[QuadList] Changes in Post over the years (wasElectronic Editing Notes)

[Bill Carpenter]

Don,

The flying erase head was added before the 7900, because I worked on the design on the 7800 and then tested it, and made good color edits. The circuity to drive the erase head was placed under the top transport trim, just  to the left of the scanner, between it and the supply reel. I remember changing the rotary transformer and get a signal that would turn it on to erase the video at the proper time.
I believe that this was done in late 1978, and we introduced it at NAB 79, in Washington.

Bill




________________________________
From: Don Norwood <dwnorwood at embarqmail.com>
To: videovault at sky.com; Quad List <quadlist at quadvideotapegroup.com>
Sent: Sat, January 30, 2010 1:02:58 PM
Subject: Re: [QuadList] Changes in Post over the years (wasElectronic Editing Notes)

 
Trevor:
 
The VPR-7900 which followed the 7800 by just a few years added a flying 
erase head, moved the dropout into the vertical interval, had an H-locked drum 
servo, and added Very High Band carrier mode which was identical to quad and 
then later to type-C format.  All of that allowed very high quality video 
and edits.  So while the 7800 had its limitations, it was a stepping stone 
in the development of helical during an era when many thought it could not be 
done.  Thanks to Bill and all who worked on those projects!
 
I still have a couple of 7900's.  Park has seen one of them and I 
think he would agree that the quality is quite good.  The transport design 
with the moving guides was the weak link, and that was addressed by the 
VPR-1.  
 
Don
 
----- Original Message ----- 
>From: Trevor Brown 
>
>
>Interesting 
>  Bill 
>I 
>  never saw anything but Push and Pray on VR 7800
>Insert 
>  3 second cycle out of edit was a problem for drop ins
>VR 
>  650 was worse with 7 seconds
> 
>Hated 
>  the VR 7800 machine format with its hole in the picture
>Thought 
>  IVC Alpha wrap was a better idea
>But 
>  I think it was several years later
> 


      
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