On Sun, 4 Jan 1998 16:17:08 -0600 Martin McCormick
<martin@DC.CIS.OKSTATE.EDU> writes:
>        I believe that if the field switch was made during the
>vertical
>blanking interval, one would run the risk of loosing all the digital
>information such as VIR, Closed Captionning, Teletext ,etc

I think VCRs were invented well before that stuff was in widespread use.
Thinking about it some more, it would be important to have the vertical
sync pulses in phase with the rest of the field, i.e. switch heads before
the vertical sync pulse.  Otherwise the interlace wouldn't work properly
(not that it ever does).

>
>Martin McCormick
>