PSN-L Message - Subject: Re: Seismograph for school

Hi John, Ted here, and I am one month into a similar project, using my = own money, for a non profit organization. We are having a lot of fun on the project, but the electronics are = challenging, even though I have worked on circuits, I thought I was up = to it electronic task, but now I am not sure. I have made some = progress however, so I think I am getting closer. I am happy to share my successes and failures if you would like to = correspond. Ted ----- Original Message -----=20 From: John Patskan=20 To: psn-l@................. Sent: Monday, September 25, 2006 11:11 PM Subject: Re: Seismograph for school Hello everyone, Thanks for the tips. I believe I will try to build the Lehaman style unit. This is actually an elementary school. It used to be an Environmental = Science magnet school, and they still have room they call the Eco-Lab. = Each class goes in there once a week and the teachers have them work on = some project. This year the teachers decided on a Geology theme. I = thought a seismograph would be nice to have in the lab. Actually I = think the homemade one would be better because the kids could get a = better idea of how it works. They wouldn't be doing anything in depth = but I thought seeing there own siesmograph records may spark some = interest in science. I Haven't approached the teachers yet as I want to = make sure I can pull it off first.=20 John P On 9/23/06, tchannel wrote: Hi Chris, What sort of "choice of suspension system" would you = recommend? Is there a detail I can look at?=20 I have only seen the knife edge style.=20 Thanks, Ted ----- Original Message -----=20 From: ChrisAtUpw@.......... To: psn-l@................. Sent: Saturday, September 23, 2006 5:09 PM Subject: Re: Seismograph for school=20 In a message dated 23/09/2006, jcpatskan@......... writes: I am thinking of trying to build a seismograph for my son's = school. I have quite a bit of experience in shallow exploration = geophysic's, mostly electrical and electromagnetic, but none in = seismology. I have searched the internet and found quite a few = resources.=20 Hi John, You might consider making a medium sized Lehman - about 2 ft = long? Say about 1.5 sec period that can be extended to 20 sec? You will need +/-12V stabilised power supplies of you may buy = an amplifier and transformer from Larry at http://psn.quake.net Since it will be used with other school systems, I suggest = that you use Amaseis and buy a DI-154 12 bit ADC still at just $39! = www.dataq.com Amaseis supports this ADC.=20 See http://jclahr.com/science/psn/as1/index.html Use magnetic damping, NOT oil.=20 Use an all metal braced single unit costruction - NO plastic = structural components - NO separated sections. Your choice of suspension system is critical. NEITHER a point = on a plane NOR knife edge systems are satisfactory - avoid them like the = plague. Most other systems are OK to good. You need to be able to get a = period of at least 20 seconds.=20 Have a look at = http://jclahr.com/science/psn/chapman/lehman/index.html=20 and http://jclahr.com/science/psn/chapman/index.html and http://www.jclahr.com/science/psn/cor_psn.html and http://jclahr.com/science/psn/ ALSO = http://www.mgm.monschau.de/seismic/english/artikel/artikel_1_4.php and = sequels I have also noticed a seismograph (or strong motion = accelerometer) on sale at e-bay, with an opening bid of $75. =20 I suggest that you forget this one! You do not need a strong = motion sensor - or the headaches of converting an optical one. This = might be called 'buying trouble'! Good Luck! Chris Chapman

Hi John, Ted here, and I am one = month into a=20 similar project, using my own money, for a non profit = organization.

We are having a lot of fun on the = project, but the=20 electronics are challenging, even though I have worked on circuits, I = thought I=20 was up to it electronic task, but now I am not sure. I have = made=20 some progress however, so I think I am getting closer.

I am happy to share my successes and = failures if=20 you would like to correspond. Ted

----- Original Message -----

From:=20 John=20 Patskan

To: psn-l@..............

Sent: Monday, September 25, = 2006 11:11=20 PM

Subject: Re: Seismograph for = school

Hello everyone,

Thanks for the tips.

I = believe I=20 will try to build the Lehaman style unit.

This is actually an=20 elementary school. It used to be an Environmental Science magnet = school,=20 and they still have room they call the Eco-Lab. Each class goes = in there=20 once a week and the teachers have them work on some project. = This year=20 the teachers decided on a Geology theme. I thought a seismograph = would=20 be nice to have in the lab. Actually I think the homemade one = would be=20 better because the kids could get a better idea of how it works. = They=20 wouldn't be doing anything in depth but I thought seeing there own = siesmograph=20 records may spark some interest in science. I Haven't approached = the=20 teachers yet as I want to make sure I can pull it off first. =

John=20 P

On 9/23/06, tchannel <tchannel@..............>=20 wrote:

Hi Chris, What sort of "choice of suspension system" = would you=20 recommend? Is there a detail I can look at?

I have only seen the knife edge style.

Thanks, Ted

----- Original Message ----- =

From: ChrisAtUpw@.......=20

To: psn-l@..............=20

Sent: Saturday, = September 23,=20 2006 5:09 PM

Subject: Re: = Seismograph for=20 school

In a message dated 23/09/2006, jcpatskan@............ writes:
I=20 am thinking of trying to build a seismograph for my son's = school. I=20 have quite a bit of experience in shallow exploration = geophysic's,=20 mostly electrical and electromagnetic, but none in seismology. = I=20 have searched the internet and found quite a few resources.=20

Hi John,

    You might consider making a medium = sized=20 Lehman - about 2 ft long? Say about 1.5 sec period that can be = extended to=20 20 sec?

    You will need +/-12V stabilised power = supplies of you may buy an amplifier and transformer from Larry at = http://psn.quake.net

    Since it will be used with other = school=20 systems, I suggest that you use Amaseis and = buy a=20 DI-154 12 bit ADC still at just $39! www.dataq.com = Amaseis=20 supports this ADC.

    See http://jclahr.com/science/psn/as1/index.html

    Use magnetic damping, NOT oil.

    Use an all metal braced single unit=20 costruction - NO plastic structural components - NO separated=20 sections.

    Your choice of suspension system is = critical.=20 NEITHER a point on a plane NOR knife edge systems are satisfactory = - avoid=20 them like the plague. Most other systems are OK to good. You need = to be=20 able to get a period of at least 20 seconds.

    Have a look at http://jclahr.com/science/psn/chapman/lehman/index.html=20

    and http://jclahr.com/science/psn/chapman/index.html
    and http://www.jclahr.com/science/psn/cor_psn.html

    and http://jclahr.com/science/psn/

    ALSO http://www.mgm.monschau.de/seismic/english/artikel/artike= l_1_4.php=20 and sequels

    I have also noticed a=20 seismograph (or strong motion accelerometer) = on sale=20 at e-bay, with an opening bid of $75.

    I suggest that you=20 forget this one! You do not need a strong = motion=20 sensor - or the headaches of converting an optical one. This might = be=20 called 'buying trouble'!

    Good Luck!

    Chris Chapman
=

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