White’s Electronics MX5 - Manual (Page 18)

Page 18
MX5
Owner’s Manual
Misc Tips
Sensitivity (again)
There is a strong desire to always run a detector at maxi-
mum sensitivity. However, this not only increases the response
to target signals, but also that of ground signals and electromag-
netic interference (EMI). A common mistake is to assume that
higher sensitivity will always give better depth. In air tests this
is generally true, but ground results can depend on the amount
and type of mineralization. The maximum level is usually only
useful in the very quietest locations, and for most hunting you
will probably need to use a lower setting. In general, set the sen-
sitivity as high as possible to get a smooth, chatter-free thresh-
old audio, but no higher.
Bottle caps
Steel bottle caps are a little different than most iron targets
as they have both a magnetic response and an eddy current
response. As such, the composite response can appear either
ferrous or non-ferrous, and the response further depends on the
type of loop being used. With a DD loop bottle caps often look
like a US quarter, and with a concentric they often look like a
US nickel. However, they tend to give an inconsistent audio
response as sweep speed is varied. The audio often rolls
between ferrous and non-ferrous. This is easier to distinguish in
multi-tone modes and with some practice you will learn how to
recognize the audio responses of most bottle caps.
Coil Size
With any metal detector, the size of the search coil presents
a trade-off between depth and sensitivity. A larger coil offers
better depth on larger targets at the expense of small-target sen-
sitivity, and a smaller coil has better sensitivity to small targets,
but at a lesser depth. A small coils also does a better job of sep-
arating targets when hunting in trashy areas.