Hello JHM, I found it interesting that you mentioned the Quattro will pick up a coin at the same time the threshold is nulling over a target. The nulling over a target must be a discriminated target. So you may be using some discrimination, hence the nulling happens over targets which have been discriminated against only. So if there is another target OTHER than the discriminated ones, you should pick them up, whether it be a coin or relic. There's nothing unusual about that. When we speak of "slow recovery time", what we're referring to is the time the computer takes to reset itself from one target to another, when both targets are in very close proximity to each other. You may have two coins for instance, an inch apart, and the detector picks up the first, but not the second. This is where the slower the coil sweep, the better. This gives the computer that second or two needed to reset, in order to read the 2nd coin. But this isn't always the case. In competition hunting, where you're expected to find as many targets in a given time, as is possible, is why the Quattro may not be suited for this type of hunting, especially if the targets are buried in very close proximity to each other. But this wouldn't always be the case, so the detector could work for you here too. Another senario: say your detecting in iron infested ground, or really trashy ground where a mixture of different metals have over time, impregnated the ground with traces from the metals. Your detector is trying to read through all that, for any keepers in the ground, and tell you where those keepers are. This could cause the computer to lose time in "recovering" or time speed, while reading the ground conditions.
So, yes, you can pick up targets, while nulling over discriminated items. This is discrimination at work. The recovery time factor is different again, as I've briefly explained,without going to much into it. Maybe someone else would like to offer a further explanation.
Cheers Golden

