teknetics gamma question..??

[_lee_]

Hi guys this is my first post, im not even sure if its going to work but hey here goes.

I have a teknetics gamma 6000 with the standard coil & ive had this machine a couple of months after moving up from the ace 250.
I have a couple of questions which are , when i have iron notched out i can't hear iron right, but if i place a coin beside the iron i dont hear the coin either.
So why is this happening surely the coin is a different metal so i should hear it..??
Also what is the difference between discrimination & notch apart from notch taking out whole sections at a time..?
One more question.. is there any advantage of using the manual ground grab function over the auto ground grab..
I hope someone can help answer these questions
thanks in advance..!!

 

[caleb]

All I can say is that I rarely use the notch unless I'm only wanting a few quick coins. I use the discrimination at about 16, it wipes out small iron nails and stuff like that. It still allows you to hear the iron grunt and if there is a coin next to it you can hear the coin as well. I don't have any experience with the standard coil instead I use the 11" dd that gives a much narrower slice of the ground. With the standard coil it may not work quite the same, you should still hear both. With the notch in place you have to swing really slow to give it time to cut out the iron and give the coin tone still.

 

[MarkCZ]

With notch and discrimination you can disc out a much smaller segment as compared to the notch. Also another thing that the notch system can be used for (on many machines) is you can run the disc up to max and still get the upper coins, at that point you can go back and notch in the nickel range.
When the disc is set low you can selective notch out certain target zones, so if the disc is set high you can go back and notch in certain zones.
I'm not sure the Gamma will do that, the Omega does and unites like the F75 do.

Mark

 

[Monte]

I have a teknetics gamma 6000 with the standard coil & ive had this machine a couple of months after moving up from the ace 250.

A pronounced improvement in versatility on that upgrade!

I have a couple of questions which are , when i have iron notched out i can't hear iron right,

That is generally correct. Now you have to ask yourself WHY you use Notch Discrimination and why such a high rejection level? Also, I am curious what Tone ID option you have chosen and the types of site you hunt? Also, what detector(s) have you owned and used other than the Garrett Ace 250?

With the entire Iron audio/TID range eliminated (rejected), you have a lot of iron rejection and a broad bias to iron targets. Rejected, you won't hear them.

... but if i place a coin beside the iron i dont hear the coin either.

The main cause is Target Masking. It is not easy for many detectors to respond to a non-ferrous target that is positioned too close to ferrous object, especially if there is TOO MUCH iron rejection, which causes too much bias to iron. it's important to understand the iron object size and shape as it related to most typical iron littered sites. Usually, we are most bothered by iron nails and they can be rejected with a lower Discriminate setting of somewhere about '14' to '18' with the Gamma and Omega. When you notch the entire 'Iron' range it is knocking out all the way up to a VDI or '40', which is a lot more negative rejection towards typical iron nails.

So why is this happening surely the coin is a different metal so i should hear it..??

Different metal, yes, but with too much rejection you make it more difficult for a detector to process and respond to a nearby target, even if it is of a higher conductivity. Two targets laying together, or very, very close to each other, are usually seen and processed as a 'blend' of the different alloys, and that causes a good response to be heard from a better desired target, but the visual and audio ID can be lower reading/sounding, even as if a piece of unwanted trash.

This is one reason why I very seldom use Notch Discrimination, preferring to use a variable Disc. setting to just barely reject the most problem target at a sites, and usually that is nothing more than an iron nail. That requires a lower Disc. setting. I'd suggest setting up you Gamma the more efficient way rather than using an Ace 250 sort of Notch Disc. method. Only increase the variable Disc. just to the point where the problem target is eliminated.

Also what is the difference between discrimination & notch apart from notch taking out whole sections at a time..?

That is exactly what the difference is. A variable Disc. setting allows the operator to fine tune the rejection level to "just enough", whereas the Notch Discrimination method rejects an entire range or segment of conductivities that can be very broad. Notching has a use, for some people in some applications, but most savvy detectorists will use a variable Disc. setting to only reject the annoying trash and not create a lot of bias by over-rejecting such as using a notch segment.

Monte

 

[_lee_]

Thanks for your replies guys, you are providing me with some very useful information & it is helping me to understand the working of my machine better.
In response to monte's question yes the only other machine i have owned is the ace 250 so the gamma is quite a different machine.
The type of iron i am hearing and getting fooled by are normally larger peices, bits of chain, farm machinery, ect. that often give a good high end signal (80ish) but once i start digging turn into a low tone 15 or so.
I normally detect with a friend who has just brought a new deus 2. . maybe its because his machine is so good that its making mine look & feel a bit rubbish.. theres me wandering around getting false & duff signals & theres him digging hammered
coin over & over again in the same area..But i suppose i shouldnt really try to compare my

 

[nw_detector]

This thread is a little old so my reply is a bit late. But even if so others might still have the same question so I'll go ahead and try to answer your question:

Look at page 14 of the Gamma manual (Section 5: Volume) -- it states that the higher tones will be inaudible below a volume setting of 4. So check your
volume level and make sure it isn't set too low. Poor headphones will also make it more difficult to hear those high tones at lower settings.

It doesn't surprise me that someone has this question since I'm guessing most people will bypass that part of the manual -- I mean, how difficult can a volume
setting be? However, my experience with the Gamma is that a lower volume setting doesn't seem to quiet down the speaker all that much. It's more like
tone control than a volume setting -- or call it tone discrimination since the high tones will completely disappear but the lows are still somewhat loud
even at the lowest settings.

So for question 2, Notching and discriminating are sort of the same thing -- only notching gives a little more control. Let me explain further: Discrimination
starts at the lowest range and goes up from there. Every ID above the setting will be detected and every ID below will be ignored. Notching does this but also
allows you to include or exclude categories separately. For example, lets say you set your discrimination level very high to only include the dimes,
quarters, and silver stuff. But you also want nickels. Without the notching ability you can't include the nickels without also including EVERY category in between.
The notching ability allows you to add JUST the nickel category and still ignore everything in between. You can also do the reverse and notch out any single
category you don't want.

And as for the manual vs auto ground balance... There are times when a detector will have a hard time balancing. Or maybe you want to fine-tune things because
you're not happy with the automatic setting. That's when you need to make the adjustments yourself. Also, some detectorists like to run their machines a little on
the positive side ("hot") or maybe on the negative side depending on the soil type, the metal type, and/or the size of the objects they are hunting. That also requires
the ability to manually adjust the ground balance setting. I'd explain further but I'm still trying to understand this myself -- I've read the Gamma manual several
times and still don't fully understand (e.g., "positive hot rock", "negative hot rock" -- define please!)...

Hope that helps and good luck with your Gamma!

 

[ToddB64]

Monte, et al.,

My ultimate dream discrimination system would have Notches having a range of selectable conductivity numbers within each notch window. Only the selected number or numbers would be discriminated. No other numbers below or above those selected within each notch would be affected (discriminated), nor would any other Notches below or above the one(s) being used be affected. ( I hope you understood that last phrase.)

The particular conductivity numbers and volume of numbers included in the range within each Notch window would be design decisions. In addition, to reduce the display window size, the list could be setup for scrolling when making selections.

I believe my "dream" discrimination system would obviate the need for a co-system of the type we now have that discriminates all targets having lower conductivity numbers than the selection.

Perhaps there are already metal detectors that have what I have described, but I'll bet they are expensive.......anybody know ?

Your thoughts ?

Thanks in advance for any replies.

Todd

 

[knarfj]

Monte, et al.,

My ultimate dream discrimination system would have Notches having a range of selectable conductivity numbers within each notch window. Only the selected number or numbers would be discriminated. No other numbers below or above those selected within each notch would be affected (discriminated), nor would any other Notches below or above the one(s) being used be affected. ( I hope you understood that last phrase.)

The particular conductivity numbers and volume of numbers included in the range within each Notch window would be design decisions. In addition, to reduce the display window size, the list could be setup for scrolling when making selections.

I believe my "dream" discrimination system would obviate the need for a co-system of the type we now have that discriminates all targets having lower conductivity numbers than the selection.

Perhaps there are already metal detectors that have what I have described, but I'll bet they are expensive.......anybody know ?

Your thoughts ?

Thanks in advance for any replies.

Todd

Hey Tod,

At the risk of the forums hangmans noose I think the White Spectra would fit the bill for you. www.whiteselectronics.com/spectra-vx3

To see a quick, getting started, video of its capabilities take a gander at: www.youtube.com/watch?v=-rr5yWUcC1s

Pay particular attention to the video between 4:40 through 4:55.

If $1100.00 isn

 

[ToddB64]

Monte, et al.,

My ultimate dream discrimination system would have Notches having a range of selectable conductivity numbers within each notch window. Only the selected number or numbers would be discriminated. No other numbers below or above those selected within each notch would be affected (discriminated), nor would any other Notches below or above the one(s) being used be affected. ( I hope you understood that last phrase.)

The particular conductivity numbers and volume of numbers included in the range within each Notch window would be design decisions. In addition, to reduce the display window size, the list could be setup for scrolling when making selections.

I believe my "dream" discrimination system would obviate the need for a co-system of the type we now have that discriminates all targets having lower conductivity numbers than the selection.

Perhaps there are already metal detectors that have what I have described, but I'll bet they are expensive.......anybody know ?

Your thoughts ?

Thanks in advance for any replies.

Todd

Hey Tod,

At the risk of the forums hangmans noose I think the White Spectra would fit the bill for you. www.whiteselectronics.com/spectra-vx3

To see a quick, getting started, video of its capabilities take a gander at: www.youtube.com/watch?v=-rr5yWUcC1s

Pay particular attention to the video between 4:40 through 4:55.

If $1100.00 isn

 

[knarfj]

Yep, it is a bit up there! Besides at times I struggle with my $10.00 Wally World cell phone, what hope would I have mastering all the bells & whistles the subject machine has to offer.

Hope I didn't wrinkle too many feathers.

Take care & HH

 

[razerback408]

Monte, et al.,

My ultimate dream discrimination system would have Notches having a range of selectable conductivity numbers within each notch window. Only the selected number or numbers would be discriminated. No other numbers below or above those selected within each notch would be affected (discriminated), nor would any other Notches below or above the one(s) being used be affected. ( I hope you understood that last phrase.)

The particular conductivity numbers and volume of numbers included in the range within each Notch window would be design decisions. In addition, to reduce the display window size, the list could be setup for scrolling when making selections.

I believe my "dream" discrimination system would obviate the need for a co-system of the type we now have that discriminates all targets having lower conductivity numbers than the selection.

Perhaps there are already metal detectors that have what I have described, but I'll bet they are expensive.......anybody know ?

Your thoughts ?

Thanks in advance for any replies.

Todd

i have a gerrett gta 350 that will do that