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Detector Technology and Electronics and new detectors => Detector Coils => Topic started by: Doug on Thursday September 27 2018 12:33:46 AEST PM



Title: The "Bismark" coil
Post by: Doug on Thursday September 27 2018 12:33:46 AEST PM
https://www.youtube.com/watch?time_continue=114&v=ND6dPRv1JnE
link-https://www.youtube.com/watch?time_continue=114&v=ND6dPRv1JnE
I wonder how it would run on the QED?
doug ::419::


Title: Re: The "Bismark" coil
Post by: Doug on Friday September 28 2018 12:05:47 AEST PM
  
https://www.youtube.com/watch?time_continue=114&v=ND6dPRv1JnE
link-https://www.youtube.com/watch?time_continue=114&v=ND6dPRv1JnE
I wonder how it would run on the QED?
doug ::419::

I wonder where the Bismark coil is now?
doug ::419::


Title: Re: The "Bismark" coil
Post by: jrbeatty on Friday September 28 2018 18:05:04 AEST PM
Not sure Doug. Robyn sold/gave away a lot of Jim's gear.

Here's John Hider Smiths 36" flat wound in action which Reg Wilson now owns:

https://youtu.be/v21liiSdLrM (https://youtu.be/v21liiSdLrM)


Title: Re: The "Bismark" coil
Post by: Doug on Friday September 28 2018 19:35:21 AEST PM
  
Not sure Doug. Robyn sold/gave away a lot of Jim's gear.

Here's John Hider Smiths 36" flat wound in action which Reg Wilson now owns:

https://youtu.be/v21liiSdLrM (https://youtu.be/v21liiSdLrM)

Did   John Hider Smith  make the coil?
doug ::419::


Title: Re: The "Bismark" coil
Post by: jrbeatty on Saturday September 29 2018 15:46:30 AEST PM
Yes Doug. He had technical help with the winding from a friend whose name escapes me, and he did the glassing himself. I remember him demonstrating its robustness by driving over it with his ute, much to Jim Stewarts horror - - - ::620::
Reg now owns it and has run it on his kwed successfully.  ::419::


Title: Re: The "Bismark" coil
Post by: Doug on Tuesday October 16 2018 10:51:08 AEDT AM
The Bismark in action.
https://www.youtube.com/watch?time_continue=45&v=5yQlkb-aesg
doug ::419::


Title: Re: The "Bismark" coil
Post by: jrbeatty on Tuesday October 16 2018 11:24:02 AEDT AM
Jim wound the "Bismarck" with a slightly higher than normal impedance, which meant it took awhile to stabilise when first switched on, but Jim theorised that this could have given it better than normal depth for a coil of this size.

Th "Bismarck" and the carrier I built for it now resides with Jims widow Robyn.


Title: Re: The "Bismark" coil
Post by: Doug on Tuesday October 16 2018 11:32:43 AEDT AM
  
Jim wound the "Bismarck" with a slightly higher than normal impedance, which meant it took awhile to stabilise when first switched on, but Jim theorised that this could have given it better than normal depth for a coil of this size.

Th "Bismarck" and the carrier I built for it now resides with Jims widow Robyn.

Jim wound another 24" mono i believe?
doug ::419::


Title: Re: The "Bismark" coil
Post by: jrbeatty on Tuesday October 16 2018 15:08:37 AEDT PM
Jimmy wound a lot of coils. Biggest I remember was a 48" mono but it was totally impractical. He had a number of coils in the 24" size, including some wound earlier for "Whites" detectors.
Bismarck was the only 36" mono he had for many years, but we modified a 36" DD which we had made to order by John Gladdis and John Kah at Coiltek, after a similar sized coil we made produced unimpressive performance (as did theirs)

Towards the end of his life Jimmy and Tony Honey made several experimental "concentric" coils as well as experimenting with Ground loops.
Tony has carried on with Jims coil making legacy and, working in communication with Rohan Johnson (Nuggetfinder) has made several large loops of many configurations. The most impressive are the concentrics, which blow monoloops out of the water on depth in extreme (or any) ground.


Title: Re: The "Bismark" coil
Post by: GARY on Tuesday October 16 2018 16:20:16 AEDT PM
  
The most impressive are the concentrics, which blow monoloops out of the water on depth in extreme (or any) ground.

I would agree on some results I have been privy too view using extreme timings.

Gary.


Title: Re: The "Bismark" coil
Post by: Doug on Tuesday October 16 2018 22:13:12 AEDT PM
 When i last met Jim he was winding up a large coaxial coplanar coil using litz wire. I wonder if he ever finished the coil before he got ill?
doug ::419::


Title: Re: The "Bismark" coil
Post by: jrbeatty on Wednesday October 17 2018 08:06:26 AEDT AM
That's the type I'm referring to.  ::419::

Tony and Jim worked closely together developing this type of coil and Tony has continued developing and refining them following Jims demise.
That particular coil was not a complete success but by altering the winding layout and inner/outer coil spacing ratios Tony has now several working coils of different diameters. Here's one:

(http://i67.tinypic.com/2us8zgo.jpg)

We tested several at the Laanecoorie test site last year using different sized gold and, as I said, they have about 15-20% depth advantage over a similar sized flat wound monoloop. No extreme settings were used.

Tony has also considered non co-planar concentrics, or "Top Hat" configurations but is yet to produce a working prototype.


Title: Re: The "Bismark" coil
Post by: GARY on Wednesday October 17 2018 10:49:54 AEDT AM
What I call as an extreme setting is in Normal timing using a mono coil over high mineralised ground.


Title: Re: The "Bismark" coil
Post by: jrbeatty on Friday October 19 2018 21:13:54 AEDT PM
  
What I call as an extreme setting is in Normal timing using a mono coil over high mineralised ground.

Just back home from a Colonoscopy examination in Canberra. 

Hi Gary. My favourite Minelab extreme setting was using a big double "D" in "Sharp" It worked for me!  ::419::

 The advantage of the "concentric" type above is its unsurpassed ability to penetrate extremely hot ground. Tony relates how (in the west some years back) using a 5000 and jackhammer, he recovered a 14 oz colour buried deeply in solid ironstone.
This piece gave a good signal. He told me that no other coil he tried over it could hear anything. With just my short time testing them, I believe him.
 
 Because the coaxial co-planar layout has a deep, well focused but narrow conical field, it has maximum depth, but it is easy to miss targets without good overlap. Incidentally, Tony informs me that he has no need for a GPZ 7000.  ::419::



Title: Re: The "Bismark" coil
Post by: GARY on Saturday November 3 2018 18:01:03 AEDT PM
  

Just back home from a Colonoscopy examination in Canberra. 

Hi Gary. My favourite Minelab extreme setting was using a big double "D" in "Sharp" It worked for me!  ::419::

 The advantage of the "concentric" type above is its unsurpassed ability to penetrate extremely hot ground. Tony relates how (in the west some years back) using a 5000 and jackhammer, he recovered a 14 oz colour buried deeply in solid ironstone.
This piece gave a good signal. He told me that no other coil he tried over it could hear anything. With just my short time testing them, I believe him.
 
 Because the coaxial co-planar layout has a deep, well focused but narrow conical field, it has maximum depth, but it is easy to miss targets without good overlap. Incidentally, Tony informs me that he has no need for a GPZ 7000.  ::419::


G'day JRB, only just read your reply today since I've been away on a trip to Japan however good to be back in Oz.

Btw do you know what timing Tony was using on the 5000 with the "concentric" type coil to recover the 14ozer buried deep in ironstone?

Gary.


Title: Re: The "Bismark" coil
Post by: jrbeatty on Saturday November 3 2018 18:39:38 AEDT PM
Gary:

Don't recall the timing used. If you're ever near Laanecoorie, call in at the park for a chat with him.

I've known Tony for years. Jim Stewart and I were always impressed with the quantity of big gold he recovered from north west WA following up after cyclones.

Here's another shot (upside down sorry  ::419::)

(http://i63.tinypic.com/vy6qa9.jpg)


Title: Re: The "Bismark" coil
Post by: bugwhiskers on Sunday November 4 2018 15:23:22 AEDT PM
The post below dates back to May 2012.
It's interesting to note that since then at least 2 parties have lodged patents that feature "constant current damping".


Title: Re: The "Bismark" coil
Post by: jrbeatty on Sunday November 4 2018 15:44:06 AEDT PM
Can't comment on the technical side personally since I haven't used ground loops but, once again, Jim and Tony were working on them when Jim died. Although depths obtained were super impressive, stability was unsatisfactory and Tony lacks the electronic knowledge to pursue the experiment any further:

(http://i63.tinypic.com/4hz24h.jpg)

We all know somebody here with the requisite knowledge to take the idea further - - -  ::62::


Title: Re: The "Bismark" coil
Post by: bugwhiskers on Sunday November 4 2018 16:48:28 AEDT PM
IBgold, Muntari and Aziz have been making progress but obtaining the raw materials is difficult.


Title: Re: The "Bismark" coil
Post by: IBGold on Sunday November 4 2018 16:52:25 AEDT PM
Hi I will attach some pictures of the six foot ground loop and TX unit that was designed about four years ago to be used with the QED as the driver and as the RX unit but went no further due to medical problems at the time and due now to my detecting partner and I being in our 70's not being able to dig the deep holes needed but if one of you wants to carry on with the project talk to me.

Regards, Ian. ::62::