MarsMD has released a new coil – 7 DD. It’s the round sniper small-sized versatile one for different search tasks – while dealing with high-trash areas, sweeping the attics, basements, hunting on beaches or around the rocks, as well as in harsh and electrically noisy environments, where other coils won’t be able to work.
MarsMD 7 DD coil. Shape: round. Type: DD. Completely waterproof. Weight: 370 grams (a minimum one, it may vary for different metal detectors. Comes supplied with a coil bolt.
All content related to the new coil will be collected here. You’ll be able to find additional info about the MarsMD 7 DD on Knowledgebase pages soon (e.g., the list of compatible metal detectors).
WATCHING NOW
Already to have it at home …
Can you translate this phrase into English? (Joke.)
I have two coils from Mars for my Garrett Ace Euro & Raider MD6250 –
Mars Sniper 6×10″ DD and Mars Tiger 10×13″ DD. Their operation is more
stable than “original” 8.5×11″ DD coil from Garrett. There is “big secret”
in these coils – they have “built in” “passive amplifier” practically it is
LC-filter inside the coil that cut off low frequency noise so the coils are
quiet. When Mars 7″ DD coil will be available I will take one.
Also I expect Mars 11″ DD round coil for Ace/Raider. I believe that combination
of 7″ DD coil and 11″ DD coil will work miracles!
I made a snapshot of my RTG discovery but I do not see the amplifier there
The “passive amplifier” is used only in Ace/Raider coils.
I guess it was the first MD they made the coil for.
At first they used capacitor in parallel to Rx coil to make
resonance LC network. It was good only for Ace 150/250
as Ace 350/400 has different frequency. Now they use
680nF capacitor in series with Rx coil and such coils work
well with all Garrett series – Ace 150/200/250/300/350/400.
This idea could be borrowed from Garrett AT Pro it has
470nF capacitor in series with Rx coil but this cap is placed
on PCB not in the coil itself. The difference between “standard”
Garrett coils and Mars/NEL coil you can see if you use ohmmeter
to test coils – Garrett coils show low resistance on both Tx and Rx
sides and Mars/NEL only on Tx side on Rx side they show 680nF
capacitance if you use RLC-meter.
Theoretically “passive amplifier” could be made for other types of
metal detectors but it need “some brain”.
P.S. There is a “tip” from a man whose nick is “sv-coil” he recommend
to place 680nF capacitor in series with Rx coil on standard Garrett
coils for Ace and place this cap into connector. I am goin to try it!
ET thanks for the explanation
P.P.S. If you look at the picture above better you can see that Tx
coil is wrapped by litz it consists of several thin wires. If I guess right
it was made to increase Q of Tx. On the other hand Rx coil is wrapped
using single wire so it has low Q. I wander what metal detector this coil
is made for? And how look the original coil for this metal detector?
Is there any “noticible” difference between these coils?
Image stretched I do not know why. RTG coil belong to E-trac
So my guess-work was right! Safari/Explorer/E-Trac coils
are wrapped using litz! I think that from the point of view of
theory the so called “passive amplifier” could be built into
E-Trac coil but the price of such coil will be comparable
with the price of E-Trac.
Fantastic coil !