Newb: F75 Sensitivity Befuddlement

Hi All,

New to this forum, but not to detecting. So, howdy!

I made a deal with someone for an early model F75. I've been reading like crazy on this device while waiting for it to arrive. When I got it, I gave it a deep cleaning and got it looking shiny and new, again. I also opened up the battery box and took care of the rattling external speaker. All seemed well. I assembled it, and was a bit surprised that the unit did NOT seem overly sensitive to EMI. This is inside my house, ten feet from my wireless modem. With all I'd read, I fully expected this thing to drive me crazy with the noises it should have been making (as my old Omega did!).

I took it out to a ball park/complex, thinking I'd have to turn the sensitivity way down due to the EMI there. Not only did I not have to turn it down, I was able to turn it up to about 82! It did better than my ATP did, side by side, with the EMI. Now the telling point: I laid down a few targets to do a side by side depth comparison, expecting the F75 to way outperform the ATP. It did not. In fact, it was about on par, or maybe a half inch to an inch worse in an air test (about 6-7 inches on a quarter). Very strange!

So, this being an older unit, and thus me not being afraid to open it up, can anyone give me any advice on what I might do to boost the sensitivity of this unit? Are there pots in the head unit I need to adjust that may, over time, have unwound themselves a bit?

Thank you!

Don't know about the adjustments, but your unit seems not to be up to par imo. You never mentioned your disc setting.
My DST f75 with the small coil ( didn't want to put stock coil on), with disc 0 de process sens 60----with these settings in air test on quarter I'm matching you for air test depth.

And I'm assuming you are talking stock coil, right ??°

Did you get another coil with your unit??
I'd try it just to see if things improve.

Thanks tnsharpshooter. Disc was 6, de process, and 11" DD. I only have that coil. Definitely want to pick up the 5" DD, though...

Gotta day I already like this model! Super light and I like the tones better than my ATP. And it his hard on nickels. I won't be missing gold with this machine! Unless it's deep, that is... Hahaha!

Try your detector with 4 disc and around 80 sens on a dime and see what you get in de process. Quarter too if you want.
Remember disc 6 setting is a neutered disc setting for horsepower/depth.
Four disc your detector should really amp up vs 6 disc.

Will do! Thanks, tnsharpshooter!

Dig gum,

Since you are new here, you might not have seen this.

Not to confuse you but this thread talks about a F 75 with boost, and later on talks about the new DST units.

There is still however some good info in this tremendous thread.
In your spare you might consider reading.

[www.dankowskidetectors.com]

If you get some time we could try another coil...let me know!

Thanks, again, guys! I set my disc to 4, and it made a significant difference. Definitely more sensitive to emi, and hit on a quarter a couple of inches higher (just placing it on the ground, since I don't have a test garden) than it did yesterday. I hunted for a half hour at my boys' school and found a delicate garnet and sterling lady's ring, and a small handful of clad. Deepest target was only about five inches. Can't wait to get to an older site and see how it does. So far, I'm loving this machine, even if it doesn't quite live up to my original expectations!



Edited 1 time(s). Last edit at 12/07/2015 02:40AM by Diggum.

Glad to hear. Sterling ring ain't bad at all.

Remember you can try freq shift to mitigate emi. Better to experiment on buried target at site you are hunting. It can make a great deal of difference at times.

Thanks for that thread link, tnsharpshooter! I finished it tonight, and with the info there I was able to successfully hunt in 99 sens with 2 tone and 3 disc. Woohoo! Going to take it for a spin tomorrow at what should be a hunted out park. We'll see how it goes!

which park?

I'm thinking Kaseberg. Want to join me?

Diggum Wrote:
-------------------------------------------------------
> Thanks for that thread link, tnsharpshooter! I
> finished it tonight, and with the info there I was
> able to successfully hunt in 99 sens with 2 tone
> and 3 disc. Woohoo! Going to take it for a spin
> tomorrow at what should be a hunted out park.
> We'll see how it goes!


You are welcome.

Actually NASA Tom deserves the thanks. His knowledge on the detector platform---Grand!!!!!