705 Prospecting Mode

[Chris Mac]

Can anyone tell me if my 705 is working correctly in prospecting mode? In prospecting mode the detector reacts to all metals with the iron mask set at 0 and set at 20., unfortunately I have not been able to see how the iron mask works i.e. with the iron mask on full(20) the detector still reacts to a horse shoe and other iron objects . Does the iron mask only mask iron ore in the ground?

 

[Digger]

Iron Mask is a limited form of discrimination, available only in the Prospecting Mode. It should help eliminate small iron targets, but not likely anything near the size of a horseshoe. HH Randy

Here is a short post BarnacleBill made concerning Prospecting Mode, filtering and Iron Mask capabilities.

http://www.findmall.com/read.php?55,1209557,1209876#msg-1209876

 

[David]

I heard it is only for half the depth. Also only for small iron items. The closer to 20 you get you will lose bigger sizes(surface area) of gold.

 

[goldseeker4000]

I do alot of gold hunting with my 705 and I found that the iron mask works well. If the type of metal is ferrus it will blank it out in the middle of the tone. If the target is large it will say overload and give a differen tone. I run mine at around 6 or 7 iron mask setting and found a 1 grain piece of gold. I wanted to see at what point the iron mask would blank it out so i kept raising the mask # until I got to 20 at which point I brushed some dirt over it and swung the coil over it and the 1 grain nugget still rang of loud and true. I was amazed. I tried this with all 6 of my nuggets I found with 705 and I still got strong signals with Iron Mask set on 20. Trust your iron mask. If you get a tone that blanks out in the middle of the signal it is working fine. Every time I dug a blanked out signal it was junk. hope this helps.

 

[Chris Mac]

Thank you everybody for your comments. In prospecting mode my machine makes a humming noise which gets louder when the coil comes into contact with any metal. The mask makes no difference in air tests. Where I feel I have mastered coin and treasure mode; I am not sure if my prospecting mode works properly or if I misunderstand how it is supposed to work.

 

[Digger]

That "humming noise" you referred to is the Threshold tone. In Prospecting mode, the Threshold tone changes in both pitch and volume as the coil scans a target, each of which will vary according to the size and depth of the target. Not the ferrous or conductive properties. There are no TID numbers associated with a target in Prospecting mode. JMHO HH Randy

 

[kirk01]

Have you tried air testing in prospecting mode with iron mask at different levels against very small iron? I will test mine and see what happens.
I usually have it at 0 mask and toggle between it and C&T mode to decide to dig or not.

Interesting comments from goldseeker, hearing small gold with mask at 20!

Good hunting,

Denny

 

[David]

goldseeker, yes, if that is the case then a person should use Iron Mask(IM) set at 20(max) "all of the time" while prospecting for gold nuggets in iron trashy areas. Because a person will not blank out on gold of any size and not much of a risk of losing gold.

In that case a person should try hunting at the beach for jewelry in P Mode at IM 20 for an experiment also.

 

[goldseeker4000]

David, in theoryyou are correct but there are so many annomollies that can happen. For this reason I hunt in 6 or 7 IM and then will ajust up if I have any doubt. It is safer. I hunt up in the mountains and there is alot of trash. Some places I hunt is litterally on the summit of a mountain. the reason for this is the igneus intrusive dikes(granite) push up thru the country rock(limestone) and on the down slopping side you will find nuggets. And it is best to search at the summits because there is little overburden and the nuggets are within detectable depth. A place I hunt, there have been gold nuggets found as big as 9 ozs.