Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!munnari.oz.au!bruce!trlluna!rhea!aduncan
From: aduncan@rhea.trl.oz (Allan Duncan)
Newsgroups: comp.sys.amiga.hardware
Subject: Re: 1950 vertical jitter
Message-ID: <2348@trlluna.trl.oz>
Date: 15 Oct 90 22:40:14 GMT
References: <3996@rorschach.oakhill.UUCP>
Sender: news@trlluna.trl.oz
Lines: 25

From article <3996@rorschach.oakhill.UUCP>, by eric@oakhill.UUCP (Eric Quintana):
> *
> 
> I'm experiencing a vertical jitter problem with my 1950 moniter
> (attached to my A3000).  The entire screen jitters a one scan
> line distance.
> 
> I believe that the problem is in the moniter itself.  Adjusting
> the de-interlacer has no effect.  (I'm using one of the Hires-interlaced
> modes with the de-interlacer on.)

From a sample of one, the 1950 seems to have a vertical oscillator
stability problem.  If you feed it an interlaced signal, look closely
(magnifying glass may be necessary) and see if the alternate fields
are properly interleaved.  Without a CRO to check the video, I can't be
sure that the 3000 is playing the game wrt equalizing pulses etc in the
vertical sync block.  When you ask the monitor to display 600 lines on
one scan, you need a _very_ stable oscillator or it will jitter.  From
the number of comments that I have heard on this topic, I think the 1950
fails the test.

Allan Duncan	ACSnet	a.duncan@trl.oz
(03) 541 6708	ARPA	a.duncan%trl.oz.au@uunet.uu.net
		UUCP	{uunet,hplabs,ukc}!munnari!trl.oz!a.duncan
Telecom Research Labs, PO Box 249, Clayton, Victoria, 3168, Australia.