Hi all.

   I'm new to the group and just wanted to get my feet wet with a post, 
observations and some questions.  After many years of indecision, I finally 
made the plunge and built a Lehman.  It is currently operating in a crawl 
space under the family room.  I thought that it would be somewhat quiet 
there, but it seems that some poured concrete over dirt isn't that quiet.  
Additionally, I am 50 feet from a fairly busy road...but I'll take what I 
can get.
     With the help of Larry (very helpful and patient with questions), I got 
the electronics up and running and the rest of the story with pictures can 
be viewed at http://www.mckimzey.com/seismology.html     I haven't seen any 
activity yet, but did get a teaser with the recent Alaska quake...would have 
recorded it but that was the 12 hours that the system was down for some 
early modifications....hummf.

Right now I'm oil damped, but hope to make the metal damper.  I have seen 
that both copper and aluminum are used.  Is either better than the other?  I 
don't have ready access to copper plate (is it available at Home Depot or 
Lowes?) so I was going to use a pipe that I flattened.  What kind of 
thickness is needed?

I'm running WinSDR and I fiddled around with the gain on the board.  Is 
there a baseline count that I should aim for...I think that someone put it 
at around 100 or 200 (boy, that 4th quarter list archive was looong).  Also, 
does it matter if I display raw or filtered data?  I'm using the default 
WinSDR settings for alarms and filters.

Finally,  now that I've got the bug, of course I want more instruments.  I 
was thinking about the SG sensor, but the volksmeter has my interest piqued. 
  I heard that it might only be ready-made, but maybe it wouldn't be too 
difficult to build one.  The upright(s) of aluminum; shaft of aluminum 
(although the PDF looks like it was made of brass).  The plates could be 
made of PCB board, etched if needed.  It would just be the electronics that 
I would need to buy.  One of the things that I find neat about that design 
is that it probably could be minimized to a size where it could fit in a 6 
inch tube and be sunk several feet/meters in the ground (with remote motor 
leveling and such)

Ok, enough of my ideas.  My ignorance of seismology betrays me.  Any 
thoughts or ideas would be welcome.  Thanks!

- Mike


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