eric@oakhill.UUCP (Eric Quintana) (10/12/90)
* 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.) The worst part of this problem is that it comes and goes. I would like to see the problem get worse before I try to show it to my dealer. (These things always seem to work fine near a repairman.) Does anyone have an idea how to fix this? I have no qualms with opening up the moniter and adjusting it myself. Any help is appreciated. This problem is reducing my productivity on the 040. :-) Eric Quintana eric@rorschach.sps.mot.com
jil@cs.iastate.edu (James Lathrop) (10/13/90)
eric@oakhill.UUCP (Eric Quintana) writes: >* >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.) >The worst part of this problem is that it comes and goes. >I would like to see the problem get worse before I try to show >it to my dealer. (These things always seem to work fine near >a repairman.) >Does anyone have an idea how to fix this? I have no qualms with >opening up the moniter and adjusting it myself. >Any help is appreciated. This problem is reducing my productivity >on the 040. :-) >Eric Quintana eric@rorschach.sps.mot.com I have had and still have the same problem. I took it back to the dealer when I received it. Unfortunatley there eyes are not as good as mine and they didn't have time to wait 15 minutes for it to start jittering. The bottom line was that they couldn't do anything unless they saw that something was wrong. I connected my 3000 to a NEC-3D and there was no problem. I was able to stop the jitter by making the top scanline visable at the top of the screen. I also think that it depends on your background color. If anyone knows how to fix this problem please post. It is extreamly frustrating! Jim Lathrop jil@atanasoff.cs.iastate.edu
aduncan@rhea.trl.oz (Allan Duncan) (10/16/90)
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.
eric@oakhill.UUCP (Eric Quintana) (10/18/90)
* As an originator of this thread, let me try to stave some of the 1950 monitor flaming. I have solved the vertical jitter problem (I think). In a nutshell, I opened up the moniter and made an internal adjustment. The screen has been rock solid ever since. But before I post what I did, I am waiting a few days to see if the jitter ever comes back. If this solves the problem, you can rest easier knowing that the 1950 is not inherently bad, it's just out of adjustment. It is annoying that Commodore is shipping them this way. Finally, let me state that I actually *like* my 1950. (The vertical jitter is the only problem I have seen, and once solved, it looks like a good choice to me.) Eric Quintana eric@rorschach.sps.mot.com
steve@cpoint.clearpoint.com (Stephen Steir) (10/18/90)
In article <4042@rorschach.oakhill.UUCP> eric@rorschach.UUCP (Eric Quintana) writes: >As an originator of this thread, let me try to stave some of the >1950 monitor flaming. > >I have solved the vertical jitter problem (I think). > >Eric Quintana eric@rorschach.sps.mot.com I wish my 1950s only jittered. The first monitor made a large snap sound causing the screen to shrink by about 25%. The second monitor had no picture at all and made a high pitched whistling noise (I am told that this is a bad flyback transformer). Whether your monitor jitters or has a bad flyback transformer, it's Commodore QC that needs adjustment! Until an adjustment is made, I think I'll try some other monitors. ------------------------------------------------------------------------------ Steve Steir - Clearpoint Research Corp., 35 Parkwood Dr., Hopkinton, Ma. 01748 UUCP: steve@frog!cpoint ATT: (508) 435-2000 BIX: clearpoint ------------------------------------------------------------------------------
aduncan@rhea.trl.oz (Allan Duncan) (10/29/90)
From article <4042@rorschach.oakhill.UUCP>, by eric@oakhill.UUCP (Eric Quintana): > As an originator of this thread, let me try to stave some of the > 1950 monitor flaming. > > I have solved the vertical jitter problem (I think). > In a nutshell, I opened up the moniter and made an internal adjustment. Does the interlaced scan work correctly with the new settings? By this, I mean that the odd and even scans are evenly placed above/below each other, rather than having two lines close together, then a slight gap to the next pair. 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.