Fisher F75se ground balancing

[ramer]

I am having a very difficult time with the fast track ground balancing. Not sure what I'm doing wrong. I only have about 10 hours on this machne so I am super new with it.
Anyhow, 9 times out of 10 or maybe 19 times out of 20 when I try the fast track it says "Can't GB." I've tried various settings mostly with the same results. The Fe graph reads .03.
I've never seen it go lower than 70 when fast tracking it. Usually it starts out there and climbs to 99 and then says it can't gb. Maybe something is wrong with the coil. It is the stock coil that I use.
I do know that it chatters so much that maybe I can't determine if I am over a clean piece of ground. I have the disc level set to 8 and the sensitivity set to 60 or less and I am in the default process "dE." I have been using it in the woods, as well as 4 different parks.
Have there been any coil issues that anyone has heard about with the F75?
Thanks for any help.

 

[Elton]

Are you holding the switch forward and bobbing the coil 3" to about 12 up from the ground.. Is the ground clear of items..... It only has fast grab.. No fast tracking on the F75..
In other words it stays at the Gb you set it by bobbing.. It does not track to the ground.. as you hunt..

 

[pasttom]

My biggest problem is finding a patch of dirt that is without metal to GB. The 11 inch coil is almost impossible to find a clean spot. If I use the 5 incher and also Boost process I don't have too much problem. I find this combination much easier to use all around.
Tom

 

[ramer]

Sorry, yes, I meant to say Fast Grab, not Fast Trac.
So there have been issues with some of these stock F75 coils? I wonder if Fisher would identify my coil SN as one that is possibly defective. I bought it used so I'm not sure what the warranty situation is.
And you suggest pumping the coil from 3" to 12". Ok, I'll try that too. The manual says pump it from 1" to 6". But at this point I'll try anything that works. Would turning down the sensitivity to a very low number help and would setting the disc level to 0 also help while using the Fast Grab procedure.

 

[Dave J.]

Ramer, what you've described so far sounds like a combination of three things: weak mineralization, electrical interference, and inexperience in doing Ground Grab, and possibly metal targets in the ground you aren't aware of, all conspiring to cause the machine to say "I can't ground balance here!"

If the machine is working properly, but the conditions do not afford signals suitable for ground balancing, the best thing to do is to turn it off and then back on to force a reset to the default ground balance setting which as I recall is about 90 (sorry, don't have the data in front of me at the moment).

The circuitry and software that's involved in "Ground Grab" doesn't care how you have controls set, as long as the sensitivity is above 30.

* * * * * *

There's probably nothing wrong with your machine. I'll butt out for a while to see if you and the other forum denizen experts get the thing worked out, chances are y'all will. I'll check the thread now and then and if I come to the conclusion that your machine has something wrong with it, I'll intervene.

--Dave J. (Chief Designer at Fisher)

 

[NE Digger]

n/t

 

[ramer]

Thanks to all who replied. Dave J., I didn't realize that the sensitivity had to be above 30 to properly "ground grab." There is nothing in the manual regarding this. I'll make sure it is above 30. Pretty sure it has been because on several occasions I reset it back to factory settings which brings the sensitivity to 60. Also what about the disc settings. Where should that be or doesn't it make any difference at all? I know one thing that I haven't been doing correctly after reading the manual for the umpteenth time last night. It says after you are certain there is no metal where you will do the ground grab, raise the coil over a foot into the air before beginning the ground grab and then pump the coil from 1" to 6" several times a second. I haven't been raising the coil far enough off the ground before ground balancing. Maybe that is the problem.
If it stops raining I'll be out there again today following every's advice.

Thanks again

 

[Elton]

Where the coil wire connects to the Meter Head... Please make sure it is screwed all the way on. Even though it seems it is..Sometimes ( Often) even, it isn't tightened down all the way.

This issue will cause some problems with proper operation... I also noticed where there are many items in the ground, and you can't get a clean ground balance the preset 90 works swell in those areas.......... Though per your statement your hunting in the woods, Unless it was a dumping ground and it displays can't GB It may be some outside interference........... Has it ever GB properly ?? In any other area?? I would say Call Felix at FT.... He will help you, and if it has to be, send it in now.... Frustration levels will continue to grow if you keep having problems. The F75 is a fine piece of equipment and well worth having it checked out. We can Arm Chair coach you all day..but , only you know what is going on where your at detecting.

Now that said, GB is always best........... But if you can't for some reason, EMI, Mineralisation the preset will work.. Again, Sir..not saying ignore the problem and hunt..just that if you can't Gb. Preset will work for that instance if your in discrimination mode. It will not work in all metal mode....


It is also possible in some soil..every time you GB you will get a different reading.. so in essence it is a good thing to fast grab often.. Of course that is only if you get a Ground Balance, Can't Gb is
just that..No Ground Balance being set on the machine..

 

[pasttom]

Ramer, you mentioned that you'd make sure you were above 30 sens to GB. Why would you ever get near there or stay there? The worst conditions I've seen I didn't go below 40 with the exception of beach hunting where things go crazy low and you have to Manual Balance. If you are hunting at that low degree of sens you are missing a lot of targets. I know sometimes less is more and the F75 will hunt better at low sens that most or maybe all other machines, but... I try to get the highest setting that is stable. Anyway, unless you are beach hunting, fighting EXTREME EMI or getting signal reflection from all higher settings, I don't know why you'd ever go near sens 30.
just sayin...
PastTom

 

[EtracTom-AdirondacksNY]

I had to re read the manual too a couple of times. I set the machine to sensitivity 99 all the way up first . Then I pushed the trigger forewards and did the ground grab ballancing mine was like 85-87 so I read to set it up a few numbers 3-5 higher to help with ground noise due to mineralization and hot rocks while sweeping so I set it to 90 and I think I will leave it there till I go to a different area and see what it reads at. Then go to discrimination and set it to zero and then BP mode or BOOST MODE then pushdown the menu button and push the trigger forewards once each time to see what F1 - F7 channel it's on and roll through them all and listen for several seconds to each one to find the one with the least or no EMI with the coil parallel to and about a foot off the ground. Mine was quiet at F4 the factory setting but had noise on the others. Then it was very noisy so I lowered senitivity down to 87 and that is when the machine quited down some while just holding it still with coil near or on the ground. BUT I still got a very chattery machine while using it so I had to go down finally to 30 sensitivity and I am in the BP or BOOST MODE and with zero discrimination it is in a higher GAIN setting due to the low discrimination. Discrimination 1-5 are a higher gain mode on this machine and there is a good jump from 5 down to 4 on down in the gain. So that is reason to run ZERO discrimination is it helps eliminate the masking of targets so it will read them all leaving YOU to do the discrimination and it's in the highest GAIN setting. Ran excellent for me last night my second time using it. If the conditions allow I will crank the SENSITIVITY up more but leave DISCRIMINATION in ZERO and run in BOOST MODE ALL THE TIME if possiable as it runs hotter and goes deeper and hits better with better ID on the machine according to any and all things I have read from Tom Dankowski and the SENSITIVITY setting don't matter very much due to running it in that BP BOOST MODE. ZERO DISCRIMINATION will allow it to see all in the ground and YOU can discriminate and not miss co located items due to tash and iron. Last night I got a bouncy iron foil and nickel reading ID around 20 something and it was foil and a old nicken all rusty and some green corrosion on it so it works. I ran it up to 40 and 50 Sensitivity but was very chatty while sweeping and made me doubt myself if I was missing a target weak hit so 30 sensitivity at this wet field was pretty quiet so it worked for me.

 

[ramer]

Uh yeah, pastom, one of the posters said to make sure my sensitivity was above 30 before I did the ground grab so that's why I posted that. Typically I would rather run it as hot as it can go until the chatter is intolerable.
In any case, I was out again today for 5 hours, in the woods and in parks. It just does not ground grab or maybe it will one time out of 20 attempts. It usally starts out higher than 90 and goes to 99 and then says "can't gb." The numbers have NEVER gone below 90 in any ground grab attempts. I am almost certain now that the control box is bad or the coil is bad. I will try the 5 inch coil tomorrow and if that works then maybe the stock coil is defective. Another poster did mention that there had been issues with these F75se coils in the past.
I won't be using this F75 again until I can get together with a friend of mine who has an identical machine and has a few years experience on his. If he can't do a normal ground grab with my machine then it is bad and hopefully Fisher can fix it. Learning a complex machine is difficult enough but if you suspect it is defective, then you will never be able to learn it.
I've had it for now, almost 20 hours hunting with it and still having the same problem. Enough frustration already. I'll be back to using my xterra 50 until this matter is settled. And I love that machine anyhow.

Thanks for everyone's help and suggestions.

 

[NE Digger]

I'm tellin ya, it has to be 100% tight. check it................. Also.....................are you able to manually ground balance it?

 

[pasttom]

I think some really basic videos would help immensely where we could watch an expert go over basic steps and we could hear and see proper GB etc.
If the 5 inch coil does not work MUCH better, then I guess you do have a defect that needs to be looked at in El Paso.
Tom

 

[Dave J.]

It probably doesn't say this in the manual, but when ever you change the frequency, you should follow that with another ground balance maneuver since changing the frequency shifts the ground balance point slightly. Under most conditions in disc mode the shift would not be noticeable, but in many conditions you'd notice it in all metals mode.

Also, it's possible to ground balance at a sensitivity setting below 30, but you may see a slightly different setting. Sorry my previous remark led to some confusion about that.

--Dave J.

 

[tvr]

I have to agree with the repeated comments about making sure the coil connector is tight (finger tight). I've had multiple occasions of the beast not acting normal and not ground grabbing. After re-tightening the coil connector, it was just fine. Sometimes a sequence of loosen it, wiggle the connector part to make sure it is seated then tightening the collar would work wonders. Would most frequently happen after changing coils and using for a little while.
Cheers,
tvr

 

[Elton]

I think some really basic videos would help immensely where we could watch an expert go over basic steps and we could hear and see proper GB etc.
If the 5 inch coil does not work MUCH better, then I guess you do have a defect that needs to be looked at in El Paso.
Tom

Try this Link.click on F75 video Manual..................................http://www.fisherlab.com/hobby/video.htm 4th video down on left Watch it all It covers Ground Balance

 

[ramer]

I watched the video several times on Youtube and it comes in 3 videos. Your link has all 3 videos linked together as one video. Good video but when the guy demonstrated the fast grab he said to make sure there was no metal where you did the fast grab. He then ground balances it and runs it on the ground and detects metal EXACTLY where he did the fast grab. He ground balances it a second time right over the same spot and right over the metal in the ground he just detected and gets exactly the same ground balance reading. This part of the video starts at 6:39. Something is not right here. I can't ground balance over metal free ground and he is doing it just fine over ground with metal right under the coil. That part of the video the guy really screwed up. Does exactly the opposite of what he tells you not to do.
Again, thanks for all the help and suggestions and comments. I'll let my friend take a look at this detector. He is an expert on the F75se.

 

[WV62]

About all I can say is ground balancing (fast grab) is not that hard to do, I can't remember ever having mine to not GB. So for sure I would say you got some kind of a problem.

 

[EtracTom-AdirondacksNY]

Are you pushing the trigger forewards for GBing?? Maybe your ground is less than 40 GB like on a beach or sandy areas so you will have to manual GB the detector in that case. If all else fails just set GB in the manual mode by turning the dial next to the menu button while in manual GB Mode till it reads 90 and just leave it there. That is why alot of detectors are factory preset for GB.
The new XP-DEUS is factory set at 90 for inland use and it says you can do a manual GB if you want to but this will be just fine for most general hunting useage on land. If on a beach wet /dry/ or salt or sandy areas as it will be lower than 40 you must do a GB as it will be down in the 20's and lower most likely so you need to do a Manual GB in that case.

 

[Elton]

If you tried everything here............ and your still not getting a Gb.... It looks like equipment failure.

If it's lack of experience check and see if a dealer is near you. Stop by.Almost all dealers are detectorists, and will be glad to help you.

If a Findmall sponsor is near.............. they will "More" than be glad to look over, and see if all is well, and will teach you how to ground Balance.. if it's operator error.

Would you consider posting here exactly how you ground balance .... every step if you don't mind typing it up..