Find's Treasure Forums

Welcome to Find's Treasure Forums, Guests!

You are viewing this forums as a guest which limits you to read only status.

Only registered members may post stories, questions, classifieds, reply to other posts, contact other members using built in messaging and use many other features found on these forums.

Why not register and join us today? It's free! (We don't share your email addresses with anyone.) We keep email addresses of our users to protect them and others from bad people posting things they shouldn't.

Click here to register!

Need Support Help?

Cannot log in?, click here to have new password emailed to you

Changed email? Forgot to update your account with new email address? Need assistance with something else?, click here to go to Find's Support Form and fill out the form.

F75 LTD Upgrade problem?


Hi everyone,I recently sent my f75 ltd that I have had for 5 years in for the upgrade mainly for the dst around electric fences and other emi. Anyway,I got it back Friday and went to my test garden. I mainly ran my old machine in all metal but occasionally in disc mode. Ok,i started with the factory 11'' coil in my garden in 9.0 and all metal,boost process, sens 98 and it gb'd around 60 and you couldn't even hear a .58 cal minie ball buried at 8" so I went to the 6" minie ball and you could barely hear it and vdi was showing iron,next I went to the 3" minie ball and it sounded like it should but the vdi numbers were all jumping from 8-22. I then switched to disc with sensitivity 95,2F,boost process and it basically had the same results. Tried the same tests in 9.1 and had the same results. So,i then switched coil to my round 5'' coil and did the exact same tests and in all metal you couldn't hear the 8" minie ball but at 6" and 3" it was loud and gave steady numbers of 45-55. In disc mode you could hear the 8" minie ball an pretty good numbers. This is so strange because with my old detector using the 5" coil you could hear the minie ball at 8" and the numbers were jumpy but it would jump up in the 45-55 range and in disc mode it wouldn't hit it. A couple questions,does it sound like my coil was somehow damaged or does it sound like ive got a lemon? Are you guys seeing better depth in disc than all metal? Does Fisher not test the machine after they upgrade it? Something is definitely not right with mine. Its so bad with the 11'' coil that I had to but a .58 cal minie ball an inch from the coil to get a solid reading of 50-55. Any help will be greatly appreciated


New member
I would immediately contact Fisher..Get a call tag and send it back for calibrations... If it won't do what it did do..Something is wrong..


Well-known member
Doesn't sound right.

Here are some coin test numbers, you may want to compare to some coin numbers on yours.

But it sounds like it needs to go back.

Ron in WV


New member
Since the detector works well with the 5" coil, it sounds like the 11 incher needs calibrated or recalibrated or even replaced.. In talking to a tech last week he said they don't calibrate their coils with the actual detectors itself, they do the calibration of the coils on the bench completely separate from the detectors.. Maybe they'll send you another coil or have you send in the coil for evaluation.
I think Fisher will take good care of you

Good luck


The AM mode on my upgraded F75 doesn't work as good as my older models. It isn't nearly as loud on the deeper targets. I think your machine sounds really bad though. 8-22 id on a 3 inch bullet is screwy and you should still be able to hear an 8 inch one. I would give Fisher a call.


Thanks everyone. I sent it back to Fisher and they swapped everything out. The new one they sent me is pretty amazing. I took it to a place next to railroad tracks and electric fence where my original f75 ltd was almost useless because of the chatter and mainly the falsing,this upgraded machine was so quiet that wasnt even sure it was working right until i pulled a few minie balls out at around 8" each. Numbers are alot better on this upgraded one too.
Glad to hear it's working good for you now.

Out of curiosity, what date does your screen flash when you turn it on now?
Glad it worked out for u. I just sent mine in 2 weeks ago. How long did it take? hh rick in mi
Hard to believe they sent it back to you like that. I purchased an original F75 and out of the box it didn't ground balance.Sent the whole thing back and they replaced the coil. Seems quality assurance is hit and miss. I only use original Fisher detectors (Cz3D, 1270, Coin Strike)