CurtPalme.com Home Theater Forum

HK-Steve · Posted: Thu Feb 02, 2012 9:14 am Post subject: Marquee Green Shaking

Hi Guy's,
got an interesting problem, green grid only is shaking and shows spikes.
Looks like a horizontal problem, but what??

See the video, half way through to the end show the best bits.

Cheers

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

have you confirmed it is a hdm problem?
exchange the red and green connectors to the tubes and see if the problem goes to red, problem could be on the conv board so if the problem doesn`t follow to the red you could swap conectors at the cva but first i would clean the contacts going to the main board and the connections from the daughterboard.

ronaldus · Joined: 25 Dec 2010 Posts: 183 Location: france

Hi Steve,

I hope it's not your super projector in your living room!

I think it's the HDM
maybe something with the ferrite width coils?
Is it there with all resolutions?
Does it happen with the internal patterns?
Did you try with a vga cable instead of the moome card?

For me it looks like some bad contact (bad GND connection that makes things oscillating)
Since it is only on the green tube it could be one of the geometry circuits like the centering ciruit.
It's also strange that the spikes are red. tha means that there's also something going on with the red circuit

This are just my first thoughts

Good luck

Ron

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

To me it looks like some kind of sync issue in the green channel if its not affecting anything else.
try a different VIM first.

Athanasios

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

Ah the dreaded horizontal scan oscillation. This is something I wanted a customer to test with the Cree FET's but ......................... Surprised

If you switch to long retrace it should go away and it should be heat related as well.
If not then it's something I've never seen before

**Curt Palme** · Posted: Thu Feb 02, 2012 9:42 pm Post subject:

Did you ever read about my DWIN shaking problem? Check the yoke connector on the green HDM output, I have had them corrode before.

Sparky015 · Posted: Thu Feb 02, 2012 11:25 pm Post subject:

If it's heat related, I would follow the thoughts of Curt. Generally heat shows cold solder joints and other flaky contacts, such as corroded connectors. Given it's only horizontal, my first thoughts would be to start at the HDM as well.

**Curt Palme** · Posted: Thu Feb 02, 2012 11:27 pm Post subject:

Yeah, ignore anything that my imposter, Nashou posts. Razz

macgyver655 · Joined: 22 Aug 2007 Posts: 8508

HK-Steve · Posted: Fri Feb 03, 2012 9:01 am Post subject:

Thanks everyone, Not my projector, but a good friends.

Shakes on internal patterns and inputs.
I did change the VIM, made no difference.
Not heat related as it happens from a cold turn on, even when it has been running for 4hrs, it happens.

I have not messed with the ferite coils, might look at bypassing them as I run 1080p only

Will check the yoke connections, and let you know.

Cheers

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

CLM/DPB?

Nashou

1031 · Joined: 22 Mar 2006 Posts: 657 Location: Finland

Hello Steve. I had similar (if i remember correct, it was time´s ago) and culprit was too short sync widht´s so if it possible try add some "pixels" to sync pulses

Tim in Phoenix · Joined: 21 Oct 2006 Posts: 4409 Location: Phoenix

Hello

Try swapping H Yoke couplers with another color, see if the problem moves. Those could tarnish over time.

.