Overload and 14kHz coil

Discussion in 'Coils Fitting Single Frequency AKA Metal Detectors' started by Seppo H, May 15, 2019.

  1. Seppo H

    Seppo H AKA Novice

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    Hey! I bought a used 14kHz coil manufactured by Aka but it may have a problem. I have tried all possible ways, but the coil operates normally only when the gain is less than 5. If you adjust the gain 5 or more overload occurs. Is this normal or is the coil defective? My other coils have no such problem.
     
  2. SuchMuch

    SuchMuch Administrator Staff Member

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    Make "wet hand" and "shake" tests
     
  3. TS
    TS
    Seppo H

    Seppo H AKA Novice

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    I did the tests and the coil passed them. The coil is very stable when the gain is set to 4. When the gain is 5 it will not work at all. Maybe there is something wrong with the connector, because if I touch the coil cable near the connector, the device reacts strongly to it. Can I check the coil cable by measuring the resistance between its wires?
     
  4. Ethane

    Ethane Dutch Throll

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    Are you inside or near any big metal parts?

    Otherwise if you just bought it you can contact your suplier and send it in if possible to let it check
     
  5. SuchMuch

    SuchMuch Administrator Staff Member

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    Probably the reason of that is connection. @StiV @mschmahl will share their experience with fixing connector plug.

    Meanwhile pls clean pins of the connector like it said in thread: "How to Keep AKA Coils' Connectors Clean" and and thread: "Problem with coils "overload""
     
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  6. TS
    TS
    Seppo H

    Seppo H AKA Novice

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    I tried it in the forest so no interference there. Bought it as used from eBay.
    Edit: I got an agreement with the seller to return the coil. Must buy a new one on next time.
     
    Last edited: May 15, 2019
  7. TS
    TS
    Seppo H

    Seppo H AKA Novice

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    I changed my mind, after all, when I got some of my money back. Coil is mine now. I opened the connector and cut 5cm from the cable and soldered the wires back into the connector. But the repair was not helpful. The device works the same way as before:Cray:Here's a video about how the device works:
     
  8. mschmahl

    mschmahl "AKA Deutschland" Group Moderator Staff Member Supporter

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    I don´t think it is the cable or connector, because the overload comes without touching the cable. Maybe you have some metal in or on the coil or a metal bolt to fix the coil to the stem?
    Maybe the shielding around the lower end of the coilwire is broken. Can you do a good GB with this coil?
     
  9. pasadete

    pasadete AKA Veteran

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    Most cable breaks occur where the cable meets the coil
    --- Double Post Merged, May 19, 2019, Original Post Date: May 19, 2019 ---


    It would be interesting to know the value in ohms of each of the two coils, that data is known by AKA
     
  10. TS
    TS
    Seppo H

    Seppo H AKA Novice

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    There is no metal near the coil. And yes I manage to do ground balance when gain is less than 5 and economy mode is on. Something goes wrong when power increases.
     
  11. SuchMuch

    SuchMuch Administrator Staff Member

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