F70 + 5" DD Bed of Nails Hunting Strategy :detecting:

[Cal_Cobra]

Heading up North next weekend and am planning to put the F70 with the new little 5" DD to the ultimate test in an old Victorian era resort that's covered with old square nails.

I saw a post where the guy (sorry I forgot who posted it) was using the F75 (same thing practically) and had set his sensitivity to 10....yep TEN, and his threshold was maxed out as I recall, and he did pretty well with those settings. What do you guys think?

A giant electromagnet would be nice to bring

 

[WTnFred]

Cal,

I tried this with my F70 and found a 1903 IH next to a large nail about three inches deep. I had already hit this site with my F75 and the DD coil. I think less sensitivity produces a smaller foot print, which equals better discrimination. I will only reduce the sensitivity after I have hammered a site with my normal settings (3, 70, 3H).

I don't know how we can adjust the threshold with the F75 in disc mode or if it is even needed. My F75 was being upgraded and repaired so I haven't had a chance to try it with low sensitivity but it did seemed to work with the F70.

HH
Fred

 

[Cal_Cobra]

Hey Fred,

That was a nice find, so I'd say it's a good setup to try. I'm trying to wrap my mind around this running in monotone business like Nasa Tom suggests, although it's a little different scenario on the F70 vs F75, as Tom reports that the F75 "the moment you invoke a different tone option; Say 2-tone, 3-tone, 4-tone, etc.... the Disc, ....even though it's set on '6'...... will instantly become a Disc setting of '15'."

Can anyone confirm if the F75 actually shows it's running a disc setting of '15' after making the tone change, or is he privy to some internal programming information from Fisher, even though the machine may well say it's running disc 6 ?

I frequently run the F70 with the disc set to 6, but in 3H tones, but have never seen the tone setting affect the disc setting.

hh,
Brian

 

[gates21]

That was Merf that posted that. We hunt a lot in fields that have a bed of old square nails and just a few non-ferrous targets mixed in. It definitely sounds different having the thresh up that high, but you can still pick out the good targets amongst the trash. A good target sounds like one of the old dot matrix printers.