Searching for SMPTE standard for Ampex Type A format video recording--The rest of the story--

[Ted Langdell]

This topic has appeared on the QuadList and OldVTRs via several different subject lines over the years. 

Back on Dec. 1, 2014, I asked the QuadList and Old VTRs to help shed light on the subject:  Searching for SMPTE standard for Ampex Type A format video recording


There were a number of responses, including links to SMPTE material online, some of which has been repeated in the current threads.

http://mail.quadvideotapegroup.com/pipermail/quadlist_quadvideotapegroup.com/2014-December/date.html

That prompted further research.

After finding and posting links to what I found on the SMPTE website, I followed up... with people who I expected would know the answers or where to find them. 

Apparently, I got busy, and didn't post the results:  

I did ask Fred Remley—SMPTE's Co Chair of the committee dealing with standardization of One Inch Helical Videotape Recording Systems—to try to shed some light on the Ampex 1" format(s) and whether the "Type A" proposed standard was ever adopted as such. 

Fred Remley replied:

Re: Questions regarding National Standardization of One Inch Helical Videotape Recording Systems--

...Here is my preliminary response: there is no SMPTE Type A 1in. helical standard. 

Your research shows that the Type B and Type C standards prevailed. Type B was a German proposal, as noted. Type C represents the result of long discussions between Ampex, Sony, and broadcasters/production houses. The audio specs were especailly difficult to agree upon and finally resulted in a wonderful compromise between the equipment manufacturers. 

I believe that Type A in SMPTE work was a priority designator only, with no real technical meaning. The first standard proposal for a given purpose was often called Type A. More complex designations seem to prevail today! Alex Alden, whom you quote below, is likely responsible for the designations, in actual fact. He was a very organized and overall excellent SMPTE Staff Engineer.

There are couple of other people who may have comments and  I’ll try to contact them.

Thanks  for the excellent research you’ve done! Brings back memories…mostly good!

    Fred 

Fred asked Dave Fibush to comment and bring some first-person knowledge to the foreground. Fred noted:

> Dave worked for Ampex for many years and was their participant in the Type C deliberations. He later worked for Tektronix.

Dave advised Fred:
 

> 12-04-14 
> 
> Hi Fred,
> 
> Its good to hear from you. . . . . 
> 
> As for Type A format(s) I only know about the one that was supposed to be the original Ampex 1-inch format. When we started to document the Type B and C formats it was agreed that the format used on the VPR-1 and several earlier Ampex 1-inch helical VTRs could be documented as the 1-inch Type A format. As my draft of the Type C format was nearing completion I use the same documents, with modifications, to define the Type A format. As I was working on the specification for the track recorded on tape I asked Dick Hathaway for the details. He answered "What year?". The track for the VPR-1 was well defined but never clearly defined for older VTRs hence the well known interchange problems. So Ampex decided to not submit a Type A format for standardization.


I highlight again what Dave wrote:

> So Ampex decided to not submit a Type A format for standardization.



> Do you remember that the Type C format was agreed in principal at the O'Hare Hilton on 7/7/77? I an earlier meeting CBS (Bill Connelly?) said they would never play a tape with part of the vertical interval missing (Ampex implementation with no sync head). I asked if they would refuse to play an Ampex tape showing the first extraterrestrial landing on earth. End of discussion.
> 
> Regards,
> 
> Dave


Dave advised several days later:

> Ted,

> 

> You are welcome to use my comments. 

> 

> As I remember the main compromise was that Ampex agreed there would be an optional vertical sync head and recording and Sony agreed to move the entrance and exit guides to the close spacing required for our operation without the sync head. I distinctly remember we had a backup plan for that meeting if they didn't agree but I have no idea what it was :-)

> 

> Regards,

> 

> Dave


From these comments, one can conclude that there is no Ampex Type A SMPTE Standard, but the parameters have been memorialized within SMPTE documentation. 

The recent thread on OldVTRs about the Ampex 1" format that lead to the proposed 1" Type A standard has drawn out a lot of useful information about the format, and how it changed over the years.

Thanks for all the contributions. 


Ted

Ted Langdell
Secretary
Quad Videotape Group
e-mail:	ted at quadvideotapegroup.com

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