normal for F70 to be this noisy?

caheaton said:

Hello, my day to day unit is an F2 which I enjoy very much, but a couple years ago I bought a used F70 that I tried a couple of times and then stored away. Tonight I have it another go, but soon remembered why I stored it away...it just seems too noisy. Even if I turn the discrimination all they way up (65, with a threshold of -5 and sensitivity to 50), the unit just chatters away with every swing. Most disconcerting is that I can still here the beeps from zinc pennies and tabs (using the target ID), yet these are allegedly discriminated out. With the F2, once they're discriminated out I don't hear them...with the F70 they still just chatter away (I'm using 4 tone mode, by the way). About the only sound that seems blocked is the lowest level iron grunt.

Is this normal or is there a problem with my unit? (I did do the ground balance routine prior to starting out). If it's normal, I'm beginning to think the F70 just isn't for me....shame since I love the little F2...it's chatty but not anywhere near as bad.

Click to expand...

Is this happening at many sites or all the time?
Will it quiet down on lower sense?
Sounds like there might be a problem.
Mine doesn't work like this like...ever.

Call Fisher, might be a bad coil or other issue.

What you describe is not normal for the F70. I agree with Digger27. Call Fisher and see what they have to say. Good luck. The F70 is a great detector.

I was afraid of that (detector problem....). Bought it used so no recourse, especially since it was a couple years ago. I've tried it at two sites...both are school yards that are littered with quite a bit of trash (mostly foil and pull tabs). Haven't tried it with sensitivity below 50 yet nor tried changing the frequency, I'll try those before contacting Fisher. Quite disconcerting that the discrimination setting seems to have no effect on what I hear coming out of the machine (except for not hearing the lowest iron grunt). I was hoping that maybe it was just a case of the signal on those items being strong enough that they overrode the threshold setting (which I've only run as low as -5).

Sigh.....

Just an update. On treasurenet a couple guys gave me a tip to try....performing a software reset on the detector. After doing that, the detector seems to be behaving correctly n air tests sitting on the dining room table. I'll have to check it further in the field, but at least I know the discriminator is functioning correctly in the air test (zinc penny dead silent with discriminator turned up all the way, turn it down a touch to enable zinc and the same zinc brings about a nice middle tone). Guy said it's not uncommon for the F75 to need a reset on occasion.

Here's the reset procedure: press and hold menu and ground grab while turning on detector. When '88' is displayed release the buttons. Detector is reset. Hopefully that's all it needed.......

Yeah that reset comes in handy every once in a while...I've not had to do it on my F70 for 4yrs now..If I get playing with the programs too much that seems to be the thing to do..reset and start over...

Interestingly, a lot of us hard core F70 users tend to go with completely different set ups and programs and hunting styles even, so theres a lot of help for you here if you need it..Congratulations on getting yours working!
Mud.

Sorry, I just assumed you knew about and already did a reset.


On this one notch can be tricky.
With low disc all areas above that disc can be notched out.
With high disc all areas notched in below will actually be notched in.
Just reversing the notch setting procedure sometimes, most times DOES NOT get rid of the notch even though on the screen functions and slashes it might look that way.
Set a notch point anywhere in any section and the whole section will be notched out completely.
Any tab number notch you set drops out all the tab numbers below or even above that notch number in that tab section for instance, or back in at high disc.

Always do a factory reset after messing with notches and anytime things get a bit quirky....as you have seen it seems to bring it back in line.

Also a tip on that gain setting...
The sense is not like many other units out there... 50 is actually not 50% power, 33 is not 33% power, 10 is not 10% power and so on.
All settings are way higher than you might logically think they are.
Set the sense at 1 and see how deep you can get to prove this to yourself.
This thing can get noisy in some settings but even then will stop and tell you it is swinging over something good.
You can also set it to be silent if you want by manipulating the sense and thresh and be surprised at your detectors depth with any coil.

Now go out and try it at those two sites and more.
This is one amazing machine if is working right...jaw dropping amazing once you learn it in trash, iron, sites you need to go deep...everywhere.

For me: Threshold was key

Howdy, can check this url as well:

http://metaldetectingforum.com/showthread.php?t=203161

Especially reply 16 (threshold -3 worked great!) etc... for "me", one key to making my (at that time) chatty F70 simmer down, was the threshold setting - yup, diff of night and day.

Can't recall of hand, without re-reading the thread, whether it was higher or lower setting that made it much quieter.... but that's what did if for me.

Its a powerful machine and once learned... awesome.

Ron

P.S. Went and read it... seems the Higher the threshold, the deeper and smaller items to be found... but the chattier it was... I found a happy medium. You may want to experiment etc with Threshold.