Miracles Do Happen - Arrow 4" X 18" DD Coil From Detech

[Joe D.]

Good question V3i, 

   I have wondered the same thing!  Hard to compare apples to apples, but I'm guessing the Arrow wins hands down! All I know is I wouldn't have paid the premium price, at the time, for the Bigfoot, if i had known that the Arrow would have become a reality as  "quick" as it did!! Oh well, piece of detecting history to continue to play with! And it still finds the goods! Just that quirky winding configuration to deal with! 👍👍

[wltdwiz]

i just got an arrow for my goldbug pro & its a great coil stable & pinpoints super

its a winner

[Het]

On 11/12/2021 at 2:51 AM, EL NINO77 said:

The very idea of an 18 "long and 4" narrow coil of adequately weighing coil../ 770gram / is really good and interesting ..

....There are several 18 "coils for some detectors ... but count with the weight of the coil somewhere beyond 1 kilogram - specifically 1050 grams ...

.... Sweeping speed in detection...? ... It will depend on the type of detection and the detector ... but compared to the 6 "coil it will be at least 4X faster because you don't have to translate the coil so much ... and compared to the 11" coil it will be 2X faster .... ,, but I will be very important here also good separation properties 4x18 "ARROW coil because this coil has a width of only 10 cm ... which contributes to good separation ...

...From my point of view I will buy an Arrow coil for Whites MXT / DFX detectors and in my opinion it is very likely that the Arr coil will work well for the Whites  SPECTRA V3 detector on some frequencies and maybe also on 3F multi F ... as I prefer the Detector to work on Mix Mode. .... at a coil weight of 770 grams, these Spectra V3aj MXT detectors will be well balanced ...
 Wide range of options ... setting up these detectors .... getting the most out of this coil ....

  My 2. Alternative ......for the Arrow coil would be my Teknetics G2 detector ... because .this detector will work with this coil very well ... ,, similar to the Nel snake coil ... it's fast .. and also reasonably deep very stable detector .. detector with very good ID ..

Detech 4x18! WORST coil I ever put on a detector!!! Maybe 4". And the signal is so weak,you don't even know to dig or not! The only way I know is if i'm in my coin garden! What a piece of garbage!!!!!! Detecting 27 years. XLT,MXT PRO,and V3I! JUNK!!!

 

[phrunt]

It’s intended purpose is recent drop shallow targets and covering ground quickly, it’s not supposed to be deep and that in a way would make it counter productive, it’s a great coil.

[PimentoUK]

Exactly. Recent drops ( recent 20 years, maybe ) can be quick to recover, most of the time a good electronic pinpointer will hit them, so the 'plug' can be small and shallow. A mechanical pinpoint probe can help eliminate larger deeper items.
Arrow ( and Cleansweep / Bigfoot ) coils are basically 4" coils, so you should be expecting little more than 5" depth on 'coin-size' items. It will depend somewhat on the detector it's used on, you ( Het ) didn't state this important fact in your summary. I think a Fisher F75 ( which I own ) would have plenty of excess sensitivity available to get the best out of an Arrow.

I would expect if you were unhappy with it, it would've been easy to re-sell, with only modest financial loss.

[Tom Slick]

The Arrow does exactly what it was designed to do. It covers massive amounts of ground with each pass. Yes, it's depth is only 4 to 5 inches on small dime sized targets but at 18" long that's about the equivalent amount of soil to a 9" coil going 8 - 10" deep on each pass. If you're looking to cover large areas for recent drops, it does a great job. I wish it was a little lighter weight as it is noticeably heaver than a BigFoot coil but performance wise, it is equal to the BigFoot. I sold my last 3 BigFoot coils for $500 each and purchased the Arrow for a little less than $200 so I'm very happy with my purchase for my DFX. 

[Vladimir 06660]

The most incomprehensible is the coil?
1. For what purposes and in what cases can it be used?
This sensor will be strongly influenced by the soil - which will lead to a decrease in the sensitivity of the detector .

[PimentoUK]

Quote:"This sensor will be strongly influenced by the soil"
This is an important point. I have no idea how the ground pickup of this coil would compare to that of a 5" ( 125mm ) round DD, or a larger ( say ) 17" x 12". My hunch is that it is somewhere inbetween: more than the small coil, because it's longer ... but not as much as the 17x12 because it's not so wide. So I think "strongly influenced" is an over-statement.
The Detech Arrow is simply a long DD, like the Cleansweep. It's interesting to note that the Bigfoot has a different design. The Receive coil is figure-8 shaped, positioned above a rectangular Transmit coil. This means the ground pickup from the front half of the coil approximately cancels out that produced by the rear half of the coil. So a significant drop in total ground signal results. It's far from perfect: - if the coil is slightly tilted toe-up / heel-down, there will be a difference between the two halves.
Additionally, there will be much less EMI pickup, as the two halves of the '8' pick up similar radio signals, thus cancelling themselves. This could be handy in the urban environment where parks tend to be located.
The downside of the figure-8 coil is well-known: one half of the coil gives an inverted signal compared to the other. This would mess up the target detection and discrimination of a machine designed for just one half. Hence the Whites machines have a 'Bigfoot' mode that accepts either coil 'polarity' .

[Steve Herschbach]

On 8/11/2023 at 11:46 AM, Het said:

Detech 4x18! WORST coil I ever put on a detector!!! Maybe 4". And the signal is so weak,you don't even know to dig or not! The only way I know is if i'm in my coin garden! What a piece of garbage!!!!!! Detecting 27 years. XLT,MXT PRO,and V3I! JUNK!!!

Shows what happens when somebody that does not know what they are doing buys something they don't understand.

[Steve Herschbach]

17 hours ago, Vladimir 06660 said:

The most incomprehensible is the coil?
1. For what purposes and in what cases can it be used?
This sensor will be strongly influenced by the soil - which will lead to a decrease in the sensitivity of the detector .

If you read the previous posts on the coil and the coils like it you will understand it's use. It's all been covered before. As mentioned by the previous posters depth is not the main purpose of the coil, and would in fact would be detrimental for those like myself that employ it. Depth is related to the narrowest coil dimension more than the longest, so the Arrow and coils like it are elongated small coils. The are not narrow large coils. If you want depth, get a large round coil. This is basic stuff anyone who knows detectors should already know.

The coils are made for covering large areas and recovering shallow targets quickly. They are so effective they have been banned in many competition hunts. I prefer them for hunting jewelry in parks.

It is more the nature of the hunt... a numbers game. You are going to recover WAY MORE ALUMINUM than jewelry. So plugging and digging holes is a time waster and will destroy a park. I prefer using a Bigfoot and a pinpointer plus screwdriver. Acquire target, down on knee, stab with pinpointer, no signal, move on. If the pinpointer sees it, it’s shallow, so pop it out with the screwdriver. The key is dig all gold range targets but to make it easy as it is a volume game. Gotta be quick and easy. What I do is go aluminum detecting, and I accidentally find gold stuff sometimes! 

In theory you can hunt deep jewelry, but plugging for pull tabs in my opinion is too slow and too destructive in all but select circumstances. Lets say the first method found an area that for some reason was a jewelry hot spot. OK, now going deep based on acquired evidence makes sense.

A 3” x 18” coil is basically a 3” coil that is 18” long. It’s not an 18” coil that’s magically been made 3” wide while losing nothing in the process. Anyone expecting great depth needs to learn more about how coils work. This is very much a niche product. Again, this coil is for covering area fast while recovering shallow targets. If your goal is anything else, use a different coil.