Rcpt Ack of F75 Ltd prototype

So far....... I have limited experience with it. And Florida fat/thick/swollen/tall grass is just starting to die down for the winter..... to the point of where I can perform valid/controlled environment testing. It is a bit deeper over the 11" DD coil ..... only whilst in one of the boost processes......... but to what degree I can not answer comfortably. I am very much a stickler to 'controlled testing'. Within the next few weeks...... I "will" have an answer.

INconclusive results with F75 15" coil as follows:

1) Ergonomics/design of this coil is quite good. I could swing it all day. ((( Although I could swing a CZ-20 all day also ))). The 'placement' of the mounting of the coil to the stem is ideal. The coil is slightly nose-heavy....... which aids in keeping the coil more parallel to the ground..... and slightly further away from the body/feet. I did feel the need..... and wanted....... a longer lower stem so as to have a wider sweep.

2) I do believe this coil should only be used by professionals......... or .......... well educated in the application/use of this coil. Reasons in 3) and 4) .... and somewhat 5) below.

3) This coil (thus far) appears to have approx 15% more EMI susceptibility. It is a large antenna (inductive loop). It can only be utilized in areas that have confirmed/verified minimal EMI. THIS IS IMPORTANT! It is a show-stopper if not strictly abided. Gains/attributes of this coil can NOT be 'realized' if EMI is present.

4) Mineralization. Thus far in my testing...... If mineralization is fairly low..... this coil 'appears' to perform per design. With higher mineralization.... the excessive dirt feedback renders/nullifies the additional performance of this coil. ((( I know this is a 'vague' statement IRT mineralization level ))).

5) Ironically....... this coil can be used in medium/low, low and no-trash areas. ((( More 'vague' terms ))). It is best to use this coil in open fields where targets are fairly sparse; yet, if you incur 'some' trash..... this coil is 'reasonably' good with adjacent target separation. A bit better than I had anticipated/preconceived.

6) The ID accuracy of 'known' (test-standard) targets is accurate.

7) Performance gains of this coil can only be 'realized' whilst in any of the 'boost process' modes.

8) The PP (pinpoint) ability of this coil is exceptionally good.

9) Let me state it this way: The 5" DD coil has approx 6-1/2" footprint. A 10" or 11" coil has approx 10" or 11" footprint. This 15" coil has approx 13.5" footprint. This is a law of physics (diminishing return bell-curve). The ground coverage vs size of this coil is not readily apparent...... yet is larger than the 11" DD coil; yet, is not as large (envelop) as common/visible expectations.

10) The electronics likes a bit faster sweep-speed with this 15" coil. The MP (microprocessor) operates better with faster input.

I can give no depth data yet. Because of this......The jury is not out (yet). In my real-world field-testing yesterday (all day with 15" coil)....... I did not find any 'beyond normal depth range' targets. I cannot test this coil in my test-garden.... as...... my 'low' EMI conditions are not 'low' enough; subsequently, on-site real-world testing is required. This makes it a bit more difficult to have a 'controlled environment' for testing... to have any form of validity; hence, my slow ability to have (and release) data IRT this coil. I may need to perform dry silica (dry beach sand) testing to start having some valid data to present. It would only be logical to ascertain approx 15% more 'realized' depth gains.......... as EMI appears to be at a 15% increased rate. I did manage to test some 'standardized' test-standard targets in open air-tests...... (where lower levels of EMI authorized/presented)........ and the air-tests were phenomenal................ knowing this could never be ascertained in dirt.

I will also state this: This coil does not seem to be desensitized to small/tiny targets......... as would be expected for such a large coil; however, larger-than-coin sized targets do present greater ranges of detection in air-tests thus far. I just simply (and only) lack verified/valid 'depth' answers.

Just picking up on a minor point re. lower stem length. It is possible to drill ( with care/skill) a new hole closer to the top end of the lower shaft, and relocate the spring-button. This could gain you 1/2 inch / 15mm in length. The joint overlap still seems adequate.

Interesting Tom as always. I see you haven't been able to verify depth on the 15" yet, but I've seen with MANY other detectors that once you go above the 12" or so coil size, depth doesn't seem to increase much if any, depending on the model. (I guess you need a unit that can physically put more gain into the ground?)

I just ordered a 12"X13"NEL Tornado for my E-Trac. From what I can research I might be able to get an extra 1" or 2" depth with it (and more sensitivity and better performance).

Just returned from the beach..... DRY SAND ONLY..... from extensive 15" coil (with F75 LTD) testing. EMI existed.......... but was very low. I utilized only two standardized test-targets. A modern U.S. nickel.... and a U.S. Type-1 $1.00 gold coin. After several hours of testing; results are as follows:

F75 always remained at Sens '99' (due to minimal EMI), noise channel of 'F6' and Grnd Bal '90'. I never changed these settings. The only variables were Disc 1 and Disc 0....... 'bp' and 'cl'. What I am looking to discover is..... if the 15" DD coil can simply produce more depth over (vs) the 11" DD coil.

First target tested: the tiny $1 gold coin. Interestingly, there were absolutely no differences in performance between the 11" coil and the 15" coil..... in regards to depth performance. 'bp' to 'bp'.... (11" vs 15" )........................... 'cl' to 'cl'.... (11" vs 15" )........................... Disc '1' to Disc '1'.... (11" vs 15" ).......................... Disc '0' to Disc '0'.... (11" vs 15" ). It is the strangest thing to see such a extreme 'parallel' in performance...... with such a dramatic change in coil size. The Type-1 U.S. $1.00 gold coin is truly a balanced quiescent pinnacle standardized 'test-standard' for the F75 LTD/SE. Remember..... dry sand depths will differ from dirt.......... so............ depth table as follows:

'bp' Disc '1' = 9.7"
'bp' Disc '0' = 9.8"
'cl' Disc '1' = 10.2"
'cl' Disc '0' = 10.3"

Switching the test target to a common modern nickel......... and the data results start to change. Remember.... the nickel is more than 3-times greater mass/size vs the $1 gold coin.

11" coil 'bp' Disc '1' = 13.1"
15" coil 'bp' Disc '1' = 13.3"

11" coil 'bp' Disc '0' = 13.2"
15" coil 'bp' Disc '0' = 13.3" (not a typo)

11" coil 'cl' Disc '1' = 13.4"
15" coil 'cl' Disc '1' = 13.6"

11" coil 'cl' Disc '0' = 13.4"
15" coil 'cl' Disc '0' = 13.7"

It is interesting how dry sand produces greater results..... as compared to dry dirt. Different mineralization structure.
With the larger 15" coil...... I noticed a greater span in ID numbers (bounce).... as compared to the 11" coil.
One of my conclusions is; Yes..... the larger the target..... the more 'effective' the larger coil becomes.......... AS LONG AS MINERALIZATION AND EMI ARE MINIMAL. If all Mason Ball jar lids were standardized in size/mass.......... it would be a interesting test to see the differences in performance between the 11" coil and the 15" coil.

Switching over to the all-metal mode....... with Sens on '99', Grnd Bal on '90' and noise channel 'F6'. Once again.... the $1.00 U.S. Type-1 gold coin produced exactly the results as posted above.
The U.S. nickel had yet another unexpected resultant. . . . . in the dry sand. The 11" coil added another 0.2" of audible resolution on the detection of the nickel....to both the 'bp' and the 'cl' mode.... with the depth numbers stated above...... but ONLY with air-gap enhancement. NOT buried 0.2" deeper.
The 15" coil is where a large differential was gained/realized. In 'bp' mode 0.6" of additional air-gap distance could be added.............. and 1.4" additional air-gap could be added to the 'cl' numbers above. Interestingly....... you would assume that with an additional 1.4" in air-gap depth..... that the nickel could be buried at least 0.2" greater in depth....and still be detected. NOT true. Air-gap gain ONLY!

In ALL of the all-metal testing.......... the audio reports were very clear/discernable; yet, no ID was generated on the VDI. The VDI screen remained blank throughout the entire process of testing..... due to TOO weak of a signal (not strong enough) to generate a VDI number.

Use your coils wisely. Select 'size' of coil to the correct environment........ including the size of the targets you choose to recover.



Edited 1 time(s). Last edit at 02/04/2012 02:31AM by NASA-Tom.

I have not seen any one shouting out , a must have coil and your tests show why

That was my experience with the 15" as well....no gain in depth on coin size objects but I noticed that it tended to ID the deeper targets with more consistent IDs. As Tom noted....the depth is virtually the same but whereas with the 11" coil the IDs would start to jump or be wrong at deeper depths, the 15" would have stronger IDs but no depth gain until you got into belt plate size objects and then there IS an increase in depth.

I do disagree with the balance of it though. I am not a weak fella and quite stout actually but the 15" DD is very unbalanced on the F75/T2. It is tolerable but I was only able to hunt about 2 hrs with it at a time before my arm was give out.

I found the SEF 12X15 DD to be a much better coil for balance (its lighter) and with the same results depth wise on small and larger targets. Between the two it was my pick. Not tried the NEL coils but definitely worth a shot.

Russian f75ltd test, the four coils in the ground
[video.yandex.ru]#

sens 90 bp disc 0 some signs of color

coin _ 2 kop (1814 year ) - 20 kop - 10 kop silver
11'' _ 31 cm - 27 cm - 21 cm
nel tornado _ 37cm - 33 cm - 25,5 cm
15'' _ 37cm - 33 cm - 24 cm
5'' _ 24cm - 22cm - 17cm



Edited 3 time(s). Last edit at 02/04/2012 08:21AM by Denari.

Translation for Denari post:


Coin.. 2 kopek (1814)........20 kopek....10 kopek (silver)
11''Coil.........12.2"................10.6"......... 8.3"
Nel Tornado.14.6"................13".............10"
15'' coil .......14.6"................13"..............9.4"
5'' coil...........9.4...................8.7"............6.7"

2 kopek= 7gm (copper)
20 kopek = 3.6 gm (silver?)
10 kopek = 1.8 gm (silver)

Hope I got this right



Edited 3 time(s). Last edit at 02/05/2012 06:52AM by TerraDigger.

Thanks for the conversion T.D. Now, what about the gm's into oz's ?..... just kiddin.

Bump! Hope this is ok...

LONG OVERDUE =

Directly to the point: Knowing “WHERE” to hunt with the 5” DD coil on the F75 SE has become more important than any/all other factors. On page 5 of this thread…… is the 5” DD coil real-world ‘performance’ report.

This report has a bit of a different (somewhat unsuspecting) twist….. as compared to the original findings. The performance of the coil remains the same; yet, its correct application (in the real world) presents maximum performance results….. primarily under a few unique circumstances.

The bottom line: COMPRESSED DIRT. (Compacted/condensed dirt)……. or areas that generate ‘compressed dirt’ scenarios. (High density dirt). What do I mean by this? Let me start by using an example:

Let’s say you have a 30’ x 30’ huntable area whereby the targets are at depths ranging from 4” deep…… down to 12” deep. . . . . and the area is fairly trashy. Now………. for what ever reason………. the area is selected to become a playground area whereby many kids will (now) play in this specific area….. for many hours every day….. for a few years. The kids will run around in this area…… pounding and pounding and pounding the dirt…….. compacting/compressing the dirt. Now……….. the dirt becomes compressed from all of the pounding. Dirt can compress….. and become more dense. Metallic targets do not compress. The end resultant: Targets that were in the 4” to 12” depth range…….. are now ‘compressed’ into…. say…. the 2” to 6” range/strata. The targets have not changed……… only the depth of these targets have changed. Now…………. because the targets are more-so compressed together …….. and in a narrower/shallower depth strata…….. the metal detector will (now) see the area as a MUCH more busy/trashy/target-rich area.

A few things have occurred. All targets (now) are within the range of the 5” DD coil. Targets appear to be louder, shallower and more abundant. Audio reports in the headphones will be substantially more ‘busy’. The “utilization requirement” of the 5” DD coil is now mandatory. The 11” DD coil has now become too big for this type of condition….. and will mask itself out……. failing to separate many of the targets….. due to its large (11” x 7”) size.

With all of my hunts/findings……….. this ONE COMMON DENOMINATOR has become the ‘secret’ to success for the 5” coil……….. opening up areas that previously have NEVER been able to be hunted in our detecting history. Compressed and/or dense dirt……… with abundant trash/targets. I have always steered away from these excessively abundant target-rich areas………. as current day metal detectors would completely fail to produce…. under such extreme target-rich, trashy (yet, extremely common) conditions. Now……… for the first time in history…….. we are able to hunt MANY additional areas with this configuration. And with this 5” DD coil coupled with ‘boost process’ configuration ……… sooo many more doors have been opened, such that,.,.,., a lifetime of detecting opportunities (now) exist.

Let me site a few more examples of ‘pounded’ and/or compressed dirt:

Sports activity areas
Underneath housing/building foundations
Walking paths
Playground areas
Farmland where animals have compacted/compressed the dirt
Automobile dirt roads

…… and the list goes on.

The most success has come from highly trashy areas with high-density dirt. Simply/only compressed dirt with minimal trash and/or targets….. does not constitute small coil justification. Compressed dirt with a low volume of targets does not constitute the ‘need’ for the 5” DD coil. . . . as the 11” DD coil would still remain the preferred choice.

And………… of all the different qualified scenarios……….. the best success has come from home-sites where the houses have been removed/lifted. The dirt underneath houses is very dense… (and inorganic)… with old/good targets not being very deep. Over the course of several decades …… I have ‘tried’ to hunt these areas…….. but no metal detector could handle the excessively high level of trash/masking…… usually in the form of excessive nails/iron. The 5” coil now “just starts” to open up these doors (sites) . . . . . to the point that it is worthy of vested time/effort. Through the years, I have tried other detectors (with small coils)……. and have not had the success that is presented with this current configuration.

Do not be intimidated by the tiny 5” coil …… falsely thinking that you will not cover much ground…. (((especially if you overlap your sweeps with this 5” coil)))……. which would falsely lead you to believe (make the statement) that: you will find less targets…… if less volume of property is analyzed. On the contrary. What you may find (and almost being the ‘norm’ every time)….. will be an abundance of non-ferrous targets in very small sections (localized hot-spots) of property. If you are finding a target every minute or two with this small coil…….. it does not matter that you are hardly covering any property; except, for the realization that you have a lot more ‘opportunity’ presenting.

Use the 5” DD coil and the ‘boost process’ wisely!

Very informative, thanks NASA-Tom. Thought provoking, for sure...

Steve

........ One of my primary intents is for this to be publically shared .... and somewhat in the form of a documentary. With more training for folks....... more 'discoveries' can be made by all.

Following this logic, would an AT Pro/Gold with the 4" sniper/snooper (sp?) coil be as effective?
I've just acquired an Omega 8000 with 5" and 11" DD and the stock elliptical concentric. Can I expect similar performance/depth from it w 5" as the F75?
I'm researching an appropriate shore detector, salt sand and mudflat, and lots of fresh water lakes and rivers. Not especially typical beach hunting as more very old location relic hunting.
Cheers
HH

Bob
Nova Scotia
Omega w 11" & 5" DD, 10" Con.
Cibola, Compadre
6000/D GEB Coinmaster

No..... not at all. The Omega with 5" coil is very limited in depth. The AT-Gold is also quite limited in depth with the small coil.
To the best of my knowledge...... it is only the F75 with 'boost process' employed ((( the 'bp' mode )))....... that is far superior than all other detectors with comparable coils. It is exclusively the 'boost process' that is making such a tremendous performance gain.

Thanks Tom.

Bob
Nova Scotia
Omega w 11" & 5" DD, 10" Con.
Cibola, Compadre
6000/D GEB Coinmaster

One more (requested) 'bump'.

Requested 'bump'.

Hi I am new to this forum, I have been an F75 SE (black) user for 2 &1/2 years now, my first machine was the AT pro. For a long time I ran the machine on 2F 80 sens BP, and hunted deep iffy signals with great success. However recently I have tried both single tone at 6 discrim 70 sens, and 2F 4 discrim 70sens. These two new choices made the detector MUCH deeper, however now when I dig iffy tones all I have dug is iron (square nails, bolts, large nails, etc.) about 10 wheats 4 Indians a bunch of amazing tokens and a rosey and barber dime. The amount of energy I put into digging these iffy targets has easily doubled and it seems it is because the detector is confusing me with the larger iron showing the flash of 90s numbers, then some low 20s--30's and maybe a 80 or 70 once in a while but very faint and jumpy. Just today I tried lowering the sense to 70/65 and I still dug at least 10 iron objects. However the depth meter is much more accurate when at 4 disc. & 2F--which I love. Forget 1-tone & 6 discrim lord! I dug that one barber and a couple Indians & tokens but EVERYTHING else was iron! and I mean I'm digging craters--thank god I'm still young but my back was killing after these digs. Do any of you have any advice on how to cut back these iron targets? I most skip over all the surface stuff these days and only go for deep hoping for old silver or gold or some neat relics. I always use the 'dig the plug and scan over it' technique. One thing I noticed is that even when I scan over the plug sometimes I get an even better signal on the deep nail/iron! I don't remember the detector giving me such misinformed hints when I was in 6disc. 2F... My only theory is that it is now going MUCH deeper and the deeper you go the less the detector can give you and accurate description of a target. The thing is, I have got dimes in the past that act just like these iffy nails & iron, and currently I'm trying to study the length of a deep dime sound because sometimes I'll dig a very short but semi-repeatable blip, and sometimes it will be a nice smooth but faint beep with iron grunts mixed in every now and then. Often when I turn another direction and scan over these the signal disappears or becomes pure iron grunts, however, I believe dimes can act like this too.
I appreciate your feedback and tips and thank you so much to everyone who has written on the forum you have been my education for the past two years!

NASA Tom wrote:

There's a big difference in 3-tones vs 4-tones on the T2/F70/F75 platform. When you are in 4-tone........ many older coins will report as the 3rd highest tone. If you are in 3-tone........ all of these coins will ID as a mid-tone........................ just like aluminum trash. Whilst in 4-tones...... and hunting for coins and old-coins........ dig the top two tones. Sometimes the 3rd highest tone (whilst in 4-tone) is called the 'zinc penny' tone. Yes.... zinc pennies do audibly ID as the 3rd highest tone.......... but so do silver Trimes, Half Dimes, Indian Head pennies, $5 Half Eagle gold coins, silver coins slightly masked, early generation wheat pennies......... and a host of other coins. Any of the tone option settings does indeed give modulated audio responses...... as long as Sens is approx '80' or below.

You will most probably (and highly recommended) find yourself hunting in 'bp' mode all of the time. You may need to adjust Sens/Disc/F1-F7 accordingly .... to mitigate EMI.... as per recommendations in the thread titled: Rcpt Ack of F75 LTD Proto.

If EMI is excessively severe......... check the tightness of the coil connector on the back of the control head. If EMI still remains too severe....... you may need to detect with a different unit............ but, verify ....by going to a different location.... that EMI is not 'maximum severe' anywhere/everywhere you go. In other words.............. if EMI is severe everywhere you go (including a trip into the country)......with moderate settings (say: Sens 50, Disc 10, 'bp' mode and proper F1 - F7 selection) ... you may have something wrong with your unit.

For Grnd Balancing...... Fast Grab is quite accurate...... assuming the dirt you use to Grnd Bal with is clear of metallic objects. You may want to manual-check the 'Fast Grab' method a few times. Chances are....... you will enhance your confidence in Fast Grab.

((( This thread should have been continued in the Rcpt Ack of F75 LTD Proto thread......... to maintain consolidation ))).
Reply Quote Report

You stated it exactly/correctly about the detector being quite a bit deeper in your newly discovered (Disc '6' and .... especially Disc '4') settings........ in regards to much weaker (deeper) targets coming to light. Yes, the deeper/weaker targets (that you are now seeing)..... are even more difficult for the detector to ID. (Most other detectors will not even detect this deep). THERE IS A LEARNING CURVE for this technique! IGNORE the ID numbers; yet, learn the audio! It will pay off. Sounds like you are approx 1/3 to 1/2 the way there...... yet.......... you may not know it. Once again......... ignore the ID numbers (on the excessively deep targets); rather, focus all of your tuition/learning-curve/attention to the audio. EXCLUSIVELY! This should 'quicken' your learning-curve.

((( For the most part......... I do not recommend Disc '4' setting whilst in monotone! )))

(Any of the tone option settings does indeed give modulated audio responses...... as long as Sens is approx '80' or below.)

The quote above was EXACTLY the info I was seeking! Bit confused now though...

So the only way to get modulated audio on the deepies is to have the sensitivity on 80 or lower??? Is this 100% factual & proven???? Wouldn't knocking down the sensitivity negate the whole purpose then? One would have to lose depth - by having a lower sensitivity - in order to receive modulated audio

I have to fish it out of the manual on my break, but, methinks I clearly remember reading that the 3H tone option DOES provide a modulated audio response...and it never mentioned anything about a sensitivity setting of 80 or lower if my memory serves me correct.

So Tom, I know you are a strong proponent of running as hot as possible - 99 sens. & 0 disc if able - thereby saying to forego the modulated audio. Why? In my limited experience, I always thought it was better to know when one has a deep target under the coil. Please explain...

P.S. - At an older spot where I'd dig everything, not having modulated audio is acceptable. But at a newer or fairly old/trashy place I normally forego the surface responses & prefer to only dig anything deeper than say 4 or 5". This is why this topic is important to me

Big thanks!



Edited 1 time(s). Last edit at 03/04/2013 01:50PM by njnydigger.

Simply glance at the depth gauge for a reference point.

Also...... when you find a deep target.......... try reducing Sens from '99' down to....... say '60'. In most cases, you will not lose the target; rather, only reduce the audio volume via a lower Sens level; hence, 'modulated audio'. This is especially true when Disc settings are '4' or below.
Very little depth (a non-linear amount) is lost when dropping Sens from 99 down to 60. . . . . especially with the stock 11" DD coil. (((A bit more depth is lost whilst using 5" DD coil))).

Yes...... in heavily masked situations of finding non-ferrous items in carpets of nails..... a higher Sens setting will present better audible unmasking/resolution performance (a paradox)........ giving the false illusion that depth is lost with lower Sens settings.

Ok, today I did about 2 hours in the field and stayed in 2F tone, 4 Discrim, 65 sensitivity. I tried to begin to analyze the actual "ring" of the tones, the duration of the tones, and the softness or faintness of the tones, as well as other attributes such as double blips (such as the ones tin-foil make) and scratchy beeps. I also analyzed the way the target pin-points, for instance: how deep the target sounded vs. how big of a "zip" my pin point made--or if it pin-pointed at all, OR if the sound dragged or had a strange sort of moan to it.
After all this and digging FAR less ferrous targets than I usually do, I began to realize the average deep coin sound 80--90% of the time, is a "clean", soft, and medium-to-long length beep/tone, and when it is pin pointed its not too short or small and it's not to big and also sounds "clean" and if I were to use another adjective: "round". Remember, I'm young, I'm an acrobat and fitness teacher by profession so I'm squatting and digging with sweat dripping down my face in 50-degree weather like I want it! Soooo out of the hundreds of small beeps I dig the one described above is "the" one your going to get a good "non-ferrous" target with the larger percentage of your hunts. However, I'm not saying I still don't dig a crap load of large iron because they just ring off like a deep coin no matter what sometimes. I did hear a slightly more "Boingy" tone though that I began to learn to disregard--but you really have to train your ear to hear the "edges" of the tones, how round (like the good targets) or sharp (more often bad targets), the same going for the pin pointing sounds.
Another confusing thing is the "dig the plug and scan the hole" technique. More often than not you can scan the hole and it will be a huge honkin piece of iron bolt--but it will still read like a faint coin!! the only difference being that your going to get mostly high 90's numbers. But hell-- coins act like that too! and sometimes you'll can the hole and the plug and nothing... DONT COVER THE PLUG!! DIG! There is always something in the ground beneath an F75 SE beep! So commit to dig if there is no sound in the plug of grass (always a bit of aluminum).
Speaking of which, you small gold guys. Just a tip, if you scan the grass plug and you get a solid tone--start breaking that thing up, if you scan it and you get that broken aluminum double-triple blip sound, and nothing when you scan the hole--kick that grass back over and move on--it's a bit of coke or tiny scrap of gum wrapper.
By the way, this hunt, some deep clad, and one very nice condition 1915 S wheat--one of the best years!! In a small square of park I have punded

D-Tone........ sounds like your skillset is rapidly increasing. Your write-up is good. A few more deep coins....... and that audio 'signature' will burn into your brain databank. Your good target -- to trash target ratio will greatly (is already) increase.

Something I rarely mention: The United States $10 Gold coin is called an "Eagle". They ID as a zinc penny. If you are in 3-tone on the F75 (or F70 & T2)...... they will be a mid-tone/trash-tone. If you are in 4-tone........ the Eagle will ID as the 3rd highest audio tone.

Thank you so much Tom! Sometimes I feel like we should call you the 'godfather'' I'm part of the family now haha! One thing, you keep mentioning 4-tone, which I don't use anymore because in other posts you avidly promote 2-tone or monotone due to the mental overload that 4-tone can induce from so many different beeps. Are you suggesting I switch to 4-tone, 4 discrim and start listening for these 3rd highest tones to get more deepies?
Thanks!!

If you are not in carpets of nails...... and you are 'old coin' hunting; I strongly recommend using 4-tone. The 3rd highest and the highest tones (the top two tones) will be the targets you are looking for whilst in 4-tone.

Thanks Tom!! One more note that was very interesting, and this is NOT by any means solid it's just a hypothesis, but I noticed when I was swinging at 4 Discrimination (BoostP) 2F, that the second hunt I slowed my coil sweep down to about a 3 second sweep maybe 4 feet wide and overlapping the machine was quieter and I got better sounds...! Now there could be many reasons for this:
A: Sweeping faster the machine must process and deliver many sounds at once--especially since the detecter is now in a boosted power mode (4discrim, bp) and registering more/deeper targets, which could in- turn confuse a man.
B: In BP and at the advanced depth/power surge of 4 discrimination the detector just performs better/more stable with a slightly slower sweep (and perhaps more accurate audio?).

Again, all speculation based on what I experienced on just a couple of 2-3hr hunts, I'd love to know what you think of this Tom! And thank you for all your brilliant help,
Cheers
(BTW I'm from Portland Oregon)



Edited 1 time(s). Last edit at 03/05/2013 07:30PM by D-Tone.

The microprocessor on the F75 can process at a mentally fatiguing rate...... especially if the coil is swept fast. Slowing the coil sweep speed down..... and you can individually hear more targets!