CurtPalme.com Home Theater Forum

[as00270]

Hi

My vdc 9502 LC Ukltra has approx 135 Mhz of bandwith

Is there any way to increase this one to 140?

I try to explain why:

I am a 100% htpc user -as i am too lazy to get up and change disks - i copied , partly ripped all my movies so that now my 2 8TB disks are almost filled

My 'standard' resolution is 2560x1440@71.92 Hz - for movies

I just use analogoe input/output - shortest possible rgbhv cable (htpc is lying on the top of the projector)
htpc is equipped aith a nvidia quadro fx4800, DP - VGA output adapter (passive) kodi 15.0 qlpha, ubuntugnome 15.04
,
This gives the perfect image - for 2D movies - in 10bit color mode

For dia / slide shows or 4k i even use a 2560x2160@59.94 Hz resolution - with a 3/2 pixel aspect ratio (so a "fake"3840x2160 - but it is 2160p)
The image is so crisp sharp - i really can count each of zje 2160 lines

This resolution uses a bandwith of 133 Mhz - no problem for the VDC

# 2560x2160x59.92 @ 133.141kHz
REMOVED FOR SECURITY REASONS

(fpr people that want to try -ps. do not forget to indicate a screen size in 16/9 format( to get a 16/9 aspect ratio)

For 3D I'd like get true 1080p in 2x59.94 Hz -what doesm't work actually

As i need a minimum of 310 blanking ticks for that the full image is displayed, i would need 137 khz input bandwidth

The modeline would be:
# 1920x1080x119.88 @ 137.140kHz
Modeline "1920x1080x119.88" 305.000000 1920 2040 2072 2224 1080 1083 1087 1144 +HSync -VSync

- but this resolution isn't accepted ny my 9500LC Ultra (nor by my 8500)

By lowering to 1920x1040 it works (131 Khz bandwidth) - but that is not a native 16/9 resolution

Modeline is
# 1920x1040x119.86 @ 131.969kHz
Modeline "1920x1040x119.86" 293.500000 1920 2040 2072 2224 1040 1043 1047 1101 +HSync -VSync

For 3D, i do use 3D Vision Pro & glasses in interlaced mode (one frame left eye, one right) - kodi doea that perfectly
§D Vision (pro - or even 3D vision2(much cheaper) gives in my opinion the most impresive 3D image

All this long story for a very short question:

Which card(s) would i have to mod (or to replace) - to get 5Mhz more of input bandwidth (so approx 140 Khz) on an electrohome?
-for finaly getting true 1080p 3D?

Thanks in advance

Serge

[gjaky]

Lot of confusion here, what you want to extend is the horizontal scanrate not the bandwidth.
A Marquee Ultra should accept horizontal sync up to 150kHz, so your Ultra is not a real ultra, HDM and CLM boards are determining the maximal H scanrate. I am not sure if it is safe to run the machine at that hig scanrate, that is extremely stressing the electronics and you gain noting on screen. The tubes are nowhere near to resolve 2560x2160.

[as00270]

It seems i explained myself very badly - as i had to notice on private messages i got - and on your partly/mostly justified comment
(that's why i removed the 2160p modeline above)

I know - it's not the video bandwith -so not the VIM - as it accepts resolutions far outside the specifications
(150 MHz bandwidth (-3dB); (accommodates 3 nanosecond pixels and digital dock rates over 300 MHz),)
t
But i NEVER wanted to speak about the video bandwidth - else i would have spoken about Mhz and not about Khz

Concerning the 2160p resolution
Im my projector is a P43Lug tube

Believe me or not - you can count each line on a vertical 2160p 1pixel black / 1 pixel white test pattern (in the center of the image -unfortunately not in the extreme corners -will try to post an image these days - as proof)

Probably due to the digital clock rate far outside of the specs the colors are *softened"

With 50Hz (315 Mhz digital clock rate) - unfortunately i do see the flickering (but not all my visitors) - the image is 'stronger'

As i mentionned above in normal use i do use 2560x1440@71.92 hz
- (as well as desktop (pc use) as for 720p movies (best upscaling logically) and tv channels that emit in 720p (depending on the channel at 72 or 75 Hz)
For 1080p movies resp. 1080ii/p TV programs - 1080p@72 or 75 Hz - if i remember to change resolution

My question still persists - just it got narrowed a lot:

What parts should i mod /repair on the hdm board - to get the wanted 140 Khz bandwidth (or the normal 152Khz) -for finally getting trtue 1080p@2x60Hz for 3D?

Has anyone an idea?

Thanks in advance

[gjaky]

The max scanrate is limited by the CLM (more precisely the Deflection processor daughterboard =DPB) firmware, you have to change the appropriate chip (DPB U7 - maybe, I'm not sure) to extend the scanrate.
But you have to verify you have the right HDM (horizontal deflection module) for the 'ultra' operation too, you can do this by looking at its heatsink, as you need much better cooling for that range most importantly. Show us a picture...