Re: I don't care what anyone says.,it's not the easiest detector to use because it wall latch onto ferrous items .........????...MattR.UK

[MattR]

QUOTE:---Its not the easiest detector to use because it wall latch onto ferrous items

Hi J

Not sure that I see what exactly you imply by that.....Are you saying it acts differently to iron more so than any other detector?

ALL detectors behave towards iron with the same 'passion'. ( pro rata their frequency of operation) Iron is hundreds of times more 'attractive' than any none magnetic material, so what do you feel is different about the F75 compared to whatever other unit you may be thinking of?

As a matter of fact, the F75/T2 will 'de-latch' themselves from iron that much sooner than the average unit, because of its intrinsic design features of being a 'fast' detector.

Do you simply mean it is more sensitive to smaller bits?

If so, then that's simply the fact of being designed so, to do the job .

Whatever J....You are certainly taming the Tiger in the F75.

Why not set your disc to 10, and audio to 1F, process JE, and sensitivity to the local Ether noise.

You shouldn't hear much iron, and yet you will be up there with the 'big-dreadnoughts.... 'Minelayers'........ but cruising faster and creating less waves.

Try an experiment....forget numbers......dig by '1F sweet, repeatable, both-way' sounds'........you will find more.





..............Well done, and good hunting............MattR.UK

 

[cspene]

n/t

 

[Streak!]

1f is simply too time consuming, and besides, I LIKE to hear all the rusty nails and such. Tells me I'm getting into a "busy" area, and therefore a productive area. I also run my disc at 6, and usually choose JE mode. I DONT choose a slightly more positive GB, as it does no good at all, except it "may" make the 75 a tad quieter in certain area. A spot on GB will be more sensitive and deeper. I found I dont lose much at all using 2F over 1F (tried both extensively in the same area, one after the other). I can dig more just by listening to the machine than I can having to check the display for every signal. I just dig everything that give me a "reasonable" high tone. if you run 2f, and accept down to 6, your only digging from around 14-15 in the disc scale up anyway, and I've never ever dug one good target below maybe 18, and very very few of them.
The F75 sounds off on iron with the best of them, but its REAL strength is its lightning fast recovery-reset speed. It will recover and be able to pick up the next target far faster than most, and therefore is fantastic in heavy iron.............much better than any machine I've ever used (and I've used a few)
I've never heard the term De-latch to describe recovery speed before Matt. must be a British thing!

 

[MattR]

Hello Streak, and thanks for the post.

I reply to each section appropriately:-


1F is simply too time consuming, and besides, I LIKE to hear all the rusty nails and such. Tells me I'm getting into a "busy" area, and therefore a productive area. I also run my disc at 6, and usually choose JE mode.

Streak

 

[Streak!]

I've long enjoyed your posts, as they usually have a technical aspect lacking in most. I envy your background, as it surely opens a few windows of understanding for you that a great many of us don't get the benefit of. Seem we tend to agree more than we disagree.While I DO have a pretty good understanding of basic VLF theory and the fundamentals of how detectors work, I cant go toe to toe with you in the More technical aspects of it, so go easy on me!!!
One little thing though, that I have to take issue with..

Thats is........the assertion by me that a slightly positive bias on the GB will result in quieter operation.(and your subsequent assertion that thats incorrect). While on paper it may seem the opposite, quite the reverse is true. (bear with me here) Logic tell us that a positive setting increases the machines sensitivity to the ground, and thats exactly right. Turn your GB more positive, and you'll be able to pick the ground up further off the ground, where as if your GB is spot on, there should be no reaction from the ground at all. (everything else being equal) This SHOULD result in noisier operation.................but when applied in small doses, actually does the opposite. I don't have the technical knowledge to even try to presume I know exactly whats happening, but know from experience what the results are in the real world.
Case in point. I've been a long time user of shadows, specifically the Shadow X5. When the 5 was first released, a common complaint was that is was too chattery (MUCH like the initial complaints about the F75). It was determined almost right away that to tame it down a bit, one was required to, after achieving a neutral GB setting....to turn the GB know as much as a half turn positive! (this is with a 10 turn GB pot). It worked swimmingly, and produced a machine that was far easier on the ears. Also, on machines that come with a fixed GB, you'll find that most of them come with an even more positively biased GB, to make the machine a bit more user friendly and operate in a wider range of conditions.
I recently have the pleasure of hunting in one of those infamous "hot spots" in Va, where the dirt was as red as the surface of mars.(VERY high FE content) You HAD to hunt in all metal, as the target responses in DISC were poor at best, and only resulted in shallow recoveries (if any recoveries were to be had at all). In short, all metal hunting was a MUST. Oddly enough, it only took a little while to get the feel for all metal hunting, and it was easy to keep the GB on, (despite the fact the ground changed every 10 feet!!) because as you swung the coil, you could actually hear the ground change as you went along. If your GB drifted a bit negative, it got real chattery...........if it drifted positive, it got quieter, but you got a waaaaaaa...waaaaaaa at the end of each swing. (the result of unconsciously raising the coil off the ground a bit at the terminus of the swing). Also, it was pretty easy to get the "feel" for what the target was, despite the fact you were in all metal and had no Target ID at all.

OK, I'm getting to the point here. I think what is actually happening when one chooses a slightly (emphasis on slight) positive GB over a more neutral one, is that at a more positive setting, more very low tiny conductive targets (precisely the targets that produce the bulk of the chattery noise we complain about when using a sensitive machine) get "blended into the ground signal, and we don't hear most of them anymore. Thats my best guess anyway. I'm anxious to hear your take on this Matt.
On another note, my earlier comments on the type of soil in the west in the UK were based on a few posts I've read over the years from UK based detectorists. In retrospect however, I seem to remembers that most of those posts were complaining about the sheer iron content of the ground, not in mineralization, but iron debris, and most said it was far worse in the west than the east. My Bad! I HAVE detected a fair amount in a number of areas in Norfolk, and don't remember encountering and areas with extreme mineralization, BUT, I suspect that my opinion on that may be biased due to the fact I may have been comparing it to what we consider extreme over here, and by comparison, the UK HAS no extreme areas!! We have sites here Matt, where the mineralization is soo severe you can lay a good target right on top of the ground and cant pick it up with a top of the line machine!!! (in Disc that is). ON TOP OF THE GROUND!!!!!!

anyway, enjoyed your post. Now have at it mate!! Streak!

(PS: I think I'm going to have the opportunity to hunt soon in one of those "hot spots" with the F75 to see how well IT works in severe Fe mineralization. I'm anxious to see how well the ID works in all metal in sites like this, and to see the depth capabilities of the F75 in really really hot soil. )

 

[Scully]

I agree with you Streak. I have been using the F75 now for about 4 months now, and still feel that I am learning but I do see an improvement when setting the GB slightly positive. It does quiet the machine down some and knocks out the really tiny targets that can be a pain. This machine is very sensitive and I know for a fact its helps me avoid those tiny targets but I also have to beleive that it can do the same on small "pockets" of mineralization. There are "pockets" of mineraliztion in some of the areas I hunt, that virtually disappear after you disturb the soil, and I hate those more than the small nails. On very old sites where I want max depth I run disc down to 4 and watch the id numbers, JE mode, 2 tone. An target in dual digits gets investigated.