Film-Tech Forum ARCHIVE: How to set phase without scope?

This is topic How to set phase without scope? in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Marin Zorica (Member # 1716) on 04-14-2006, 02:25 PM:

OK, I've been in couple of situation when i haven't scope and I have need to set phase on reader, and then i must run home to get scope.....it's OK if I wasn't 300Km from home [Big Grin]

I was thinking about connecting both channel (L

Posted by Pete Naples (Member # 761) on 04-15-2006, 01:18 AM:

Does your RTA have 'SUM' and/or 'DIFFERENCE' modes?

If so it's fairly easy. In SUM mode the trace shape shouldn't chnage and will rise up the display, assuming the Lt and Rt signals are in phase. In DIFFERENCE mode the tracw will fall, but again the trace shape should be similar to that of Lt or Rt. Out of phase signals will show as a dip or a bump in the trace.

In days gone by both focus and phase were set using 9kHz tone film, and adjusting for peak output. I don't know if you can get such tone film anymore.

Posted by Jack Ondracek (Member # 1466) on 04-15-2006, 03:23 AM:

By connecting the channels together and listening to the center channel monitor, you can get your reader pretty close... if you've got really good ears. Even then, you probably won't get it right on, but it'll be close enough for government work until you can get back there with a scope or RTA.

Remember, when adjusting it this way, you're listening for max highs.