to a high tone on iron - this can make it quite annoying to use.
Sensitivity was not too high - he tried varying amounts between 3.5 and 4.5. Discrim was set on zero and volume on 5.

Anybody got any ideas how to get around this problem?

For now...... dig the repeatable 4-way hi-tones. Then graduate to the 3-way hi-tones. Nails have always been serious problems for many detectors..... especially the hi-powered units (high Sens.). After a while, you will find yourself recovering somewhat repeatable 2-way signals.

Tom