[Aavso-photometry] Monsoon shutdown for Wright28 and Wright 30

[Tom Krajci]

Monsoon is here in southern NM, and I've shut down the robotic scopes 
Wright28 and Wright30 for the season.

For a 'first observing season' attempt...I think they took some good 
data...mostly time-series stuff.

During monsoon I'll do maintenance and rework some things so that the 
images are sharper and I can work more crowded fields.

If anyone has a background in mechanical engineering...I need help with 
one project.  The 12-inch LX-200 is very underdamped on its fork.  I 
can't improve the bearing/stiffness in the polar axis without a major 
reworking of the mount...I won't do that.

However, I will try and find a way to use tuned dampers to help reduce 
vibration in breezy conditions.  I'm looking for some simple design 
rules of thumb to implement something like the Stockbridge 'dog bone 
dampers' described at:
http://en.wikipedia.org/wiki/Stockbridge_damper (specific design 
application)
http://en.wikipedia.org/wiki/Tuned_mass_damper (generic concepts)

It looks like the OTA/fork vibrates at about 10 - 20Hz (based on eyeball 
estimate)...so I need to have a tuned damper that absorbs a single 
frequency at around that value.

Thanks in advance.

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Tom Krajci
Cloudcroft, New Mexico
http://picasaweb.google.com/tom.krajci

Center for Backyard Astrophysics (CBA)
http://cbastro.org/ CBA New Mexico

American Association of Variable Star
Observers (AAVSO): KTC http://www.aavso.org/
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