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<DIV>Don</DIV>
<DIV> </DIV>
<DIV>The AFC and Bare Bones DOC were included in all the machines at some point
in manufacture. The DOC was part of the AFC design. It was a freebie
as I put it. The RF signal that was inserted back into the picture
during a drop out was the frequency of blanking. This frequency was used
as it was the one that the AFC could clamp to a know point in the
video. Ampex did not use sync for a good reason. Sync levels varied
by a few between sources and thus with 100 IRE of video but different levels of
sync, the video level would change at the output of the de mod if you clamped at
sync tip prior to modulation.</DIV>
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<DIV>At least this is the way that I understood. Can someone verify this
or am I out to lunch on this theory?</DIV>
<DIV> </DIV>
<DIV>Chris Hill</DIV>
<DIV>WA8IGN</DIV></FONT></BODY></HTML>