GPX 4000 Auto Tune

Today I took a 4000 for test drive and was happy (impressed in many ways) with performance. One thing I noticed however which I'm not sure is usual is that after hitting Auto Tune the Manual Tune had a reading of 250 which thinking about it now seems quite high. So I'm just wondering from the experience of forum members, is this level (250) within the 'normal' range for the machine to settle at after an Auto Tune, or am I getting two separate tune functions confused (i.e. Auto Tune and Manual Tune), thinking they are the same and one, when they are actually seperate?

Any help/opinions much appreciated guys.

Cheers, Cal

Stoppsy's the best one to answer that question that i now of he gets his rig running nice. Most of us have found that the machines have a sweet spot usually between 90 to 110 give or take a few well thats what i have found anyway.. Auto tune automatically selects a frequency, Manual tune is user adjust hope this helps.. Did the 4000 come with a user manual if so read it front to back then keep reading it non stop and you will find a lot of answers to your questions that was the advise i was given and it was great advise, Some more advise is low and slow and concentrate hard, listen for the slightest of changes to the threshold. All the best mate..

Cheers Cal
Dani

G'day mate.

The auto tune cycles through all the frequency's and selects the quietest one that it can find. 250 is fine it all depends on the conditions of the day. However, as per your users manual, the lower frequencies give a slight advantage on deep targets compared to the higher frequencies or something like that. I like to keep my frequencies below 100. Somedays it's just too noisy. Don't worry about it if its on 250. If the threshold is stable you won't be as likely to miss a very weak target response. If the threshold is noisy then it will waver about and when you get one of those slight target responses, you will dismiss it as threshold noise.

Dicko..

hi cal
as dani said the sweet spot is between 90 and 110, and a good thing to do is leave the manaul tune on the screen at the back while detecting
and when you get a bit of emi just turn the adjust knob up or down a couple of numbers and it should be good again,
nice,quick and easy that way
cheers fencejumper

Dani, sounds like good advice, thanks. I've been reading the Manual and forum posts the last couple of days and I am probably suffering a little info overload @ moment. I just rechecked the Manual and yes, as I read it, Auto Tune and Manual Tune are the same function. I was fairly sure that you could Auto Tune and then tweak the Manual Tune dial a couple of numbers either way if needed.

What makes me question the 250 level is just what everybody has said above re: sweet spots and ranges for deeper/shallower gold. John Gladdis's suggested GPX 4000 settings given in a post on both this and another forum mentions a level of more than 100 for shallow gold and less than 100 for deeper gold and lists the Factory Preset at 128 (BTW this not given in Manual).

As you all likely know, the upper maximum level the machine goes to is 255, so a 250 Auto Tune seems pretty extreme when thinking in terms of the above generally accepted sweet spots etc.

Dicko, the threshold was smooth, and the machine seemed to perform OK, which as you say is I guess the most important thing, I can see how much more 'looking deep into such a subtle threshold' is required for the GPX over previous platforms. If you reckon 250 is fine from experience of having seen your machine choose this high level, great, that's what I'm asking everyone. I assume a (supposedly occassional) high Auto Tune level reflects very high variation in EMI from day to day (is this 'the' major challenge in using GPX's compared with earlier platforms?

Fencejumper, thanks for your advice. Does this mean you think Manual Tune is the 'cheapest' way to minimise EMI (compared with say dropping the Gain level by 1)?

Thanks for everyones replies and advice so far. Any more still very welcome.

Cal

hi mate, i sometimes run 96 to 100 but if the 4000 is still not running smooth i go to about 150.... with the thresh turn it down so the white line is level with the auto button. if it's still not running smooth just keep going up in numbers until it's running sweet... or the other thing is run the detector in quite and if it's still not running smooth run it in smooth timings. once you have it worked out they are a great detector...
cheers
stoppsy

Cal wrote:

Fencejumper, thanks for your advice. Does this mean you think Manual Tune is the 'cheapest' way to minimise EMI (compared with say dropping the Gain level by 1)?


Cal

yes mate try dealing with emi with the Manual Tune first, if that does not work then try other methods, using quiet audio should be a last resort though,
most of the time just going up or down with the Manual Tune will do the job.
cheers fencejumper

stoppsy wrote:hi mate, i sometimes run 96 to 100 but if the 4000 is still not running smooth i go to about 150.... with the thresh turn it down so the white line is level with the auto button. if it's still not running smooth just keep going up in numbers until it's running sweet... or the other thing is run the detector in quite and if it's still not running smooth run it in smooth timings. once you have it worked out they are a great detector...
cheers
stoppsy

Sorry to fencejump Cal but:
Stoppsy, I only ever run my 4000 in smooth. If you don't mind telling, what settings are you using these days when not in smooth? I'm using an 8'' now since seeing your successes, (just got it last week, got one on the first use so I think you are on the right track).
Sparrowfart.

hey SF, i'll post the video off the settings...the nly thing is i have changed is my thresh i have turned it down so iy's just a slight hum



i hope this helps use guys out..
if the ground is realy noisy i'll go into quite and if it's still noisy i'll go into smooth

cheers
stoppsy

Hi Guys,
I use a 4000 and find that the auto tune tends to select frequencies over 200. I mainly go out in the triangle.
My understanding is that the higher frequencies are more suited for smaller shallower gold.I autotune in patch mode which I have adjusted the gain to 15 to amplify the background noise. I then switch back to general and adjust the gain between 8 and 10. I usually have motion in very slow and audio in deep. I find this gives the most stable threshold.My aim is to get the threshold as steady as possible as I struggle to concentrate if its wavering too much. I think a lot comes down to personal choice and detecting style. The slower I go the more I pickup. Also having your head in the right place is another important variable.To find gold I need to get into the "Zone". When i'm not I know I won't find any.

I find in the area i detect that around 120 seems to run nice and quiet, I just leave it on 120, give or take 5 or 10, and leave it on manual tune in the menu, and tweak it as required during the day like fencejumper said. Normally I'll tweak it 2 or 3 times during the day to get rid of EMI, normally 1 or 2 either side of 120 works fine.
I used to autotune every time that the detector got noisy, I wouldn't go back to doing that again, it takes time, it doesn't always get the best channel and I'd much prefer to use the manual tune.
Just my 5 cents worth,
Good luck

thanks for the video m8 and the info cotained, will try them out with a little variance and see how i go,, thanks heaps for the effort m8, appreciate it

happy hunting
Steve and Lea

Thanks for everyone's replies. As odd as it seems, Auto Tunes of 200 or more seem to be par for the course, which is really all I was asking, but everyones willingness to give further advice and comments is much appreciated.

Staples, I think I know exactly where you're at there. I see it as two zones, the first is where you can let your gut instinct tell you where to search, even if the area doesn't 'look right' visually - I think this is too easily overlooked if you're too eager to get gold that day. The second zone is riding your machine's threshold with complete familiarity. From my initial experience with the 4000, its quietness is unsettling after alot of use with the 2200 ('jitterbug warbler' but a great machine!) and 3500. The zones I found with these two seem to have more in common than what I imagine the 4000's will be. I guess in my haste to be comfortable with the 4000, I need to first be comfortable that any automatic functions of the machine are in fact working correctly, especially with such little (or apparently little at this stage with my limited experience) feedback through the threshold.

Anyway, thanks again fellas, great forum.

Cheers, Cal

Reply with quote

Re: GPX 4000 Auto Tune

Post stoppsy Yesterday at 10:13 pm
hey SF, I'll post the video of the settings...the only thing I have changed is my thresh I have turned it down so it's just a slight hum


Thanks stoppsy, that has certainly given me a lot to play with. I can't even imagine running a gain of 10 or 12! But obviously it is a goer, so I will be doing a bit of fiddling. first I will have to peel off some of my preconceived ideas. Having done this I should be able to learn something.
thanks once again.
Sparrowfart.

no probs SF, i hope this works as it has been for me... i was told by a person that test ran the 4000s if your tune is 200+ it's good for your fine (small gold) hunting, this is why i run 150 if going deep with bigger coil go 96 to 110 there abouts...
i hope this helps out
cheers
stoppsy