Delta Pitch

Lately I have been trying delta pitch on the F75 LTD in a pasture found a 2 cent 1865, in a park that has been hit hard I found 1940 wheat penny, 1891 IH and 2 1889 IH pennys

A little background information before revealing what I’ve discovered about the Fisher F75. More than 10 years ago I started inquiring about some old locations I hunt. Most of the locations are old, shut down schools where coal was used as a heating source for decades. Before the EPA was birthed most people did whatever pleased them when it came to disposing of waste, regardless of what it was and these old school sites are no exception. The burnt coal waste was spread over many acres of school property which created some extremely harsh ground conditions. Grass and weeds find it hard to get a start and most areas are void of any vegetation. Most of the school grounds look like Martian landscapes with small BB size or smaller pieces of coal waste everywhere. This material attracts to a magnet with little effort and can reduce depth of all VLF detectors by well over half. In fact until recently maximum detection depth was actually 2-3”, any target deeper would give a solid iron audio report if any sound at all. After many years of hunting these areas all but completely unsuccessfully I finally purchase a White’s TDI SL.
It turned out the SL opened up these old sites and many nice coins and relics were unearthed, but not without many trials and numerous adjustments. Case in point: one particular area had been, in my opinion hunted out with many different VLF machines over a 10 year period and I was certain there were no good targets left. I had been hunting about 15 minutes and all the SL was giving were very short audio reports, which sounded more like chatter or EMI and not targets. This prompted me to increase the time delay to about 15 “which increases the time before a transmitted signal is analyzed” thinking the small pieces of coal waste were the short reports I was hearing. Continued hunting another 5 minutes and noticed the short audio chatter continued but not to the same magnitude. Stopping and increased the delay to around 17 and off I went hunting again. Suddenly I noticed the machine was running very quiet, to quiet. A minute or two later and a very loud low tone, which on the SL means a high conductor, I stopped and reduced the delay to 10 and found my definite answer. The coal waste was causing all the ground chatter and false audio reports. Increased the delay to 17 and recovered a wheat penny around 4” deep. Now to be honest I had to stop for a moment and think about what just happened. Decided to start over I returned to where I began hunting and discovered I had passed right over many good targets. After digging a few more wheat’s I decided to start checking these targets before digging and discovered if I decreased the delay most of these targets became the short sounding audio reports I had heard earlier. The PI was just the trick to discovering some nice coins deeper than 4” in these barren areas. I must add the SL is not the best choice to make if there is an over abundance of nails because of the very limited discrimination capabilities of this particular machine. As a final note I must admit this machine has opened up a lot of hunted out harsh ground sites. Now on to the next story, but this time with my Deus and the Fisher F75 at a different location.

While hunting one day at a different location I noticed a lot of broken/clipped audio reports from the XP Deus in a particular area, and of course remembering the experience with the PI machine, I started adjusting as many different settings as I could think of and finally found that the full tone mode (only changed the audio function) provided the best of audio signals, dug some and found they were, indeed, good targets. At that point I was well pleased with the Deus, and after discovering this I continued to dig many more good targets. After a good bit of time I decided to break out the F75 and hunt the same area hunted with the Deus. Amazing to find there were still many more targets in this area, all giving extremely short, more like chatter audio reports, I started experimenting with the different settings on the F75. Sensitivity up and down brought no change in the audio. Finally going to my old faithful 1F with discrimination of 15 and some, only a very small percentage of the audio signals began to smooth out, but not enough to prompt me to dig. Not happy with the results I decided to try each process and nothing changed the signals. Then remembering the only changed needed on the Deus to detect similar targets was to change to full tone, but the F75 doesn’t have that choice, well I was kind of wrong. Changed to dP tones and wow it did just as good as the Deus, in fact the audio was slightly better, more smooth, cleaner start and finish of the audio signal. Interesting to say the least, so I decided to change and go through each of the process and found the dp tones was the setting that was necessary to hunt this area. Interesting note, my understanding of dp is it only changes the audio, has nothing to do with depth, sensitivity and discrimination, but I believe there is more to dp.

"Great stuff markg.
A real thinking-man's assessment.
Like you (and like many others too) I try to cover sites with several detectors over several years.
I wonder how the new Impact would do there...with their New small coil?"

Very interesting, thanks for posting your findings Mark.

I have a site where the soil is high in alkali and the audio reports from my F75 (3H tones) and Racer 2 (3 tones) really suffer there. I wonder if the full tone option would help, certainly worth a try, and nice to see that the new Impact has a full tones mode too.

-Cal

markg Wrote:
-------------------------------------------------------
> A little background information before revealing w
> hat I’ve discovered about the Fisher F75.
> Changed to dP tones
> and wow it did just as good as the Deus, in fact t
> he audio was slightly better, more smooth, cleaner
> start and finish of the audio signal. Interesting
> to say the least, so I decided to change and go th
> rough each of the process and found the dp tones w
> as the setting that was necessary to hunt this are
> a. Interesting note, my understanding of dp is it
> only changes the audio, has nothing to do with dep
> th, sensitivity and discrimination, but I believe
> there is more to dp.



Edited 1 time(s). Last edit at 02/25/2017 08:00PM by Cal_cobra.

edited

“I don't care that they stole my idea . . I care that they don't have any of their own”
-Nikola Tesla



Edited 1 time(s). Last edit at 02/25/2017 07:09PM by Keith Southern.

Excellent Info Mark!!

I find myself as I Go forward with these tone machines enjoying the delta or 99 or full tones more and more...
these are where the SQUEAKERS!! are coming to light it so seems..

Great write Up!!

Keith

“I don't care that they stole my idea . . I care that they don't have any of their own”
-Nikola Tesla

Keith Southern Wrote:
-------------------------------------------------------
> Excellent Info Mark!!
>
> I find myself as I Go forward with these tone mac
> hines enjoying the delta or 99 or full tones more
> and more...
> these are where the SQUEAKERS!! are coming to ligh
> t it so seems..
>
> Great write Up!!
>
> Keith

Keith I found the delta-pitch audio on the F75 to have a somewhat harsh sounding, artificial sounding, digital representation of the 0-99 TID spectrum.

How does the DI99 full audio setting on the Impact sound compared to the dp audio on the F75? Can you apply the Impact DEEP mode to the DI99 mode?

Thanks!
Cal

Cal_cobra Wrote:
-------------------------------------------------------
>
> I have a site where the soil is high in alkali and
> the audio reports from my F75 (3H tones) and Racer
> 2 (3 tones) really suffer there. I wonder if the
> full tone option would help ......

Or .... you could simply get an explorer !

Haha, just razzing you. You kept up even-steven with me, so I don't see how you say you were having troubles. Looking forward to our next trip there !

I guess the tone could be adjusted to take some of the harsh shrillness out by lowering the tones?

------------"Cz's still bad to the bone".------------
Living on a big ass Astroid.
The woman that got my rib,I want it back.

i have tried delta pitch a few times and do like it. i need to use it more.. i use 99 tone on my 705 and really love it..

Quote
basstrackerman
I have tried delta pitch a few times and do like it. i need to use it more.. i use 99 tone on my 705 and really love it.

The 'Delta Pitch' of the Teknetics T2, Fisher F75 and Nokta Impact assigns a tone for each TID number giving you up to '99' audio tones or pitches.

The Minelab X-Terra 705, like the original X-Terra 70, has a settling labeled '99' but that's simply a reference to the multi-tone function. What it does is assign an audile Tone or Pitch to each of the Discriminate Notch Segments, of which there are only '28' so if all Disc. segments are accepted, you can have up to '28' Tones, not '99.'

Monte

Oh i know .. i just meant that i do like multi tone on that detector and the tones are pleasant to hear. 28 tones over the 3-4 i normally use.. the f75 sound more digital.. but doable..

It has a Deus full tones type report..More blendy..Calliope type response..With some vco nuances...Creates SQUEAKERS...

On the F75 and T2 the 99 tones are more segmented.

Keith

“I don't care that they stole my idea . . I care that they don't have any of their own”
-Nikola Tesla

Keith Southern Wrote:
-------------------------------------------------------
> It has a Deus full tones type report..More blendy.
> .Calliope type response..With some vco nuances...C
> reates SQUEAKERS...
>
> On the F75 and T2 the 99 tones are more segmented.
>
> Keith

So the Impact's more analog sounding then the F75? That's what I'm hoping for. Best audio of any machine I've used was the Sov., if they'd modernize that with TID and a modern fast processor, what a machine it would be!

Great topic, Mark's info very usefull and detailed!