Multiple Frequencies vs. One - The advantages?

[earthmansurfer]

Do you guys with the V3(i) prefer to use one frequency at a time, all three or a combination (e.g. - to check targets). I'm looking to get a new detector next season and I'm just doing my H.W.

Is it a big advantage in your opinions to have the multiple frequencies as opposed to say, just access to three individual frequencies? And if so, how?

Is there a big difference in depth between multiple and just one? I'm in Germany and a lot of the coins are copper (some silver) and are pretty small on average, perhaps dime sized. The olders are sometimes hammered.

Any ideas, pointers, experiences would be appreciated regarding frequencies.

Thanks a lot for reading my thread and hopefully responding

 

[gilfordberry]

my two cents...

first, you sacrifice some depth in using multiple frequencies over a single frequency. Whites explains that that is because the transmit power is divided among the three frequencies rather than concentrating all the available power into a single frequency. Fortunately, with the V3 you have the option of using all three, or any one of the three frequencies alone (you can't use two of the three at the same time). The biggest advantage I have found (so far, and I'm pretty much a newbie with the V3) is that since differenct metals "hit" harder on the different frequencies (gold and nickel hit the 22.5 KHZ hardest, copper and brass hit the 7.5 the best, and silver seems to respond highest to the 2.5 KHZ. US clad coins also seem to hit hardest on the lower frequency). This is a very valuable tool in helping to identify the metallic content of the target. It's not infallable - you know that there is always a trash target around that mimics a good one - but it sure helps. For example, rusted, flattened bottle caps often VDI at or near the same number as a US quarter - and sometimes sound very good, too. There is a "bottlecap reject" setting on the V3, but if set too high, good targets begin to break up as well as bottle caps. BUT, if it sounds like a quarter, VDIs as a quarter, but DOESNT hit hardest on the 2.5 KHZ frequency - it's a bottlecap. Haven't found a single instance when this test was wrong. Now, if I could find an equally accurate test for gold vs. pull tabs......

 

[Aurium]

I tend to favor 3 frequency modes. I like being able to pick through the litter pretty effectively by paying attention to which frequencies it hits hardest on. Depth with 3 frequencies I suppose is a little less, but in my case it doesn't seem to matter at all. I've picked quite a few coins from 8 inches plus, and w/out the 3 frequencies I probably would have skipped those targets.

I am able to pick through bottle caps now w/out discrimination on. But curiousity gets the best of me and I still dig a few of them, occasionaly uncovering masked targets. (not often, but it has happened a few times)

I've tried the deep silver mode quite a bit which is single frequency, but I really find I miss the ability to look at the 3 frequency signagraph.

 

[Neil in West Jersey]

Due to the heavily hunted sites I detect, I have been leaning toward single frequency 7.5 Khz lately. While Best Data gives more accurate VDIs and shows the dominant frequency, Single frequency definitely punches a bit deeper. 7.5 KHz is a good all around frequency to use. Silver and copper coins will still respond very strongly due to their high conductivity and relative size, without sacrificing small buttons and gold.

So it really depends on what you are looking for. If you are looking for modern coins and jewelry multi frequency is the way to go, but if you are looking for older coins in hunted out sites you will need the extra depth that single frequency can provide.

I often switch from one to the other depending on conditions.

I hope this helps!
Neil

 

[earthmansurfer]

Thanks guys for the informative comments. Do most of you try to turn the discrimination sensitivity (maybe even the Rx power) up when using three frequencies to try to get more depth?

Have any of you played with the recovery speed? I'm curious if it can be programmed like some of todays very very fast detectors.

Thanks again, I'm really interested in this machine. Have narrowed my next machine down to this one and the Deus (I'm in Europe).

 

[Neil in West Jersey]

Thanks guys for the informative comments. Do most of you try to turn the discrimination sensitivity (maybe even the Rx power) up when using three frequencies to try to get more depth?

Have any of you played with the recovery speed? I'm curious if it can be programmed like some of todays very very fast detectors.

).

I keep my RX as high as possible without falsing (I noticed I can raise the RX a bit higher with Non-Stereo Mixed Mode than with Stereo). My typical settings are the following which need to be tweeked in each frequency setting:

RX Gain: 12 (if conditions allow it)
Disc Sens: 93 (if conditions allow it)
All Metal Sens: 74 (if conditions allow it)
Recovery Speed : 95
Filter: 5Hz Band Pass (if conditions allow it)

As I have said, I tend to run a little hot to get the most out of it. Sometimes it borders on "unstable".

You can program the V3 to be a fast detector or a slow detector depending on your preferences and ground conditions. The V3i is a combination of the best features and benefits of every detector made. That is the beauty of it.

 

[earthmansurfer]

Interesting settings Neil

So, the RX Gain of 12 is essentially increasing the size of your coil. (Not so much a depth thing I have heard - Mike Hillis mentioned it effectively increases your coil size). This tells me your ground is relatively clean?
You run your disc very hot, as I do.
A recovery speed of 95 is right in the middle (This is recovery delay in the manual if I understand you correctly).
Your filter is for very non mineralized ground and a very slow sweep speed.

Regarding your settings, why would you have your recovery speed in the middle but your filter and sensitivity set to go so deep? Why not a very slow recovery speed, like wouldn't it sort of need to go along with the other settings. Understand I have never swung a V3, so I'm just trying to understand your settings. Sounds like fun!

Have you tried running the Tx Boost at all?

Thanks for your time Neil.

 

[Rob (IL)]

90 to 100 is a slow recovery speed. 45 would be a fast recovery speed. RD should be based on ground, and proximity of targets and sweep speed, actually it should be set to where it works best.

The easiest thing to do is when you find a good deep target adjust settings until you get the best readings, not rocket science.

 

[Neil in West Jersey]

90 to 100 is a slow recovery speed. 45 would be a fast recovery speed. RD should be based on ground, and proximity of targets and sweep speed, actually it should be set to where it works best.

The easiest thing to do is when you find a good deep target adjust settings until you get the best readings, not rocket science.

Unlike other detectors, such as the White's DFX, the recovery control on the V3 and V3i is a Recovery Delay, not a Recovery Speed. The higher the number, the slower the sweep speed and filter settings should be to match.