Got a new V3with some sort of coil problem.

[yazoo]

So I guess it be a toss up of some do some dont. Will have to check mine now ,just took it for granted .Yazoo

 

[yazoo]

I stand to correct myself, Looks like my 10x 12 SEF coil is V rated.I got a new camera I am trying to figure out 4 Xmas.So shot a couple of pics checking out the coil. So far 1 with a gold ring in analyze the other was In the house noise that disappeared for the most part as I dropped the RX to about 4. This was in best data.Then I tried 22.5 and got the high hump there also using my gold ring to pass over my coil.Looks like a new area of fun now. Yazoo

 

[Rob (IL)]

Yazoo, they don't list the 10x12 as V rated. If it was they wouldn't say so for sure. They do list the 6x8 as usable for the V3. The 10x12 would be the same as non V rated Whites coils, some will overload and some won't. If you could pick through a batch you would get one that works. Rob

 

[yazoo]

If not V rated then how is the 22.5 working. Yazoo

 

[yazoo]

Another thing comes to mind ,I got my coil about 3 weeks ago and the adEXcelerator Search Coils for White's

 

[Rob (IL)]

I wish they would say they were V nulled. We were using the SEF coils on the V3 before and they were not V rated. They worked but we couldn't run them to 15 in the air and them turn the TX on without them overloading. I would have thought when they could do this they would have made a big deal about it. They always worked with the 22 KHZ just not at the higher settings.

So you are saying the SEF can now be cranked up? Rob

 

[Larry (IL)]

The 10X12 EX I was using is well over two years old from the DFX days. It was made for 3 and 15 KHz and worked OK for me until I tried the Boost feature. That is when I got the overload when hunting in the ground. I didn't try the air test, but in my ground all the coils I tried resulted in overload on the ground. I have very mineralized ground.

 

[slumpshooter]

As the man said, the ads says they are V rated and my SEF 6 x 8 works just fine on high gain with TX boost on. While using these setting today, it worked well for about 30 min in my backyard. I I then experienced an overload indication for the first time, after resetting the unit it went back to working fine. My soil here in NC (at my house and generally area) is almost solid clay where this occurred. The sensitivity probe said I had 47% signal lose and 5% noise = a recommended recv gain setting of 5, I was running a recv gain of 15 w/TX Boost on at that time of that overload. I backed it down to 12 and left TX Boost on, all worked okay for rest of the afternoon... I have run this coil (SEF 6 x 8 ) in more friendly soil these past few days at full recv gain of 15 and TX boost on with no issues, i do not recall what my probe reading was at that time. I have only had this coil a week, I am still getting use to it. As near as I can tell it is excellent for working trash areas with very good performance on the V3, I have used the 10' D2 stock coil in the same area doing a direct comparison of performance and the D2 stock coil was more difficult finding desirable targets to dig, having to work around and separate out all the (and some times simultaneous) trash hits. The stock D2 coil is excellent in none trashy environments, and the coil of choice when working a low to no trash fields for me....

 

[yazoo]

My understanding on the coils so far is the10 dd is the only coil that is air tested to 15 RX to prove good.The other large coils from whites are not cranked as high to be with in the exceptable range.Is hard to test my 10x12 ex. in the house to the point of cranking it up to see this. I can use the TX boost at a low RX setting of 4 in house with a quiet screen and no chatter.I would think that being V nulled meant that it would hunt in the 22.5 freq. Other wise the old DFX coils would not need changed.So if the Ex coils are not V nulled to go inline with theV3 coils why are they advertised as for the V3? Is that not false representation ,implying something is made for but is not of the right specks? Yazoo

 

[Rob (IL)]

OK, first you are mistaken when you said, My understanding on the coils so far is the10 dd is the only coil that is air tested to 15 RX to prove good. All V rated coils can be turned up to RX15 with boost in the air. I've talked to Carl and Anne on this one. They all don't show a suggested RX of 15. Herre's a direct quote from Anne.

The best way to check your coil is to set your gain to 15, turn TX Boost on with the coil in the air (not on the ground or around other metal). If you don't get an overload, your coil is good. That is what the detector is designed for - not overloading at the extremes. The probe (zoom on the sensitivity live control) that suggests a recommended gain is not a good coil test.ak_1234

I'm not saying SEF coils don't work, they do. I'm just saying if they could all do the above test, I think Kellyco would say they are V nulled. I used Larry's 2 year old 10x12 and it worked fine. We just had to keep the RX lower and not try to use the boost.

I would think that being V nulled meant that it would hunt in the 22.5 freq No, It means it will do what Anne's above post said. Rob

 

[yazoo]

Ok So Be It. Thanks now I know a lil more. And with this said my super 12 that I bought from Whites should air test at 15RX with TX boost or it is bad? Could have swore though I read that some of the bigger coils would drift off speck and were considered good at a lower RX testing.




Yazoo

 

[Rob (IL)]

1 The suggested RX is not the test of a good coil, unless it gives an air test of less than 8. (suggested RX of . This is the specification you heard about. NOT ALL COILS GIVE A SUGGESTED RX OF 15. Suggested RX less than 8 gets you a replacement coil. A V nulled coil that gives a suggested RX of less than 15 will still not go into overload at RX 15 with boost in the air.

2 V nulled coils will not overload in the air at RX 15 (not suggested but real RX 15) with boost on. Turn the gain to 15, hold it in the the air, turn on boost, it shouldn't overload. You have a good coil. If it overloads you get another coil.

Suggested RX doesn't mean you can run it at the suggested RX. CAN you run your 10x12 in the air at 15 with the boost on without it overloading? If it won't it still doesn't mean the SEF wouldn't work fine. It just means it won't run this high. Rob

 

[yazoo]

Thinking I might have now absorbed the parts I was missing.And my deepest hunting coil is a non V rated coil is the 10x14 Excellerator.Havent got to try the SEF enuff to know much. Thanks Yazoo

 

[Rob (IL)]

Have a great day. If it works who cares. Get out there and get the good stuff. Rob

 

[yazoo]

Would love to but the lake out side of town is froze to about 9 inches ,so i doubt I could get much depth in my ground that was diggable.Yazoo

 

[slumpshooter]

That is really good info Rob, I assume it applies to all size coils? It would make sense that the bigger coils would be a little more unstable or less predictable in that warmer climates the expansion of so much copper wire could take it out of spec at least on 22.5Khz. I suppose that might be true if it is very cold as well. It would seem that the coil would perform best at the temperature it was made and nulled at. Not sure what the range or tolerance allowed or needed is at the time of test, but + & - range has to be a factor, to deal with extreme temperature variation and it's effect on the physical coil size. At the frequencies we are using with our V3s, 2.5Khz and 7.5 Khz would be easy to null for, as you get to higher frequencies like 22.5Khz the difference between 2.5khz and 22.5khz start to make that a little more difficult. Copper while being a great conductor, is one of the most reactive metals to temperature change, so you can be assured our coils will perform a little different in winter compared to those hot days of summer. Looks like our best days for optimum coil performance is what ever the temperature environment was at the time these coils are nulled, any body know the answer to that? Chris

 

[Rob (IL)]

They aren't going to overload if they are good, warm cold or in between. The small changes in the null won't affect the performance because it's purpose is the prevent the overload condition at the extremes. Remember, a coil with a suggested RX of 8 could still be run at 15 and probably still wouldn't overload.The choice of keeping the signal below 10 which the suggested RX was based on was an arbitrary factor which could have been higher with no performance effect. Rob

 

[CROCK of COINS]

Have a great day. If it works who cares. Get out there and get the good stuff. Rob

AMEN !
This is NOT rocket science. Just do it ;-)

Jerry