PSN-L Email List Message

Subject: Re: Chapman's sensor Design
From: "Geoffrey" gmvoeth@...........
Date: Fri, 23 Jul 2010 08:58:15 -0700


It seems to me with a simple pendulum and a square coil
and 8 such magnets
one might make a two dimensional sensor in
the horizontal plane with but a single device ??

Looks very promising to me since I have
received wonderful signals in the past
from only one magnet and a solenoid like
coil fastened to the ground. All immersed
in synthetic oil.

I really want to get away from one direction only
thing sensors although it may make a quieter
sensor.

Two planes are fairly easy to handle at once
but all three it takes not less than
two separate devices.

Hasn't anyone ever ever tried to build a single
device to see any motion no matter the direction ?

In the language of the almighty patents,
Simply a Electric,Velocity Detector, Relative Motion, Pan-Dimensional, BlahBlahBlah
If you ever tried looking in a patent library you gotta learn their
peculiar way of labeling things.

Heck (80V/(in/sec)) looks kinda good to me.
That's the same as (3149.60629922 V/Meter/sec) ???
Not sure it works that way.

----- Original Message ----- 
From: "Bob McClure" 
To: 
Sent: Friday, July 23, 2010 7:26 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
>>
>>
>>
>
__________________________________________________________

Public Seismic Network Mailing List (PSN-L)


[ Top ] [ Back ] [ Home Page ]