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Re: [ARSCLIST] Wired: One Giant Screwup for Mankind



Ah - a slightly bigger project, but I still am sure the signal is very much alive and well. Getting a head stack may be some fun..... still there are several people who custom make them.



Jim Lindner

Email: jim@xxxxxxxxxxxxxxxxx

  Media Matters LLC.
  SAMMA Systems LLC.
  450 West 31st Street 4th Floor
  New York, N.Y. 10001

eFax (646) 349-4475
Mobile: (917) 945-2662
Office: (212) 268-5528

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Media Matters LLC. is a technical consultancy specializing in archival audio and video material. We provide advice and analysis, to media archives that apply the beneficial advances in technology to collection management.


www.sammasystems.com
SAMMA Systems provides tools and products that implement and optimize the advances in modern technology with established media preservation and access practices.



On Jan 11, 2007, at 12:03 PM, Richard L. Hess wrote:


Hi, Jim,

I am pretty sure that there is no RF. It would be called "FM" but I'm 97% sure that these are "Direct" or AM instrumentation recordings, not FM as the bandwidth generally wouldn't be available in FM. It's 500 kHz bandwidth on the tape -- and I mis-spoke. Two adjacent pixels going from black to white is a half cycle, not a full cycle, so 500 kHz is the system bandwidth, assuming square pixels of a 320 line 10 fps (assuming progressive) video signal.

Hopefully, there is a timecode (IRIG probably) on the tape that could be used as a control track for flutter compensation/time base correction.

Remember, this is video, but not recorded on a video tape recorder. Other channels presumably record medical telemetry. Larry Miller on the Ampex list worked on instrumentation recorders and indicated that they were sold in the multiple 100s of thousands of dollars in the 1960s...they were essentially one-offs and very high tech.

Cheers,

Richard

Cheers,

Richard



At 11:46 AM 2007-01-11, Jim Lindner wrote:
I think that putting together a one off machine with a phase locked
loop would be pretty straight forward - but rather then even worry
about that - I would just pull the data off and do a "virtual" tbc of
it in software. IF there is some sort of control track pulse it would
be very simple, correction of timing error in software would be
pretty straight forward to  interpolate. In the article (and others)
there is this persistent discussion of them "fading away"... this it
unlikely  - IF they can find the tapes - it is likely that they were
reasonably high coercivity so the RF carrier may be a bit weaker -
but probably still more then good enough to read - particularly
considering some of the head technology that exists these days.
Probably not a small project - - but this is a very "do-able"
one....... of course finding tapes is a pre-requisite. What surprises
me - is the general surprise that they were "lost" in the first
place. This is a recurring theme for decades now - and I fear it will
be repeated for many more....



Jim Lindner

Email: jim@xxxxxxxxxxxxxxxxx

  Media Matters LLC.
  SAMMA Systems LLC.
  450 West 31st Street 4th Floor
  New York, N.Y. 10001

eFax (646) 349-4475
Mobile: (917) 945-2662
Office: (212) 268-5528

www.media-matters.net
Media Matters LLC. is a technical consultancy specializing in
archival audio and video material. We provide advice and analysis, to
media archives that apply the beneficial advances in technology to
collection management.

www.sammasystems.com
SAMMA Systems provides tools and products that implement and optimize
the advances in modern technology with established media preservation
and access practices.


On Jan 10, 2007, at 11:17 AM, Richard L. Hess wrote:


Wired Magazine has written about the lost Apollo 11 tapes -- again.
Still not found.

This is a good summary, though the last several paragraphs repeat
at the end.

http://www.wired.com/wired/archive/15.01/nasa.html

This would most likely be an Ampex instrumentation recorder.

It would take some work, and the timebase would be less stable, but
these tapes could probably be played on a cobbled-together system
using an audio recorder. The timebase stability of the Ampex
instrumentation recorders was better since the heads were right at
the capstan (which was grooved).

Cheers,

Richard

Richard L. Hess email: richard@xxxxxxxxxxxxxxx
Aurora, Ontario, Canada (905) 713 6733 1-877-TAPE-FIX
Detailed contact information: http://www.richardhess.com/tape/ contact.htm
Quality tape transfers -- even from hard-to-play tapes.


Richard L. Hess email: richard@xxxxxxxxxxxxxxx
Aurora, Ontario, Canada (905) 713 6733 1-877-TAPE-FIX
Detailed contact information: http://www.richardhess.com/tape/ contact.htm
Quality tape transfers -- even from hard-to-play tapes.


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