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<DIV>George</DIV>
<DIV> </DIV>
<DIV>Interesting that CBS would try to turn the capstan. The diameter was
set for monochrome standard at 60 Hz. The color standard is 59.94
Hz. This is less than 1 one hundredth of a percent difference. The
size of the capstan determines the length of tape that is pulled through per
revolution. </DIV>
<DIV> </DIV>
<DIV>The SMPTE RP for the layout of tracks on the tape is what is critical for
interchange. There has to be the correct distance between tracks.
The angle of the track from vertical. The distance from the track to the
position of the control track head. The placement of the Vertical sync on
the tape with the frame pulse. Even the distance to the erase and audio
heads. There is a shape that is required called the canoe.</DIV>
<DIV> </DIV>
<DIV>Fortunately there is enough slop in the servos to take into account the
miniscule difference in the master sync generators used during record and
playback. Think of video tape as a mechanical frame sync. Because
the capstan and heads compare the off tape sync to the house sync they will
adjust the speed to compensate. </DIV>
<DIV> </DIV>
<DIV>Regarding the capstan belt. I have never had to replace one.
The never broke on the machines that I had. I did look at one when
the capstan was pulled and I took the cover off just to see it. I did
replace the capstan motors on an AVR 2 that was damaged in a fire so that was an
easy fix. We thought about rebuilding the shafts but found out that the
diameter was so critical we could only buy new. </DIV>
<DIV> </DIV>
<DIV>Chris Hill</DIV>
<DIV>WA8IGN</DIV></FONT></BODY></HTML>