Discriminate vs. All-metal mode

[Kenkoehn1950]

I'm hoping to get some good information from experts in the field. Theoretical situation....u.s. Silver quarter found at 4" in discriminate mode. What depth in same ground conditions would I be able to find the same quarter in. Situation is not machine specific, but general. I have been told by some that I can expect twice the depth in all metal mode. True or false?

 

[Tom_in_CA]

I don't know what you mean when you say: " Situation is not machine specific, but general " Because the question can NOT be separated from the type detector.

All detectors are different. So you'd need to pick a machine to hone down the question. It's not true on all machines that you get "2x the depth when in all-metal". I'll give you one example: On the Explorer II (a very popular model to-this-day), the all-metal mode probably gives LESS depth than discriminate. It's a wimpy monotone + ratchet feature pinpoint all-metal mode. So annoying, that practically all Explorer II users simply don't use that all-metal pinpoint mode. And elect instead just to criss-cross the target to pinpoint in an "x-marks-the-spot" fashion.

On later explorers (SE or Etrac, etc..) they improved it with a VCO tone, but it still ratchets, so ... ... no .... there is not 2x the depth. And the question gets further confused because some people consider that if they have their machine to accept all-targets, yet have a tone-ID, that .... in their mind .... they are in "all-metal" (since they "hear" everything). But no, that's not true-all-metal. Since you can use your ears to discriminate based-by-tones. But on the other extreme, if you're talking an older VLF/TR (circa late 1970s/early 1980s), like the Garret Groundhog or whites 5000 d series I, then yes: all-metal went 2x as deep as discriminate did.

 

[Kenkoehn1950]

Thanks Tom. I guess I do need to be machine specific. I have a Whites Spectrum XLT and have been able to get down to about 4-5" on factory settings. Was thinking that if I went to all metal mode, I could find the older stuff. Just purchased an AT Pro and haven't had a chance to use it yet. Have heard my best chances for deep is Pro all metal mode.

 

[gleaner1]

All metal mode will give a bit more depth compared to a rock bottom scrim mode (allowing iron), maybe as much as ten percent. This regarding cz20 after twenty years. Ten percent is not enough to worry about for the average park and lawn guy. When I hunt a good clean spot I always use all metal and switch to scrim to get an idea if its iron, or silver, or in between, before I recover. If you use all metal in trash, you know the deal.

 

[flinthunter]

Something doesn't sound right. You should get way more than 4-5 inches on a quarter with the Whites Spectrum XLT. Are you sure your machine is set properly?

 

[gleaner1]

Your analogy is off, a radio shack will blow your brains out on a four inch deep silver quarter. Now consider a ten inch deep silver half dime in scrim mode. It might not make a sound in scrim mode. But in all metal mode, it very well could break audio in all metal. This can be seen in air tests on machines like the cz's.

 

[Kenkoehn1950]

Flint hunter....I have been running in factory mode on coin setting and seldom get anything deeper than 4-5"

 

[goldkey]

All metal mode should give you better depth. I only run all metal with the Ace250 and only discrim iron....all good tones need to be dug......Pass up on can slaw and you may be missing the gold. I never look at the coin mode or jewelry mode......

 

[gunsil]

Most coins found in undisturbed soil, parks, yards, schools, etc. that have never been landscaped, graded, or re-sodded will not be found much below 6" anyways, even if the coins are 200 years old. Minelab Excal and Sov users claim better depth in all metal and since they are primarily beach hunters this is important to them. I think Tim is correct that most modern machines don't get a whole lot of difference in depth in all metal like the early machines did. Ken, I think if you're not finding much below 4-5" it is just because there isn't much below that depth where you're hunting.

 

[Tom_in_CA]

Ken, the spectrum XLT ought to be able to get a dime to about 7 or 8". And a quarter to 8 or 9". I'm talking wide open locations though (beach, or clean field, etc...). Obviously if you're in a junky or nail-riddled environment, you can minus off some of the depth. If you're only getting 4 or 5" in disc, you're doing something wrong. Even in factory presets you should go deeper than that.

Are you remembering that this is a motion machine? (and a FAST motion machine at that). So for example: prop it up on a wooden table with no metal nearby. Get your factory presets all going, and a slight threshold hum. Now wave various objects in front of the coil (dime, penny, quarter, nickel, tab, foil, soda can, etc...). Notice that the fast you swing the coins, the deeper it will go. Hence in the the field when detecting, if you are on a suspected deeper target, momentarily speed the swing up over the target (criss-crossing as well) and .... you will increase the depth on the target, and get clearer ID. If there's a montage lot of targets, you might have to take short little quick "wiggles", albeit still fast over the target.

But when you go to all-metal pinpoint mode, "motion" is not necessary. (be sure to turn the annoying "ratchet" feature off of the all-metal pinpoint, by the way).

 

[airscapes]

Thanks Tom. I guess I do need to be machine specific. I have a Whites Spectrum XLT and have been able to get down to about 4-5" on factory settings. Was thinking that if I went to all metal mode, I could find the older stuff. Just purchased an AT Pro and haven't had a chance to use it yet. Have heard my best chances for deep is Pro all metal mode.

I think I have read that the you will need to alter the factory settings to get the depth the XLT is capable of. Have you checked out Whites forum?
XLT & Spectrum

 

[Kenkoehn1950]

Tom....great information! Two things I did not mention...ground in Denver seems to be highly mineralized and (embarrassed to admit this), I only look at targets that produce a loud audible tone. It sounds like I need to be paying a lot more attention to less audible signals.