Du fragst nach einem in deutschland sehr selten angebotenen gerät .... wenn du das nötige kleingeld hast, guck auf ebay ....
um den richtigen schaft zu ordern, guck in diesem ebayshop und frag den verkäufer direkt.
der verkäufer igor ist auch gleichzeit bei AKA Russland der Mann fürs Export Geschäft. er kann alle AKA zubehörteile beschaffen inkl. spulensonderanfertigungen (z.b. 13" 1.5khz , 13" 18khz , 9.5"x12.5" 20khz, oder die 3-Frequenz spulen usw ....)
der ebayverkäufer heisst garyman2008 , einfach mit der ebaysuche nach verkäufer suchen.
ausserdem gibts für den AKA signum eine neue Firmware um tiefe , nichteisen objekte auf stark eisenverseuchtem boden mit geringer mineralisation besser zu erkennen , der neue Suchalgorythmus heisst "deep mode"

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das teil heisst AKA Signum MFD.
hier der kommentar vom chefentwickler Lvovich :
Let me translate post of top AKA tester regarding DEEP program and its benefits:
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As per Lvovich DEEP program is designed to detect LARGE objects under iron cover (small participles like nails etc) with 15” coils. DEEP algorithm is a substitute to TM808 and equal detectors but with ability to identify metal type (iron/non ferrous) in case of good signal strength. Your Signum MFT could be turned into deep scanning detector and restored back as a VLF detector just in 1 click – this could be useful when target needs rechecking.
There is another way you can use DEEP program with any coil of any size when you cannot keep coil close enough to the ground (long grass, very thick leaves layer , snow layer) and in cases when keeping high clearance between coil and ground is a necessity (rough plough, conductive/salty grounds, enormous amount if hot rocks). Some targets will not be separated from iron but hunting will be without falsings and with better target identification. Depth will be almost the same Signum usually has at yr grounds. Using DEEP program this way is subject to further tests.
If yr grounds aren’t mineralized and aren’t conductive average/big coins could be picked up at great depths.
We tested 5 kopecks (copper coin with diameter 42-43 mm and weight 51 gram) at Moscow grounds (red loams) at depth 50 cms and Signum failed to detect the coin in VLF mode and in DEEP mode too.
Detector succeed identifying 5 kopecks buried at depth 30 cms with small iron nail above in DEEP mode and produced straight hodograph line in copper zone, when we switched detector into VLF mode, it failed to identify the coin with small iron laying above as non-ferrous object.
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