Date: Sat, 18 Apr 2009 11:24:20 -0700
From: hilpert at cs.ubc.ca
To: General at invalid.domain
Subject: Re: 1966 Lunar Orbiter image tapes rescued in LA Times: via AmpexFR-900
Pontus Pihlgren wrote:
John Foust wrote:
Are these the same tapes mentioned here?
http://thinkingshift.wordpress.com/2007/07/27/the-curious-case-of-lost-nasa…
Pretty awesome though, that lady Evans is a real hero!
Looked like a really fun project to work on. I like the picture of the
sleeping
bag laid out amidst the stacks of tapes in the "recovery laboratory"
(abandoned
McDonalds restaurant).
There was some mention of the analog tape format but I wish there had been a
little more technical write-up of the old equipment and the transfer process
and issues they went through.
The lunar orbiter missing tapes story is not nearly as interesting as the LOST lunar
landing tapes in the thinkingshift link above.
They still have not found these - the images were much better that what we saw.
A little surfing turned up the lunar camera manual:
http://radsite.lbl.gov/radiance/refer/Notes/gamma.html
The TV telemetry and communications documents are here:
http://www.hq.nasa.gov/alsj/alsj-TVDocs.html
I worked on these recorders - I did moon quake data reduction (Apollo ALSEP) for the
University of Texas when NASA shifted priorities to Skylab. The nuclear powered
seismometers were all still functioning and sending live data. NASA had no use for them
anymore, so we took over. The recording/playback machines were called 'Wideband
Instrumentation Recorders' and handled analog data up to 500KHz or so. They recorded
in both FM and direct (baseband) modes. The recording was of course a digital one, and we
recovered the data and transcribed it to digital 7 track on a PDP 15.
We plotted the seismic data on Versatec electrostatic 'wet' type printers.
Whenever we were plotting, and we came upon an 'event' either a moonquake or a
meteor strike, the geophysics guys had a field day. On one occasion, NASA crashed the
spent SIV-B stage into the moon, just to see what happened. The moon is solid, a crystal
and no molten core. Following the impact, it 'rang like a bell' for almost an
hour. We got the bright idea to speed it up a bit, D/A convert it and listen. Id did
indeed sound like a bell... well more like a cymbal crash.
Randy
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