Why big coils and I are going our separate ways

[Tony]

What a difference 5" makes !!

I have been a Sovereign user for many years now and have now tried 3 large coils on my GT.

Big coils are severely hampered by EMI. So far, the SEF, WOT have failed in the EMI area. This is on beaches many miles apart and on many different times.

I am unable to have sensitivity hotter than 2 o'clock with the 15" coils which kills off the depth at the beach.
Big coils are just big antennas.

I can run my stock 10" with sensitivity at 9 o'clock AND Shaun's amp at full power
The detector does not false at all...the threshold is smooth as butter with all of this power !

I know it's EMI as I can point the coil to the sky and it falses big time...even on beaches 50 miles apart.

I have tried every setting......DISC......AM........Band 1 and 2. The big coils just will not work.
Remember, I have tried 3 different 15" coils with the same problems....weeks apart....beaches miles apart.

I'm able to get the magical 15" on clean targets (gold rings/clean coins) with the GT setup with stock 10" coil and Amped.

I posted some weeks ago that the WOT was fine but I realised that my settings were off.

In "AUTO" then things are quiet but there is no way I'm hunting beaches in AUTO as depth is hopeless.

Okay, these findings are for my local conditions so I know many of you will not have these problems.
Also, my beaches are like Florida beaches...very clean...no black sand. As posted earlier, pointing the coil to the sky gives the same falsing as on the sand.

Tony.

PS.....Just wanted to add this as well

>>> My PP mode is as deep as DISC but AM fixed (after tracking) is no where near as deep.

 

[Ron from Michigan]

Tony I agree the 10 inch Minelab coil for me works best.The Tornado 10 inch has given me the best performance of any coil I used HH Ron.

 

[Tony]

Amen to that Ron.

I will just use the bigger coils for recent/shallow drops during summer when I'm happy to run in AUTO.

I'm just staggered at the constant EMI problems with the 15" coils.....it's enough to drive one up the wall....

The 10" Tornado is brilliant....always.

Regards,
Tony.

 

[Bling]

of them i could not run sen above 2 Oclock i found with 4 S12's iv had all of them i could run around 10 Ok..i just ordered another S12 3 days ago!

 

[GunnarMN]

I noticed the same thing , the 15" coil is more efected by EMI but i still like it

 

[Neil]

I mostly beach hunt and the 10" sov and the 10X12 SEF coils are enough for me

 

[Tony]

Well at least I now know that it's just not me suffering from the EMI problems.

Thank you all for the replies that at least support my views on the significant EMI problems with the bigger coils.

Yes the ground coverage is great but the 15" isn't punching deep where the good stuff is buried.
By contrast, the 10" is an amazing coil.

Have a great summer everyone,

Tony.

 

[Critterhunter]

I've had less EMI problems with my 15x12 SEF than I did with my 10" Tornado, and I thought the 10" did well near electrical devices. Egg shaped or other "non-round" coils are said to be less prone to the 60khz of power lines and such from what I've read. All I know is I can hunt with the SEF at higher sensitivity settings at a few sites than I could with the 10", one place being a local fresh water beach.

 

[kered]

I think the factor here is Shaun's amp, i remember reading when he brought it out that it didn't like the bigger coils, but who needs them with the added depth to the stock coils

 

[Tony]

The EMI problem is still really bad with the Amp turned off.

It just goes to show how different beaches in different countries can present a totally different set of problems.

It shows that EMI comes in many different "flavours".......I guess the GT doesn't like the taste of some of them with certain coils....

These forums allow so much information with so many people each thinking they are "right" ......when they probably both are !!!!!!

Tony.