ultimate coil and iron

[david995]

most likely you will be missing a lot of targets with the sensitivity set so high as the machine will be nulling out a lot , that would be the case on most of my ground

[carling2]

all machines null out to certain degree on any site and the more action a site sees or the older it is the more they null out ,,I always find having your sensitivity up high makes the tiny deep signals that much easier to pick up,,,i prefer my machine nulling out as if you know your sites you can work out where the most activity was.

[david995]

on some of the highly minerllised groiund i detect on at 29 the se would be nulled out all the time,  so would only pick up  a signal on the most obvious of targets

[carling2]

that's crazy,, only once I had to knock me sensitivity down and that's because the field was full of coke,,as for this obvious target business ,, we must have special dirt in Herefordshire 

[Chef Geoff]

 ???No Paul when it's nulling it's not detecting and if I remember correctly you run with far more disc on your screen than most so you'll be detecting even less, but of course there could be something wrong with yours as mine and most never have a problem with coke
As I said before David detecting with an open screen is your answer, there are no easy outs either put up with the noise or lower the sens/audio gain or you could fool yourself and buy a machine that hasn't got a threshold and hasn't got the sensitivity in the first place

[david995]

I know,  but if i go the beach i can ramp it up to 30 - 32 no problem   to get a decent hum / thresh thold im down to 17-20 geoff was saying on some land he detects on its down to 9 !  but you need that contstant hum or you do miss stuff   you must have some great ground , i do hav esome farms where 25 - 27 if fine

[carling2]

I must be a rubbish tectorist then ,, oh well back to the painting ,, I always thought nulling was when you was going over iron

[david995]

nulling is when you go over anything you have descriminated out , but when its nulling you are not detecting the good stuff

[david995]

geoff what would be your coil and size of coil of choice for mineralised ground ?   and running in all metal , i usually run in cinductive , would you switch to ferrous for ease on the ears ?

[Chef Geoff]

Paul is right in saying that nullling is a sign of iron not normal mineralisation but if you have like iron ore or pyrites then it will null, I use the Minelab rule of thumb in that the more iron you have the less disc you can use, yes this can make your ears bleed yes ferrous can be a little less painful on your ears than conductive but the machine isn't going to do it all for you and a little suffering is good for the soul
The Minelab 7.5", coilteck joey 5"X 10" or Detech 8"X 6" SEF would be my choice when stepping down in size.
If you have a lot of land with this problem then I would probably look at getting a second machine, probably a Tesoro or Laser as they are very good around iron and won't burn too big a hole in your wallet

[david995]

the ground is a red colour on the worst farms,  so as you say is proberbly  iron but anyway its nulling the machine out whatever it is   what is it that makes the tesoro etc better on ground with iron ?

[carling2]

I know what the screen looks like on me kit ,, but I don't bother looking at it,, all I do is run in iron mask {about 21-22} and dig everything that sounds half decent.

[Chef Geoff]

That's what I mean with IM 21-22 I'm surprised you find anything far too much discrimination for any iffy signals

[carling2]

your kit must be faulty 

[david995]

I dont think so,  its fine on the beach right up to max sensitivity   , its  just in red soil a problem   i see in andy sabasch book most are reconmending sensivity around 17 - 20