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Discussion Starter #1
as previously posted, i had a sort of banding, fabric-like texture overlay when using the s-video feed from source (dvd and sat) to AVP processor, through Leeza then rgbhv or DVI to pio 1000. it only occurred with s-video and seemed to be souce independent. I finally got rid of it by bypassing the AVP and feeding the sources directly to the Leeza. i was using two MIT S-Res cables, 2 meter and a generic s-video/bnc adapter and even tried swapping s-video cables to isolate a potentially bad cable


since the Leeza requires BNC inputs, i ordered a new s-video/bnc breakout and a straight s-video cable, silver serpents from Bettercables. I reinstalled the original path, including the AVP, and the PQ was excellent. Point being there was some mysterious negative synergy coming fom the s-video, cable type, AVP and Leeza used in various combinations.
 

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The LEEZA is very sensitive to impedance ratings (both input and output).


This is why they are using the BNC inputs for SVideo as well (to retain proper impendance matching, since Svideo is not usually very accurate). A problematic SVideo breakout could result in impendance related problems.


There was a similar problem with someone (sorry, I forgot who) who was having greenish tinted component outputs due to non 75 Ohm output impedance matching.


They never did quite explain how they did match impendances (e.g., splitting off like a Coax Ethernet connection), only that parts from RadioShack did the trick.


In my opinion, such a device should come with 1 or 2 such splitters, since SVideo sources are still all too common, but these breakout cables are not... Hopefully, KeyDigital will think the same on production run LEEZAs.
 

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Good point Ofer, but I don't believe this type of symptom (noise) is caused by an impedence mismatch. Usually you see things like ghosting, ringing, color bleeding and chrominance issues like you stated in your example.


This seems to me like a cable ground shield issue. Most higher end cables are directional because they use what is called a "drain" where they attach only one end of the ground shield on one end of the cable and the other is left unattached. This is similar to "lifting the ground" of a 3 prong AC plug, which eliminates noise on AC systems also.


I believe that maybe the new cables he used have this "drain" feature, thus eliminating the noise issue, probably induced in his AVP.


That's my half-hearted, uneducated guess anyway:rolleyes:!!!
 

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I was the one with the green tint. The fix that I applied (75ohm "F" connector terminator screwed on a BNC to "F" converter) fixes the green tint. However, it did not solve the problem 100%. I am still getting a problem with the picture (on passthru) that exhibits a darkness that comes and goes through the picture (perhaps described as color bleed and chrominance issues ?)


Don at Key Digital is sending me some different terminators and I am hoping they clear up the problem.


I actually have a catch 22 with my setup. (this will confuse you)


TV only accepts RGBHV.


On the LEEZA, if I passthru YPrPb to YPrPb and have an external converter convert the signal to RGBHV, the passthru picture is perfect. Unfortunately when using an SD input with this setup the picture has the same problem that JLM has described with the banding. If I leave the SD input alone and feed the TV output from LEEZA RGBHV directly, rather than the YPrPb thu the external RGBHV converter, then the SD picture is perfect. If I take my YPrPb signal and convert it to RGBHV and then feed it into the LEEZA for passthru to RGBHV the TV will not sync.


To summarize:


SD to RGBHV -> Perfect picture

SD to YPrPb to external YPrPb to RGBHV converter ->Fabric overlay picture

HD (YPrPb) to YPrPb to external YPrPb to RGBHV converter -> Perfect picture

HD (YPrPb) to RGBHV (LEEZA transcode) -> Color Bleed and Chrominace issues (as described by DHarp193)



So I'm hosed until I can find one way or another to get perfect picture from both SD and HD Passthru to RGBHV


I'm not complaining, but for the six grand I really shouldn't have these issues. (I guess I am complaining a bit...)


Also, maybe somebody has some ideas about my termination. I'm afraid that Don will send me terminators that won't be any better than what I cameup with, especially since I also tried just leaving the YPrPb output connected to my converter which should provide the proper 75 ohm load.


Thanks for listening
 

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Quote:
"sync on green"
I don't think either the TV (Mits WS65903) nor the LEEZA have the ability to set this. But I'm not 100% sure....


Steve
 

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I know the Mits does not have the capability to sync on green. However, I would look real hard at the Lezza manual. The more I read your post, the more I think Dave is on to something.
 

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Discussion Starter #8
i had the problem using all the mit s-video cables and the breakout and the avp; i didn't have the problem ditching the avp and using either s-vid cable and the breakout; i didn't have the problem ditching all the mit cables and the original breakout, but using the avp and the silver serpents.
 

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I'm confused (can you please list everything you tried, and what worked and what didn't)?


Is this what you have tried?

SD->LEEZA->RGBHV->Display

HD(YPbPr)->External transcoder (RGBHV)->LEEZA (HDTV bypass)->RGBHV output


As I understand it, the first option works ok. But the second gives you a problem.


Have you tried bypassing LEEZA and seeing if the first transcoder has a problem?


Does the LEEZA perform transcoding on the HDTV bypass circuit, when it runs to the RGBHV output?


As I understood it (take this with a big grain of salt), the only transcoding that's done in ONLY between the HDTV bypass and Component output!
 

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To summarize:


SD->LEEZA-> RGBHV = Perfect picture


SD ->LEEZA-> YPrPb ->External Converter-> RGBHV = Fabric overlay picture as describer by JLM


HD (YPrPb)->LEEZA -> YPrPb-> External->RGBHV converter = Perfect picture


HD (YPrPb) ->LEEZA->RGBHV = Color Bleed and Chrominace issues (as described by DHarp193)


HD(YPrPb)->External Converter->RGBHV->LEEZA->RGBHV = NoSync


HD(YPrPb)->External Converter->RGBHV=Perfect picture


These are the current combinations and results. Also have tried replacing cables and verified termination at 75ohms.


Regards,

Steve
 

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Discussion Starter #11
out of nowhere, my problem returned! i took the avp out of the link, and again, it went away. sounds like funky s-video switching in the avp.
 
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