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Discussion Starter #1
As the title suggests do any of you know the max horizontal frequency these tv's can scan at?


The reason I ask is because I have the Australian PAL equiv. the KVHR36M31, and here our 720p standard is 50hz(unlike US where it is 60), which means it requires 35Khz to run in 720p.
 

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You will have to rely on the spec's or contact the manufacturer. The stated input formats/resolutions directly imply respective horizontal scan frequencies as stated above. Some TV's can sync. to the input and accept "in between" scan frequencies, most cannot.


When discussing scan frequency on CRT's or in analog video signals you need to include the scan lines in the vertical retrace interval which contains 30 additional scan lines for 720p giving a frame total of 750. So the scan frequency for [email protected] is 37.5 KHz rather than the 35 KHz you stated. The "frame" total for 1080i is 1125.


Video hints:
http://members.aol.com/ajaynejr/video.htm
 

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Quote from a Sony DA-4 Chassis Troubleshooting Manual, Video Processing Chapter: "All video processing is performed on the B-board (DRC and MID processing). The DRC circuit will double the horizontal frequency for input signals with 15.75KHz (NTSC) horizontal inputs.

The MID circuit will up-convert the horizontal frequency of the input signal to 33.75KHz, which is the scan rate of the DA-4 and DA-4X chassis. Table 5-2 shows the signal standard and its associate horizontal frequency.


Table 5-2 - Input Signal Standard and Horizontal Frequency

Input Signal Horizontal Frequency

Standard NTSC 480i 15.534KHz

High Resolution 480p 31.5KHz

High Resolution 720p 45KHz

High Resolution 1080i 33.75KHz


The following is a description of the signal flow for each standard listed in Table 5-2:

· 15.734KHz input: DRC circuit up-converts to 31.5KHz and MID circuit up-converters to 33.75KHz

· 31.5KHz input: MID circuit up-converts to 33.75KHz

· 33.75KHz input: XBR, HV pass through MID; HS bypass MID circuit

· 45KHz input: MID circuit down-converts to 33.75KHz


The output of the MID circuit is then applied to the CRT drive..."


The tv scans at a fixed horizontal scan rate of 1125*60Hz/2 = 33.75KHz, NTSC and likely 1125*50Hz/2 = 28.125KHz, PAL.
 

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I still think it's rather intruiging that, a few months ago, I connected my PC to the XBR960 via HDMI/DVI.


I had the VGA connection going from the PC to my LCD PC monitor so I could keep control over things.


To my amazement, I had a choice of refresh rates all the way up to 85Hz, REGARDLESS of what resolution I choose. And it worked!


Now, the question I still haven't answered all the way is this: Did the XBR960 actually display something at 85Hz, or does the TV force everything down to 60Hz regardless?


Make sense?
 

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as I said when I pmed you Q, that was only because you were using clone mode

and yes the refresh were reduced so it could be displayed on your TV


if you ran the two monitors in dual mode, then you would not be able to set the XBR at 85Hz

Quote:
Quote from a Sony DA-4 Chassis Troubleshooting Manual, Video Processing Chapter: "All video processing is performed on the B-board (DRC and MID processing). The DRC circuit will double the horizontal frequency for input signals with 15.75KHz (NTSC) horizontal inputs.

The MID circuit will up-convert the horizontal frequency of the input signal to 33.75KHz, which is the scan rate of the DA-4 and DA-4X chassis. Table 5-2 shows the signal standard and its associate horizontal frequency.


Table 5-2 - Input Signal Standard and Horizontal Frequency

Input Signal Horizontal Frequency

Standard NTSC 480i 15.534KHz

High Resolution 480p 31.5KHz

High Resolution 720p 45KHz

High Resolution 1080i 33.75KHz


The following is a description of the signal flow for each standard listed in Table 5-2:

· 15.734KHz input: DRC circuit up-converts to 31.5KHz and MID circuit up-converters to 33.75KHz

· 31.5KHz input: MID circuit up-converts to 33.75KHz

· 33.75KHz input: XBR, HV pass through MID; HS bypass MID circuit

· 45KHz input: MID circuit down-converts to 33.75KHz


The output of the MID circuit is then applied to the CRT drive..."
yeah you keep posting this over and over

and Zaphod replied saying that the manual was not correct

the Sony CRT HDTVs display 480p, 960i and 1080i scan rates
 

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Quote:
Originally Posted by kny3twalker
yeah you keep posting this over and over

and Zaphod replied saying that the manual was not correct

the Sony CRT HDTVs display 480p, 960i and 1080i scan rates
I know I have posted this in a couple of threads. It may happen again. ;)


Zaphod hedged a little in the end: Scan Frequency Thread


lcaillo seems to be fairly certain here: Another scan frequency thread


Its not my intention to beat a dead horse, we disagree. My quote is from a Sony training document. No, I have not had the opportunity to put an o'scope on my tv. However, lcaillo's information is from bench testing.


If this tv actually scanned 480p there would be missing or double thickness lines scanned onto the screen which would create a very ugly picture. Remember, 480p has the same number of lines as 480i, they just get written at a different rate. The difference you see between 480i and 480p may actually be your HTPC de-interlacer. I see very little difference between the output of my DVD player at 480i(TV de-interlacing and scaling) and 480p(player de-interlacing and TV scaling) Until my information is proven wrong by testing, I will continue to promote it.
 

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Quote:
If this tv actually scanned 480p there would be missing or double thickness lines scanned onto the screen which would create a very ugly picture.
yes there are "blank" or missing lines with 480p scan rate

it is the only scanrate in which you can see the scan lines on the XS/XBRs

Quote:
The difference you see between 480i and 480p may actually be your HTPC de-interlacer. I see very little difference between the output of my DVD player at 480i(TV de-interlacing and scaling) and 480p(player de-interlacing and TV scaling) Until my information is proven wrong by testing, I will continue to promote it.
I am not comparing a HTPC to a DVD player

I am referring to a still image connected from my HTPC at 480p vs 1080i

Quote:
I know I have posted this in a couple of threads. It may happen again.


Zaphod hedged a little in the end: Scan Frequency Thread.
I remember but I tend to believe him

I have been members on other forums with him

and he is very knowledgable
 
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