Hi everyone,
If you want a vertical and more access to seeing the early
and clearer
"P" wave signals (and others), this might be the
machine for you.
Horizontals just don't pick up the early quake
signals quite as well.
With a adequate vault and temperature control, such a
instrument (at
least for here experience wise), will probably
prove to be very dependable
for low drift of the mass/boom.
The design came out in the 1950's-1960's
or thereabouts.
I'd suspect that the seller won't adequately prepare it for
shipment,
especially the boom/mass. When I got mine
(many years ago), the
pivot hinges were snapped, the cover viewing
glass was broken and all the
thin diameter jumper signal/damping
wires were broken. Relatively
minor items to replace/repair.
Their could be real serious reason for it
being surplus now (?).
Potentially the most serious/difficult problem "could" lie with the
two
coils for damping/signal. If they get thrown around and
damaged....their isn't any possible replacements. The
coil wire
it self can also break over time, due to a manufacturers
sudden coil
winding speed shift (a type of copper wire stress or
stretch knot),
which I've noted on acouple coils over time.
Luckily they were both on the
outside area of the coils, which
didn't mean too much unwinding too find.
Even in the worst case scenario (no working coils), the frame
and "zero
length" spring would be enviable to have; let alone the
longer period
vertical configuration. One "might" have to adopt
other
damping/signal means.
Note the weight of the unpacked instrument (115 pounds), the
shipping
cost can be potentially higher than the winning bid price.
On the other
hand, it "might" still be worthwhile to have even with
the tacked on
costs...the massive solid aluminum frame and parts
are usually excellent
material.
Be prepared to have to work on the brass setscrews (die), and
retap the
aluminum base setscrew holes due to oxidation, old
dried up
grease/dirt. The tap and die could cost up to $100,
or thereabouts.
If you win the bid, I'd suggest that the buyer request that the
two
mass weights be removed (unscrewed); the boom lock pin
installed, and the
coil magnets assembly also be removed (gently);
and shipped separately,
even if it means more cost initially to the
buyer. Otherwise; if you
can pick it up yourself, and prepare it
before moving....that would be the
best alternate route. The
risks and reward/s are with the buyer of
course.
Take care, Meredith
Larry Cochrane wrote:
Hi Everyone,
Someone on EBay is selling one. See
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=1785642626
I would bid on it but I don't need another sensor right now...
-Larry Cochrane
Redwood City, PSN