18"@2,7 kHz ("Uber Howitzer") Coil

Discussion in 'Coils Fitting Single Frequency AKA Metal Detectors' started by SuchMuch, Jan 8, 2016.

  1. SuchMuch

    SuchMuch Administrator Staff Member

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    I have already mentioned this coil in thread "Hunting For High Conductors (Large Objects) with AKA detectors"

    18"@2,7 kHz ("Uber Howitzer")
    18_inch_coil.jpg
    Above image represents AKA Signum MFT equipped with 18 inch coil running 2,7 kHz

    This is a special task coil and the deepest one on large objects among all AKA coil range. It will miss coins and sometimes it can pick up large coin close to surface. Detectorists hunting for relics like Roman helmets, daggers, swords will benefit from the coil. There were attempts to produce 18" coil with different low frequencies (E.g.: 18"@1,5 kHz etc) and frequency 2,7 kHz was found to be the best one with optimum depth/sensitivity parameters for 18" size.

    It's not an easy task to produce electro-mechanical stable coil in such a size especially for metal detectors working in resonance (AKA Signum MFT, Signum MFD) and when AKA is overhelmed with orders, they can delay the production of these coils. If you are planning to have this coil, the best time to place special order with AKA is autumn/winter time.

    No doubt this is the deepest coil ever produced for DEEP mode (Signum MFD).
    Happy hoard hunting ;)
     
    Last edited: Feb 1, 2019
    Avci1455 likes this.
  2. mschmahl

    mschmahl "AKA Deutschland" Group Moderator Staff Member Supporter

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    Wow, what a big thing.
    Do you have some ideas about the price of this coil?
     
  3. TS
    TS
    SuchMuch

    SuchMuch Administrator Staff Member

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    I have no idea about the price. It's a very special task coil should it be used in VLF mode, but I think it could be valuable one within DEEP mode (AKA Signum MFD) on large objects.
     
  4. mschmahl

    mschmahl "AKA Deutschland" Group Moderator Staff Member Supporter

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    But the coil looks interesting. First I have to test the Deep Mode, maybe the coil will be my birthday-present than.
     
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    TS
    SuchMuch

    SuchMuch Administrator Staff Member

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    There are some rumors AKA no longer produce these coils...
     
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    SuchMuch

    SuchMuch Administrator Staff Member

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    Well, AKA can produce these coils but avoids doing that :Negative:. On the one hand we (detectorists) understand that it's a not a simple task to produce electromechanical stable coil in this size and amount of non stable coils increases when 18" coils are produced (AKA utilizes non stable coils as defect ones instead of NEL, for instance), but on the other hand this coil could be needed in some circumstances, rarely but needed.

    Top AKA tester's post translation:
    ***qte***
    I've produced 18" DD@3F (1,5 kHz, 3,5 kHz, 6,5 kHz) just to find out what benefits this size and aforementioned frequencies could bring. I have used copper wire since there is no space for aluminium wire in press form for frequency 1,5 kHz. As results coil is extremely heavy (1250 grams including cable weight), but bungee support does the job.

    5 kopecks Ekaterina 2 hits VDI +64 (SuchMuch's remark: This coin usually hits +84, +86 with low frequencies in size 13" / 15"). Frankly speaking, I cannot predict final result, I'll be testing the coil. At least ground and hot rocks / cold rocks could be suppressed (could it be valuable in mountains?) without missing large solid conductive objects at the same time I think so...

    ***
    5 Kopecks Ekaterina 2
    full.jpg
    Diameter: 41,5 mm
    Weight: 51,2 grams
    Material: copper
    Type: high conductor
    Remarks: one of the largest coins ever issued in Russia
    ***
    It would be really interesting to try 25" DD @1,5 kHz with turbo mode switched on o_O
    ***unqte***
     
  7. StiV

    StiV AKA Europe AKA Supplier Supporter AKA Intronika

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    Also recently available and 18 "/ 3kHz coil for deep searching:
    AKA_18inch_Coil.jpg
     
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    SuchMuch

    SuchMuch Administrator Staff Member

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    Good news! Is it 2,7 kHz or 3 kHz?