I too have taken a look at dealing with the UK
and it the customs people who are the
unreasonable interferences here.
They, I think, Want you to lie to get
things through because if you lie
it is at their discretion they have the
freedom to do stuff. If you lie and
they do nothing then you know you are
just little fish whom they care
nothing about. I think unless
you are a zillionaire not a good idea
to deal with things directly from
other countries when transfer
of goods are involved.
If you are 100% truthful and pay what all
those ridiculous middlemen (crooks) want
you will pay many times more than the thing
is worth in actual fairness.



----- Original Message ----- 
From: "GPayton" 
To: 
Sent: Friday, July 23, 2010 9:46 AM
Subject: Re: Chapman's sensor Design


> Thank you Kay & Bob.  Both have been very helpful.
> 
> I've ordered the 38 ga.wire and glass epoxy unclad PCB to make the coil.
> 
> After checking into the cost of the SEP sensor from the UK, and (estimating 
> the possible weight) estimating the shipping from the UK to me in Texas; it 
> would be almost $700 US dollars!  OUCH
> 
> If they read the PSN site: I wished they would get a U.S. distributer. I 
> know they would benefit in sales.
> 
> So, I am going to try to build one of this type.  I might say that I tried 
> in the 2008-9 period, before moving to Texas.  I do not have near the 
> facilities or tools available now that I did then.  (Say a prayer for me.) 
> It is going to be difficult.  However, my alternatives are few.
> 
> Bob, I guess that I am a maverick.  In looking at these various designs and 
> drawings, I can't help but wonder about possible modifications.  For 
> instance, the number of turns in a coil.  To me, for a given amount of gauss 
> increasing the number of turns cutting the flux, the angle that they cut and 
> the speed determine the output voltage.  So, following drawings EXACTLY may 
> be a matter of choice.  The amplification of that output is a factor too.
> 
> Enough of my soapbox speech.  I appreciate everyone's input, and I am sure 
> it helpful for other novices too.
> 
> Best Regards,
> Jerry
> 
> --------------------------------------------------------------------------------
> 
> 
>  ----- Original Message ----- 
>  From: Bob McClure
>  To: psn-l@..............
>  Sent: Friday, July 23, 2010 9:26 AM
>  Subject: Re: Chapman's sensor Design
> 
> 
>  I prefer the following block magnets:
> 
>  http://www.gaussboys.com/ndfeb-magnets/B5012.html
>  Model: B5012
>  Size:  50mm long x 25mm wide x 12mm thick
>  Price: $11.00 each
> 
>  An assembly of two quarter-inch thick steel plates, four magnets, and a 
> one-quarter inch gap will yield a field of almost 7,500 gauss. A rectangular 
> coil of 1100 turns of #38 wire will yield an output of ~80 volts per meter 
> per second. The coil resistance is only 340 ohms, and you can easily use 
> resistive shunt damping with negligible loss of output.
> 
>  See: http://sites.google.com/site/bobmcclure90/horiz
> 
>  Bob
> 
> 
>  On Thu, Jul 22, 2010 at 11:46 PM, Kay Wyatt  wrote:
> 
>    Jerry,
>    they are magnitized through the thickness.  I order mine through K&J 
> Magnetics at http://www.kjmagnetics.com
>    The part number is
>          BX0X02
> 
>    1" x 1" x 1/8" thick
>    Grade N42 - Nickel Plated
>    Magnetized thru Thickness
> 
>    Hope this helps.
>    Kay
> 
> 
> 
>      ----- Original Message ----- 
>      From: GPayton
>      To: psn-l@..............
>      Sent: Thursday, July 22, 2010 8:30 PM
>      Subject: Chapman's sensor Design
> 
> 
> 
>      Looking closely at the drawings on this page, I am not certain about 
> the magnetization of the required sets of magnets.  Are they magnetized from 
> end-to-end or through the thickness?
> 
>      Most magnets I have found online, so far, have been through the 
> thickness, but I am not sure what is shown on the drawing.  Anyone know?
>      Thanks,
>      Jerry
> 
> --------------------------------------------------------------------------
> 
> 
>        Here is the link to Chris Chapman's coil design and instructions
>        http://www.jclahr.com/science/psn/chapman/lehman/index.html
> 
> 
>
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