I won't be wrapping my F75 around a tree after all.

[JOHND84094]

In an earlier post I had written that I thought that I might have had a bad F75. It looks like it was just the dip stick trying to use it. Thanks for your messages and suggestions. I'm a newbie to metal detecting. My F75 was going a little crazy before, but I think it just must have been how I had it set up. I tightened the knurled nut from the coil wire where it goes into the back of the display housing another three quarters turn. I also tried a few of the other things that you guys suggested. It seems to be running quite a bit better now. I still get quite a few false signals up in the 90s though that don't repeat over where I heard them. Usually when I go back over where I got the 90s blip, there is no reading. I'm not sure why it does that. Is that normal?

I went out on my front lawn after work tonight and tried it out again. I dug six coins all out of the same eight inch plug! Then I dug another ten coins. I located another couple of pennies, but the hole in my lawn was worth a lot more than a penny each. I didn't get anything great, like you guys are finding. Just modern clad, but it was better than a kick in the butt. Things are looking better. I was getting a bit discouraged. I have a long way to go though. This is a lot of fun.

Thanks again for all of your suggestions and help. There are a pretty good bunch of guys on this Fisher F75 Forum.

HH, John

 

[MattR]

Well done John.

High 90's can be caused by relatively 'large' iron targets. (Larger than a coin). Often it is a damp, rusty item.

It helps to also observe you're confidence graph and depth bar when such high numbers appear.
'Deep' indications and 'low confidence' often are the clues to 'big' iron. (Which fools many detectors).

A good target of 90 'value' would give well defined indications of depth and confidence of similar levels.

Checking such targets with the pin-point function should expose the size of the offending ferrous item. Just be aware NOT to artificially reduce such a target's apparent size by triggering over the item. ('Ratcheting down')

In trashy areas keep your sense around 60 and don't use Je.
There is no point in trying to force your F75 through heavy trash.
Instead, try standing still and delicately scan the area about you.
You will be surprised what you can wheedle out. Develop the skill and patience required for tough spots. Don't think that you have to stride all over the place to be successful.

When you find a productive spot, work it until you are confident that you have done your best.

Finally, remember to scan a difficult target from at least two directions. (at 90 degrees to each other).
Dig a few of these to learn what produces the types of response you will experience. It's the only way to learn ........Good luck........MattR.UK.

 

[jim tn]

John, first off, welcome to a very wonderful hobby. It has saved my sanity now for over 30 years. Although some might question that statement. Matt has covered many of the important aspects of the f75. It sounds to me like it is now just a matter of time afield for you. For the first few trips out with the f75, I would suggest spots that contain less trash. Hit a few of the tot lots and school yards. That way you will have a chance to hear the various tones and note the readings easier. And, don't be afaird to dig some trash. Each piece will be a learning process. Small target 90's readings for me usualy result in a rusty bottlecap. Again, welcome and HH. jim tn

 

[Bill Ladd]

as I said before...the F75 is so sensitive it's hard for even the most experienced detectorists to master. As a beginner you will have an even tougher time. But just keep taking it slow & try to have fun with it & you'll be fine.....
HH,
Bill

 

[Mark in NC]

The F-75 is very "usable" right out of the box, but thankfully, it has enough deep down complexity that it will take months/years to master. Keep working with yours, and you'll find it keeps getting better and better! Like Bill said, keep asking those questions! I promise you, you aren't the only one wanting to know the answers, as a lot of folks are just too shy to ask. Everyone on this forum are learning together, as this is a very new machine... definitely a "group effort".

 

[Tagamet]

I just wanted to say thanks for your informative posts. I always learn a lot from them (and I've been hunting since Hector was a pup).
Thanks again,
Tagamet

 

[Richard@BackwoodsDetectors]

The F-75 is hotter than any other machine you'll use...take it easy on the sensitivity and the use of multiple tones.. Run the sensitivity at 40 or lower to get it to run quieter...3 is good on the audio...have fun...Richard

Authorized Fisher Dealer

 

[JOHND84094]

what I was referring to on the 90 plus ID readings on the display accompanied by the high tones. Quite often as I am sweeping smoothly back and forth, keeping a consistent hight and speed, I'll get a quick bleep high tone along with a high ID number. It's not a real strong signal like hitting a coin a couple of inches down. I'll go back over where I got the reading and hit it from all angles and there isn't anything there. It's like a false signal. Is this normal? Again my ground reads upper 80s. I ground balance, use 5 or 10 discrimination, keep the sensitivity down, De process, Fe .01 to .03 and I like 3H tones best.

HH, John

 

[Jackpine Savage]

That is the occasional false signal all detectors give off the edge of some iron targets. With the disc at 5 you should be able to hear the iron low tone from the offending target.

Tom

 

[Tagamet]

[quote JOHND84094]what I was referring to on the 90 plus ID readings on the display accompanied by the high tones. Quite often as I am sweeping smoothly back and forth, keeping a consistent hight and speed, I'll get a quick bleep high tone along with a high ID number. It's not a real strong signal like hitting a coin a couple of inches down. I'll go back over where I got the reading and hit it from all angles and there isn't anything there. It's like a false signal. Is this normal? Again my ground reads upper 80s. I ground balance, use 5 or 10 discrimination, keep the sensitivity down, De process, Fe .01 to .03 and I like 3H tones best.
HH, John[/quote]

Mine often behaves this way at one site (an old iron furnace) that has (literally) tons of "hot rocks" - rocks that sound off as targets because of high iron content. I've tried all of my machines there and they all "misbehave". The one thing that doesn't fit the hot rock theory is that this site's hot rock's signals are repeatable. I can dig up a few rocks and lay them on the ground and rescan them to find the individual rocks that caused the signal. Can you find a site where the F75 balances in the 50's or 60's? My best "learning site" is a set of soccer fields where they imported the topsoil and there is minimal trash and maximun clad. I take ALL my "new" machines there to learn how to use them. THEN I go to more challenging sites.
The good news is that you bought a great machine that wasn't even available a few months ago. The bad news is that (like all good machines), it takes some time to learn how to use it. Some of us have a bit more mileage on the experience odometer, and that's a big help. But we ALL use this forum to continue our climb of the learning curve. You should too!
Tagamet
PS I'm about to answer your PM.