New Fisher F4 help. EMI problems? Something else?

[p1atypusx]

New Fisher F4 help. EMI problems? Something else?
I received a Fisher F4 I purchased on eBay today. I went to bench test it and it went haywire. Figured EMI from inside so I went outside. Not any better but I was able to air test some coins and pull tabs. But when not reading it was still all over the spectrum. I don't think the EMI could be that bad, could it?

Here's a link to a one minute video showing what it's doing.

[video]http://youtu.be/3wFfJ6_HCnM[/video]

Is it just bad interference, or did I get a bad detector? The coil is connected well. Could it be bad coil? I turned sensitivity down and still bounces all over.

Any help please.
Thanks in advance.

 

[goldman55]

Read the Ground Balance part. Manually ground balance it. Not Preset.

Bill

 

[REVIER]

This is actually normal for many F4/F2 users when they fire it up around their homes the first time.
Could be a problem, it happens but it is rare, and from watching the vid I don't think so.
All the F series units are just ultra sensitive to EMI....some sites are good, others are not so good and some are horrible but the horrible kind are usually few and far between so don't worry.
That area you first tried is just an unusually bad one, but a little noise and chatty behavior is just something we learn to deal with and you might have some at other sites especially if you hunt on max sense like I do.


Wifi travels through walls to the outside easily, buried or overhead power lines are near this location for sure, you might even be in direct line of site from some sort of powerful tower even a mile away or more that can cause this.

One site does not make a good scientific sample...take it other places like to parks and see how it acts and it won't be this bad...probably.

Turn down the sense if you want, the F2 and the F4 and the others seem to be way overpowered out of the factory even on power up sense settings...turn it down even to the the lowest sense setting and you should should still get pretty deep and find the good stuff with at least a little less jumping and chatty behavior.

My F2 can still find a small piece of chain at 5" with the sniper coil on the lowest sense settings...that bigger coil should do even better.

After using the F2 and the F70 I can also tell you this...
Even at sites where you get some good jumping behavior when you roll over a good target these units seem to get down to business and tell you with a stable repeating tone and number on the screen, but you need to learn to notice this because it might be fleeting with other jumping going on all around it.

It just takes a bit of practice and you will find this out.


Some tips on using the F2, they transfer to the F4, also...

http://www.findmall.com/read.php?37,1902523,1902523#msg-1902523

 

[yowow#1]

I owned an F4 for a couple years and never did anything like that, as a matter of fact it was perfectly stable at max sensitivity. I also had an F70 and it was a little chatty at high sensitivity, but again nothing like that. I would say bad coil, bad detector or really bad EMI. JMHO... Good luck

 

[WhatTheBeep]

^^^ What Rev said.

Also, I noticed in your video the chatter would pretty much stop when you held the shaft nearly vertically up in the air (coil was nearly parallel to ground). My F2 and F70 both are much more prone to EMI problems (when they are present) when the coil is not parallel to the ground, but put it on down to start sweeping and it usually quiets down. I've got to say that's some of the strongest EMI problems I've seen in your video, though.

Anyway, I think you're machine is probably fine.