If you plan to metal detect mostly at former settlement sites that are usually littered with iron nails, their fragments and other small iron debris, be prepared to deal with lots of ambiguous or questionable signals caused by the above-mentioned junk targets. This article covers major types of questionable signals and how to decipher them with the XP Deus.
NOTE 1: The following information is based on a classic setup of tones assigned to ranges of targets: low-pitched tone (audio frequency of 202Hz) is assigned to iron, and a distinct high-pitched tone (any audio frequency above 500Hz) is for desirable targets.
The Deus metal detector incorporates a few useful features - Reactivity, Silencer, Iron Volume and Discrimination, to deal with questionable responses to targets.
However, these features, except Iron Volume (I keep it at 3), if set unreasonably high, can greatly reduce not only a large quantity of the questionable signals of the Iron Falsing and/or Ground Falsing types (described below), but also the Deus' operating depth range. Reduction of the Deus' operating depth range can drastically affect metal detecting results, especially in searching for small hammered coins and medieval artifacts.
Make sure you know how these features work and use them wisely. If you have questions, refer to the following pages in Part I: Reactivity - page 10, Silencer - page 12, Iron Volume - page 9, and Discrimination - page 2.
NOTE 2: Because the Deus is a 'tonal' metal detector, deciphering its questionable responses to targets is mainly based on analyzing audio characteristics of signals. However, a "horseshoe" - Fe/Non-Fe & Depth indicator (see "Profile" on page 19 of Part I), VDI numbers shown on a display, and a Signal Visualization feature (will be described in next article of this Part II soon) may be of some aid to a user.
Below is a list of basic types of questionable signals and descriptions of methods used for deciphering them:
A) Signals of COIN+NAIL Type
NOTE 3: In this article, the term "Coin" refers not only to coins, both low- and high-conductive, but also to small non-ferrous artefacts such as signet rings, fibulae, bracelets, buttons, amulets, etc.
When you receive a questionable signal of the Coin+Nail type, you are likely to hear a "one-way" audio response of a high-pitched tone which is mixed with "iron buzz" of the low-pitched tone assigned to an iron range on a Discrimination scale. The iron range may include both REJECTED and ACCEPTED iron targets. Such a questionable signal CAN NOT be of a "large" size (extended and loud), i.e. remaining strong even after you lift the search coil up a few inches above the target spot.
Depending on the coil's sweep speed and/or a direction from which you approach the target, the high-tone part of the mixed signal may be initially "broken" or even as small as a "click". As soon as you hear the high-tone click, you need to perform some "good signal fishing" (continued on next page).