Hi Ted,
it is not my article, just a link, did you scroll down to APRIL 2004 =
Experimental Seismograph Logger ?=20
just rechecked, you have to buy the back issue sadly.........
Dale
----- Original Message -----=20
From: tchannel1@...............
To: psn-l@.................
Sent: Thursday, March 20, 2008 10:37 AM
Subject: Re: Scientific American 1884 Part 2
Hi Dale, I went to this wed site but could not see your article, do =
you have another source?
Thanks, Ted
----- Original Message -----=20
From: Dale Hardy=20
To: psn-l@.................
Sent: Wednesday, March 19, 2008 5:18 PM
Subject: Re: Scientific American 1884 Part 2
Hi Ted,=20
I built a vertical based on a Honeywell Hall Effect sensor SS495A. =
It worked quite well at the time. EPE online magazine had an article in =
April 2004 for a vertical using the SS495A
http://www.epemag.wimborne.co.uk/projects2004.html
Dale
----- Original Message -----=20
From: tchannel1@...............
To: psn-l@.................
Sent: Tuesday, March 18, 2008 10:43 AM
Subject: Re: Scientific American 1884 Part 2
Hi Chris, Is this the type of Hall Effect Magnetic field detector =
chip http://www.allegromicro.com/en/Products/Design/an/an27701.pdf
I see one chip can determined direction. X and Y? If this is =
so, is there a way to apply that directional information to trip a relay =
or otherwise light a series of LED's
They look inexpensive, $2, so if not one, we could use several, =
(8) to form a compass.
Thanks, Ted
----- Original Message -----=20
From: ChrisAtUpw@..........
To: psn-l@.................
Sent: Monday, March 17, 2008 4:37 PM
Subject: Re: Scientific American 1884 Part 2
In a message dated 2008/03/17, tchannel1@............ writes:
But how would one record the pendulum direction of movement?=20
Hi Ted,
If you want tthe system to work for small quakes, use =
either a vertical magnet and two pairs of Hall Effect Magnetic field =
detector chips or use a disk on the end of the penduum, a lamp and four =
photocells. Either of these could give you the X and Y sensitivities.
Or make it to the design and accept that it is not a very =
sensitive device. Maybe put a flat on the top of the pendulum and set a =
ball bearing on the flat? This might give appreciable sensitivity?
Regards,
=20
Chris Chapman=20
-------------------------------------------------------------------------=
-
Internal Virus Database is out-of-date.
Checked by AVG.=20
Version: 7.5.519 / Virus Database: 269.21.7 - Release Date: =
8/03/2008 12:00 AM
-------------------------------------------------------------------------=
-----
Internal Virus Database is out-of-date.
Checked by AVG.=20
Version: 7.5.519 / Virus Database: 269.21.7 - Release Date: 8/03/2008 =
12:00 AM
Hi Ted,
it is not my article, just a link, did =
you scroll=20
down to APRIL 2004 Experimental=20
Seismograph Logger ?
just rechecked, you have to buy the =
back issue=20
sadly.........
Dale
----- Original Message -----
From:=20
tchannel1@............ =
Sent: Thursday, March 20, 2008 =
10:37=20
AM
Subject: Re: Scientific =
American 1884=20
Part 2
Hi Dale, I went to this wed site but =
could not=20
see your article, do you have another source?
Thanks, Ted
----- Original Message -----
From:=20
Dale=20
Hardy
Sent: Wednesday, March 19, =
2008 5:18=20
PM
Subject: Re: Scientific =
American 1884=20
Part 2
Hi Ted,
I built a vertical based on a =
Honeywell Hall=20
Effect sensor SS495A. It worked quite well at the time. EPE online =
magazine=20
had an article in April 2004 for a vertical using the =
SS495A
http://www.ep=
emag.wimborne.co.uk/projects2004.html
Dale
----- Original Message ----- =
From:=20
tchannel1@............ =
To: psn-l@.............. =
Sent: Tuesday, March 18, =
2008 10:43=20
AM
Subject: Re: Scientific =
American 1884=20
Part 2
Hi Chris, Is this the type =
of Hall=20
Effect Magnetic field detector chip ht=
tp://www.allegromicro.com/en/Products/Design/an/an27701.pdf
I see one chip can determined=20
direction. X and Y? If this is =
so, is=20
there a way to apply that directional information to trip a relay =
or=20
otherwise light a series of LED's
They look inexpensive, $2, so if =
not one, we=20
could use several, (8) to form a compass.
Thanks, Ted
----- Original Message ----- =
From:=20
ChrisAtUpw@.......
To: psn-l@.............. =
Sent: Monday, March 17, =
2008 4:37=20
PM
Subject: Re: Scientific =
American=20
1884 Part 2
In a=20
message dated 2008/03/17, tchannel1@............=20
writes:
But how would one record the pendulum direction of =
movement?
Hi=20
Ted,
If you want =
tthe system=20
to work for small quakes, use either a vertical magnet and two =
pairs of=20
Hall Effect Magnetic field detector chips or use a disk on the =
end of=20
the penduum, a lamp and four photocells. Either of these =
could=20
give you the X and Y=20
sensitivities.
Or make =
it to the=20
design and accept that it is not a very sensitive device. Maybe =
put a=20
flat on the top of the pendulum and set a ball bearing on the =
flat? This=20
might give appreciable=20
sensitivity?
=20
Regards,
=20
Chris Chapman=20
Internal Virus Database is out-of-date.
Checked by AVG.=20
Version: 7.5.519 / Virus Database: 269.21.7 - Release Date: =
8/03/2008=20
12:00 AM
Internal Virus Database is out-of-date.
Checked by AVG. =
Version:=20
7.5.519 / Virus Database: 269.21.7 - Release Date: 8/03/2008 12:00=20
AM