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Internal Virus Database is out-of-date.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
Hi Dale, I went to this wed site but =
could not see=20
your article, do you have another source?
Thanks, Ted
----- Original Message -----
From:=20
Dale Hardy=20
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@............ =
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 Effect=20
Magnetic field detector chip ht=
tp://www.allegromicro.com/en/Products/Design/an/an27701.pdf
I see one chip can determined =
direction. X=20
and Y? If this is so, is there a way =
to apply=20
that directional information to trip a relay or otherwise light a =
series of=20
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 1884=20
Part 2
In a=20
message dated 2008/03/17, tchannel1@............=20
writes:
But how would one record the pendulum direction of =
movement?=20
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 the=20
penduum, a lamp and four photocells. Either of these could =
give you=20
the X and Y sensitivities.
=
Or make=20
it to the design and accept that it is not a very sensitive =
device. Maybe=20
put a flat on the top of the pendulum and set a ball bearing on =
the flat?=20
This 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