[QuadList] Quad wasn't the only NTSC recording medium used for Apollo flights

[Ted Langdell]

Here's a link to the 2006 NASA article about the search for the  
missing data tapes, and the preservation of the equipment to play them.

http://www.nasa.gov/mission_pages/apollo/apollo_tapes.html

Basic summary and side notes:
Because of power limitations, Apollo 11 used specially developed slow- 
scan video that had to be converted into a format that could be  
broadcast over commercial television. The original signal was  
transmitted at 10 frames per second in one field and had to be  
converted to 30 frames per second in two fields to be viewed on your  
TV set.

The signal originated on the Moon, traveled through the emptiness of  
space back to Earth, and was received by tracking stations on the  
ground in Goldstone, California; Parkes, Australia; and Honeysuckle  
Creek, Australia. These three tracking stations recorded the original  
signal that included the television video, as well as voice,  
telemetry, and biomedical data. The data was recorded onto magnetic  
tapes, and simultaneously converted into a U.S. broadcast format for  
transmission to Houston and final release to U.S. television networks.
----
(TL notes: The conversion was done by using a long-persistence picture  
tube to display the slow scan images, which were shot by an RCA TK-22  
vidicon camera.  A disk recorder was used to create enough fields to  
work with the NTSC signal.

Read more here: http://www.parkes.atnf.csiro.au/news_events/apollo11/tv_from_moon.html

Photo of Honeysuckle Creek scan converter: http://www.honeysucklecreek.net/images/ed_von_r_tv1.jpg

---
The equipment used to convert the signal unfortunately caused some  
unavoidable loss of image quality.

The dark-looking images are due—in part—to using a gamma of 1.0 in the  
camera. That choice was made to preserve the option for post-facto  
processing of 1200+ scan-line pictures the camera could produce in  
case film-based photos weren't possible.

See comparions of the Slow scan monitor images and NTSC pictures here: http://www.parkes.atnf.csiro.au/news_events/apollo11/Parkes_Apollo11_TV_quality.html

and here:
http://www.honeysucklecreek.net/Apollo_11/index.html

(Click on the links as necessary)

Stills here: http://www.honeysucklecreek.net/Apollo_11_EVA_stills/index.html

The Scan converter operator at Honeysuckle shot Super8 footage of both  
the slow-scan and NTSC monitors during the moonwalk. Interesting  
differences.

The footage has been used to make two DVD's about the station's  
activities.

The Parkes video signal was what was used for most of the TV coverage.

Ampex VR-660 2" helical recorders were used to record the NTSC- 
converted Parkes signal in Sydney.

Some very good photos of the other Australian station—Honeysuckle Creek 
—show the 2" Quad recorder used there, backed by Ampex VR-660's.

See photos here: http://www.honeysucklecreek.net/station/video.html

The NASA webpage on the data tape search reports:
First-generation copies of the converted video from Apollo 11 as well  
as other first-generation copies and some original versions of the  
converted video for the Apollo 12 through Apollo 17 flights are still  
in NASA Johnson Space Center's Informational Resources Directorate's  
video vault in Houston.

So it is possible that the enhanced video being showcased on Thursday  
came from two different 2" formats: Quad and VR-660 Helical.

Yet to be rediscovered:
The telemetry signals (including the SSTV video) were recorded onto  
what the Parkes link says were 1/2" tapes mounted on Mincom M22  
instrumentation recorders.

The NASA webpage about the preserved data equipment and the  
Honeysuckle website say they were one-inch tapes.  Goldstone used  
Ampex FR-1400's according to the Honeysuckle Creek website.

The telemetry tapes are what is being sought, in the hope that modern  
digital processing will yield even better images from the 320 line  
Slow Scan data.

Especially if gamma correction were applied.

Ted

Ted Langdell
Secretary
Skype: 	TedLangdell
e-mail:	ted at quadvideotapegroup.com

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