CurtPalme.com Home Theater Forum

danielparker · Joined: 23 Sep 2007 Posts: 27

Hi,

I am successfully running my 9500LC currently with a long retrace (1920 x 817 72hz - Moome HDMI Card Version 1), and have no problems other than a lot of my images is off the left of my screen (Which I correct in software).

I decided that I would try a short retrace at the same resolution, and found that the image looked substantially better (sharper and 'punchier')

i run a 2.35:1 screen, and typically have my horizontal width set to about 95%.

Initially while cold I had had it basically set up as I wanted it.. but then once warm, I ended up with massive distortion on the screen, that can be seen here:

http://cdn.beercellar.com/misc/short.jpg (2mb)

And a short video here:

http://cdn.beercellar.com/misc/short.MOV (28mb)

I could make it stable again by reducing my horizontal width to less than 80%.

Everything went back to normal, working perfectly with my retrace set to long.

So.. my questions are:

1) Am I doing something stupid? This looked like it was going to work, and only went wrong once warm. If I let the projector cool off, it will sync again until warm.

2) What is the likely culprit here, and is it worthwhile trying to fix?

My projector has had very few mods done to it.. I have done the 16:9 vertical fix, replaced all of the fans with silent ones, and thats about it.

Daniel Parker

dvh99 · Joined: 25 Dec 2009 Posts: 2158 Location: nederland

maybe your hdm runs too hot with the silent fans.
the hdm has to work much harder with short retrace.
you could do the hdm modofication like i did which is about replacing the switching mosfets on the hdm`s heatsink.
this way the hdm remains cool while running 1080p 60 and 72hz with short retrace.

set horizontal retrace time to minimal 1,8 microseconds.

Nashou66 · Joined: 12 Jan 2007 Posts: 16171 Location: West Seneca NY

draganm · Joined: 08 Mar 2006 Posts: 8990 Location: Colorado

it might be the fans but it might not. You guys forgot I had a customer with this exact same issue and his fans were stock. Couple of other people piped in with this issue with totally stock machines, all heat related (AVS thread). I think this is why VDC re-designed the HDM with the much larger heat sink in the late model "longbow" HDM's. Scott talked about it recently.

dvh99 · Joined: 25 Dec 2009 Posts: 2158 Location: nederland

http://www2.mouser.com/ProductDetail/Cree-Inc/CMF10120D/?qs=D3QG1iK7FqhcMqyHiZ68bA%3d%3d

2 of those plus some other non expensive parts so 125 usd, running 1080p cooks the hdm.
my hdm now gets mildly warm and at 720p it even remains cold.

danielparker · Joined: 23 Sep 2007 Posts: 27

dvh99 · Joined: 25 Dec 2009 Posts: 2158 Location: nederland

https://www.curtpalme.com/forum_archived/viewtopic.php@t=9608.html

page 41.

needed,

2* cmf10120d
1* lt317 or lm317
2* 6r8 resistor 1/2 w
1* 3k9 resistor 1/4w / 1/2w
1* 260r resistor 1/4w / 1/2w
1* 100nf/50v
1* 1uf minimal 20volt electrolytic

alcohol to clean the heatsinks thermal interface material.
flux
thermal paste
wire and hot glue
2* sbyv-27/100 or 200 volt or 1n4002

Nashou66 · Joined: 12 Jan 2007 Posts: 16171 Location: West Seneca NY

Air flow rating of fans is not what you need to look at, its the static pressure . Some manufactures add this measurement in their specs, it is the amount of water deflection the fan creates. Some fans have the same amount of airflow but not enough pressure.

The way I tested fans in the PJ was to tape a piece if paper cut out to go over the air flow hole over the HDM and FCM at one end of the paper. I first measure the height of deflection with the stock fans then the new fans. If the new fans did not lift the paper to the same height it did not pass the test. I found most do not, so i left the originals in.

Athanasios