In a message dated 2006/11/06, sophie@.................. writes:

> Sophie here again,
> Thank you for all the replies to my last question, I've had an
> interesting weekend looking at loads of information. I know all about
> the BGS as dad works there and his best friend runs the Monserrat
> Volcano Observatory where I got interesed in seismology.
> I think I have decided on this sensor:
> http://www.fairpoint.net/~sparksite/CSpring%20Seismometer.html as dad
> says he has all the bits to make it and most of the BGS sites seem to
> use vertical component sensors. 

Hi Sophie,

       This older version uses oil damping and does not have a hinge mec
hanism to prevent side to side oscillations. You won't get much sensitivity for the 
very long period Rayleigh waves. Send an EMail to Roger asking for updates? I 
think that Roger now uses Magnet + Plate damping. If not, I can provide your 
dad with suggestions for doing this. You will find oil damping difficult to 
set up correctly, very temperature sensitive and seriously messy. You need to 
damp this sort of sensor both vertically and horizontally. It is not as easy / 
simple as it looks. Buy fully hard hacksaw blades (NOT the ordinary ones) and 
get your dad to grind the teeth and bends right off. Otherwise the blades will 
be noisy and crack in service. A rather better spring system still uses two 
blades, but set at a V angle to stiffen it for side to side motion.
  
Also these electronics: > http://www.infiltec.com/seismo/inf-qm10.htm , dad 
> says he is out of practice at making electronic things so we better buy some! 
> We have an
> old pentium 3 laptop that will collect the data and dad says he knows
> ways of using our home network and internet time services to keep the
> time on it correct to within a few hundreths of a second.
> Does this look an OK way to start a seismology hobby station? I can see
> lots more I can do later but that looks a quick, easy way to get going.

       There is a reference to time servers on the John Lahr's website. Many 
commercial ones suffer from digital transmission delays, which can be seconds 
at peak periods.

       Chris Chapman (in the UK)
In a me=
ssage dated 2006/11/06, sophie@.................. writes:



Sophie here again,

Thank you for all the replies to my last question, I've had an

interesting weekend looking at loads of information. I know all about

the BGS as dad works there and his best friend runs the Monserrat

Volcano Observatory where I got interesed in seismology.

I think I have decided on this sensor:

http://www.fairpoint.net/~sparksite/CSpring%20Seismometer.html as dad

says he has all the bits to make it and most of the BGS sites seem to

use vertical component sensors. 




Hi Sophie,



       This older version uses oil damping and=
 does not have a hinge mechanism to prevent side to side oscillations. You w=
on't get much sensitivity for the very long period Rayleigh waves. Send an E=
Mail to Roger asking for updates? I think that Roger now uses Magnet + Plate=
 damping. If not, I can provide your dad with suggestions for doing this. Yo=
u will find oil damping difficult to set up correctly, very temperature sens=
itive and seriously messy. You need to damp this sort of sensor both vertica=
lly and horizontally. It is not as easy / simple as it looks. Buy fully hard=
 hacksaw blades (NOT the ordinary ones) and get your dad to grind the teeth=20=
and bends right off. Otherwise the blades will be noisy and crack in service=
.. A rather better spring system still uses two blades, but set at a V angle=20=
to stiffen it for side to side motion.

  

Also these electronics: 
http://=
www.infiltec.com/seismo/inf-qm10.htm , dad says he is out of practice at mak=
ing electronic things so we better buy some! We have an

old pentium 3 laptop that will collect the data and dad says he knows

ways of using our home network and internet time services to keep the

time on it correct to within a few hundreths of a second.

Does this look an OK way to start a seismology hobby station? I can see

lots more I can do later but that looks a quick, easy way to get going.



       There is a reference to time servers on=
 the John Lahr's website. Many commercial ones suffer from digital transmiss=
ion delays, which can be seconds at peak periods.



       Chris Chapman (in the UK)