CurtPalme.com Home Theater Forum

kenwrob · Joined: 21 Jul 2008 Posts: 26

I posted in this similar named thread :

https://www.curtpalme.com/forum_archived/viewtopic.php@t=42139.html

But I don't think it got noticed or responded to, so I will start a new thread and see if
any one knows what is causing this, and what the fix might involve.

Wow, I just saw this post and my G90 has been doing the same thing for a couple years now. It only does this
from a cold start and starts about a minute into warm-up, and lasts for about two minutes at which point it goes away. It is a distortion at the top third of the screen, and I have assumed it is a bad transistor somewhere and could locate it possibly using a cold spray can. But I have no idea where to look; a lot going on in the G90.
By the way the projector is ceiling mounted in my basement theater. Other than that start up glitch, it has been flawless.
Like others have mentioned, I start the PJ about fifteen minutes
before the show starts to let it warm up. The problem won't recur until the PJ is cold.
I have uploaded a video of the pj start up from cold start.
Four short iPhone videos have been combined into one and the
resolution has been downgraded, but the effect is still seen.
The color shifting is a result of the recording device as is
not seen with the eye.
Is this the issue others have seen? and if so has it been
diagnosed to a particular replaceable board.

*I have uploaded a second video with better resolution.

https://www.youtube.com/watch?v=Hq42caGZFYY&feature=youtu.be

https://www.youtube.com/watch?v=0cIP9G_oSH0&feature=youtu.be

https://youtu.be/0cIP9G_oSH0[/url]

HaydnG90 · Joined: 22 May 2006 Posts: 1356

Have you checked the CLAMP settings in the service menu? Must not be AUTO

kenwrob · Joined: 21 Jul 2008 Posts: 26

Yes, I just checked and it was in H/C position. I changed it to Auto and it didn't make
any difference. It seems to be a thermal related issue as it only occurs when the pj is
turned on from a cold start. If I turn it off for several hours and turn it back on, it
won't do it again. It only occurs from a cold start and clears up after a few minutes
of operation. Also, I am using a Moome card for input and both HDMI ports, one from
a Blu-ray and one from a Windows pc.

**Curt Palme** · Posted: Sat Feb 22, 2020 5:00 pm Post subject:

It's possible it's a bad vertical board. I should have a spare here, as would Craig Rounds.

kenwrob · Joined: 21 Jul 2008 Posts: 26

Hi Curt, is the vertical board the same as the deflection board that Craig refers to in the other thread ?

https://www.curtpalme.com/forum_archived/viewtopic.php@t=42139.html

If not, which board is it likely to be? Were you able to tell anything from the videos I posted?

**Curt Palme** · Posted: Sat Feb 22, 2020 11:16 pm Post subject:

Yup, looks like what Craig diagnosed already/

kenwrob · Joined: 21 Jul 2008 Posts: 26

OK, do you have the board I need or do I get it from Craig?

**Curt Palme** · Posted: Sun Feb 23, 2020 4:23 pm Post subject:

Get it from Craig, it will take me a while to set up a G90.
Thanks!

CIR Engineering · Posted: Sun Feb 23, 2020 4:39 pm Post subject:

It probably is your vertical deflection board and yes I do have fully rebuilt ones on hand.

However, it would be better to repair your existing board if you are able to send it to me. This is because if you keep your board your convergence and geometry will remain good after the repair. If you get a replacement board you will need to partially redo your geometry and convergence for any projector memories. Repair is a bit cheaper than a full replacement board, but both come with a full one year warranty on my work.

Best,
craigr