HD set-up starts to work, then goes black

[only1chip]

I've just gotten an HD capable projector - Infocus LP530. It's hooked up to a comcast motorola 6412 STB via a DVI-D to P&D cable (Infocus calls the connector "M1" - but it's P&D).

When the STB is powered on, the Infocus syncs to the signal ("720p" is shown), it displays the message "Perfecting signal", and then displays a beautiful HDTV picture for about 5 sec. - then it goes black :( .

Anybody got any ideas what might be wrong?

FYI: the Infocus doesn't have componant inputs or I'd try that...

Thanks in advance,

Chip

[_dc_]

The DVI on the LP530 is not HDCP, so the STB is probably shutting off the signal after trying to get a handshake. If you want HD, you'll have to get an adaptor module that has component inputs.

[mjones73]

You can get a component adapter that plugs into the M1 connector from Infocus...

[only1chip]

OK, I punted on the digital connection. IF the pj doesn't do HDCP, then I 'll have to go analog...

I purchased a P&D (Infocus M1) to component video adapter from Infocus, and now I get HD but ONLY THE *&#% GREEN CHANNEL. The PJ syncs on the signal, displaying 1280x720x60Hz in a small box on the screen - but all I get is the green channel. I've tried a different reciever (same model Motorola 6412; comcast DVR HDTV combo), and different video cables, the only things left are the adapter and the projector.

After talking to Infocus tech support, I tried hooking up a laptop via the same P&D connection, but using a P&D-to-VGA adapter - and that does work; all three colors at 1024 x 768 (not HD or HD resolution, but darn close on the res.).

I even got a VGA-to-Component cable and used it in conjuction with that working VGA cable to go from Componant-to-VGA-to-P&D - and it's back to syncing on HD (1280x720x60Hz) but it's still green channel only! ARG! This test was basically to eliminate the adapter mentioned in the first paragraph.

I can only deduce that either the PJ is malfunctioning, or there is some wierd incompatability between the Moto STB and the PJ...

Anybody got a clue???

Thanks,

Chip

[only1chip]

Answering my own question...

I have it working now.

I found out that the "color space" for the comcast/motorola STB (HDTV) is different from what my pj can handle. Even though my PJ is HDTV capable, it is somewhat old, apparently older than the final HDTV spec.

There are several adapters available,the ones I found range from $45 to $400. I chose the following model. It's componant-in, VGA-out. I use the VGA to M1 cable that came with the pj with this adapter.

This adapter is more than a funny cable with different ends, I tried all of those.

http://ps2modchip.com/VGAA.php

Hoped this might help someone else...

Chip

[only1chip]

Another option, and more details about the color space issue:

This "adapter" is a lot more money...

http://www.laaudiofile.com/cc3cv3.html

Chip

[mjones73]

That's a transcoder actually..