Fisher F75 working procedures & Tips

[Jeb]

Hi there,
For any one new to the F75 ,it may help if i just give you a few tips on using your F75 . I would never wish to advocate i am an expert with any detector , but if i can point people in the right direction, then i feel you can then expand on this info i`m setting out.
 First , Ground balancing . This procedure is a very important issue to be taken seriously. You are advised to do it although The Auto  "Fast Grab" procedure is adequate in most soils.
Rather than waste space in describing the fast Grab , please follow the Manual steps on this. But can i just mention ,that i Fast grab about every 20 minutes. Keep an eye on your "ground mineralization graph" on the right hand side of your meter console watch for any fluctuation in your Graph when GB` ing. Make a note at first what the readings tell you ,what state the soil is when your GB`ing..
 Once you have fast grabbed (GB).................Select your working s.
 Assuming your wanting to search in the DISCRIM  mode (on the left of the control panel)......
Set your sensitivity on say 75 to start. No particular reason just set 75 for now.
 then push the menu button again and select DISC LEVEL with the settings knob.. Set this at 4 .
 Then push the Menu again and select notch with the settings knob.. Make sure this is ALWAYS on 1 .
 (unless you want to delb into Notch procedure)
 Press menu again & turn Settings knob again to,"  # of Tones."
 This is all down to a matter of choice on this setting. I when i first got the F75 used 3 and even 4 tone, but i soon found that although these modes give you the higher squeal on Silver . They can also give out ghost signals which can waste a lot of time looking for when really they are not there. So my advice is to use Primarily TWO TONE ,(2)or if you want to go into Zero discrim then Single tone is the better ,but thats a whole different ball game strategy.
DP (delta pitch) is not advised
Now press menu once more, and turn the setting knob till your in Process #.
 Here you have 4 different search modes.
dE (default process)
JE  (Jewelry process)
bc (bottle cap)
and finally, PF (plowed field)
 Again these are modes which you personally will decide what YOU want and feel confident in.
 Can i just say that it in general for UK soils, its better to Ignore bc mode , but again, thats just mine ,and a few others opinion.
( De mode)  is a General purpose mode basically.
 (PF mode) is a very good and versatile mode for uneven ground and pasture.
 (JE mode) is the Turbo of the F75 . This is a VERY sensitive mode and is perfect for searching for the tiny stuff in. This detector eats Cut quarters for breakfast in this mode (if they are there ) Watch your sensitivity though in this mode . But ,Too high sometimes and you will have an adverse affect on this detector.` 50 `is average, but up it higher till it ceases to become stable then back it off a few turns till you can get a pretty good stability in the noises to be able you to recognize the "good signal " when you hear one.
 Just a quick mention on the search swing on THIS detector. On most detectors it is always advised you search slowly. Now, not so with the F75. A quicker than the average swing is advised for this detector, but when in seriously trashy ground you will have slow your sweep speed down in and amongst the iron. This doesn`t mean to say you should up your Step pace. Just your swing pace . 1 second per sweep is about right, from left to right .and a bit slower in the trashy ground.
 Now going back to Sensitivity !
 I always start as high as i can without Erratic gurgling and hurdy gurdying playing in my ears. Try to set the sensitivity  so that you do not hear "excessive noise". Tune the Sensitivity  so that there`s an  even sounding or ,just a tiny bit of noise in the back ground of your Ear phones..  SILENT running is NOT advised .
You can run sens high in PF & DE mode and if your hearing is OK ,you can pick the good signals out from the chatter. But you have to listen carefully for them.

You may wish to go for maximum depth and start hunting in (motion)ALL METAL Mode.
 This is an excellent mode to hunt in ,as you get NO GROUND AFFECTS to contend with as you do in the Discrim modes.
 Firstly switch over from the Discrim mode to the All metal mode on the right of your Screen .
Adjust the threshold to just audible. Then adjust the Audio pitch of your detector . i think mines at 5.
drop down to SENSITIVITY now and start off at about 75 .
 Now  Ground balance the detector(fast grab). If your not sure on this Follow the steps in your User manual to do it . You will soon get the hang of it and not have to use your Manual..But always make sure that you fast grb over a "clean" piece of ground,do not fast grab over a bit of ground that has a bit of metal underneath it.
Then start Digging. If your not comfortable with Manually GB`ing then Fast grab procedure will be OK . Keep your ears open for the good target each way sounds and Dig nothing under 18. It will be rubbish.Coins etc will be up in the 40`s figures or roundabouts. OK i know cut quarters may be missed by ignoring anything under 23. but if Cut quarters and halves don`t float your boat, there no problem.But if you want to detect cut quarters and halves, just dig from 18 and above ,then you will almost certainly catch them in the 18 - 20 bracket. You`ll soon get the hang of what figure not to dig under after a few digs. A lot of high squeals will be Iron up in the late  90`s, but as i said watch out for the figures in the Medium /High end bracket to be good targets . Raising your Sens right up can be Ok as long as your comfortable with the sounds. Its all down to finding what you are comfortable with .
 Also,I have added this paragraph on also as i think its an important addition from NASA tom..

Put  your Discrim mode on. Use PF mode ,and sensitivity at around 80. Also stick your Discrimination on " 6 " and (Very important) stick your tones on MONO TONE (single tone).
When this set up is on it allows an excellent Iron see thru capability to be introduced on a site where it is littered with iron bits of junk and it masking the non ferrous targets.
Many detectors will shut down on these circumstances.
The F75 and the T2 are the only detectors available that will readily tackle this (pretty common) scenario with a good unmasking success rate. Now heres the gist of this.
With the F75 discrimination on 6 ,and Monotone ,...... The moment you invoke a different tone ,such as 2 tone or three tone or four tone, the Discrimination even though its on "6"....
 Will BECOME instantly a discrimination of FIFTEEN by you switching the tones out from mono tone to any other.
 The reason for this is any target that is between "6" and "15" will now audibly report as a LOW TONE(iron tone)
This is a Big problem for many reasons.
Any target that is ABOVE 15 might read a Higher tone(tone frequency depending on what tone option invoked)
Most people do not want to dig Iron, and most people will miss masked non ferrous targets when "monotone" IS NOT SELECTED So ,mono tone is very very useful .
 Do not dismiss it .
 The T2 with a disc setting of "21" and mono tone will be a similar thing.

 Anyway i hope this bit of info will help you to wards running your F75 in a pleasant and rewarding way.
There is much much more to the working of this F75 & i`m sure In fact i obviously know there are lots of things i have omitted to convey to this post but i can`t discuss everything in one go ,but this is just a few hints to help you get you up and started pretty quickly.
 Have fun.

[maxine]

Very helpful post Jeb. 

[The Doc]

Excellent post Jeb. I've had my F75 for about 15 months now, and have found some decent stuff with it, including cut quarters, which do float my boat. On Sunday I tried all metal motion mode for the first time, and was quite impressed with it. But what is the advantage of manually ground balancing on land?

This is what the manual says:

In most situations, it is preferable to push the trigger switch to activate FASTGRAB
automatic ground balancing. Generally, it is best to first let the computer automatically
cancel interference from ground minerals. However, for gold prospecting, searching on a
wet saltwater beach, or searching in an area with so much metal trash that there is no clean
ground for the computer to sample, we recommended that you manually ground balance.

[Jeb]

Excellent post Jeb. I've had my F75 for about 15 months now, and have found some decent stuff with it, including cut quarters, which do float my boat. On Sunday I tried all metal motion mode for the first time, and was quite impressed with it. But what is the advantage of manually ground balancing on land?

This is what the manual says:

In most situations, it is preferable to push the trigger switch to activate FASTGRAB
automatic ground balancing. Generally, it is best to first let the computer automatically
cancel interference from ground minerals. However, for gold prospecting, searching on a
wet saltwater beach, or searching in an area with so much metal trash that there is no clean
ground for the computer to sample, we recommended that you manually ground balance.

Hi Peter,
Truth is,  since having the Original Mk1 F75 i had these instructions with it in the Bigger manual.
"Manual Ground Balance can only be performed while in an All Metal mode, but the resultant setting will carry over if you change into Discrimination mode. See the previous section on Ground Balancing for instructions on how to use this feature.
We suggest that you manually ground balance using only the MOTION All Metal Mode. The result will be more accurate than when using STAT All Metal Mode."
 And this is what i`ve always done as per (Hi lited) instruction in All metal mode. Its just habit really. There "maybe" no advantage over fast grabbing. but again to be honest with you, I`ve never tried to fast grab while in ALL METAL mode . I was told to Manually do it so that`s what I`ve always done.

[edit]
 Since I wrote this post quite some time ago ,it has come to be found that ,Ground balancing by the "fast grab" method and not the manual method, is just as good as manually ground balancing when in the All Metal Mode..
 

[roy skogvold]

Hi Jeb and thank you very much for your tips. Since I tried your tip for the "Iron see thru" settings. It's wonderful and I really enjoyed my last three days, walking behind 2 guys with xp Deus and one with excalibur, and picked up more than 100 coins and relics they missed. So it's really working. Some of the coins was literally underneath are above big rusty iron nail, and it still picked up the signals. This helped me take my detecting to another level, so to speak. The "xp Deus-gang", where even a bit annoy when I yesterday found this hammered 1/24 Thaler from the 1620s where the just had combed the ground. The Deus is I'm sure a wonderful machine, but the F75 kicked some Deus a**  that day