Re: SRSG timing light

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Michael Rhodes by way of Terry Fritz <twftesla-at-qwest-dot-net>" <rhodes-at-fnrf.science.cmu.ac.th>

The vertical sweep rate of TVs is 60Hz/50Hz and the horizontal sweep
rate is 15,750Hz (an even multiple of the 60Hz).  A complete frame is
built (interlaced) through 2 cycles (30Hz).  Frame rates of >= 24 comes
from the mechanics of the eye in integrating the image.  Slower then this
one will see flicker.  Of course some of the integration is handled by
phosphor persistance and as such lower rates can be used, but this was
mostly with Oscopes (P4 phosphors).  The 60Hz vertical sweep rate
is historical in nature. That is it was a frequency that was readily
available (power line) and  very stable and essentially a free frequency
reference thus cutting the costs of TV construction.  Picked this info
up while working repairing TV sets as a student in college
(actually I started repairing TV sets for the neighborhood when I
was in high school - business picked up after starting to run my TC:-).

Of course new TVs now are crystal controlled but the frame references
are still the same.

--Michael

> >
> > Original poster: "Mike Novak by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<
> > acmnovak-at-msn-dot-com>
> >
> > Hello All,
> > I've been away for quite some time.. my comp crashed bigtime...
> > Anyway, as I was walking down the hall in my house, I glanced past a fan
> > which was in the line of sight of the TV. The blades' shadows moved
slowly
> > like an async motor under a timing strobe. I was thinking " if the TV
> > frequency was an even 60Hz, one could use it to phase in a SRSG...
> > particularly, one with a clear rotor. "
> > If this is insane or has already been discovered, lemme know...
> >
> > -Mike
>