Red Bars Say you have a shallow iron target close to a deep silver dime. You want to hear the dime and you want to see its VDI. If you are sweeping in the direction such that the iron target gets seen first, you probably won't hear the dime or see the VDI. However, sweeping the other way, your detector sees the dime first, beeps and puts up the +VDI for your dime as well as a green line on the spectragraph.
However, when it goes over the close iron target, the red line from the iron target will be large enough to cause the green line from the dime to drop down into the noise region so you don't see it. You still heard the audio. The VDI from the dime did not get removed because then you wouldn't have the VDI info on the target close to that iron target that was rejected out. If you want to see VDIs from the rejected targets, you can disable visual reject and then you will also see the iron VDIs displayed. But, with visual reject on, only the good VDIs get displayed. Now, noise or inconsistencies in the ground can also generate this, if you are running hot enough. No detector can remove all noise if running hot. You have the choice of running it at lower gains/disc sensitivity if you don't want these false signals or you can run hot and have a much better chance at finding the deeper targets. The reason they don't knock out the +VDI when a stronger iron signal is seen is just so that you have more information to work with. If you want to see more of the spectragraph information, you can lower the base threshold for the spectragraph. It can happen even on non-deep targets. Basically, it's just masking. When you see this, use pinpoint mode to separate the targets, then go back over each one much slower, with shorter strokes. Also turn 90 degrees and sweep the spot. Most likely, you have an iron target next to something good. Rob
