Hi,

The TV we use for informal viewing is hooked up to Comcast cable, but because the TV isn’t HD, I currently don’t subscribe to Comcast’s HD service.

The projector we use for the home theater that we recently set up can show either DVD movies or the cable TV channels. The picture from DVDs looks great—sharp and clear—but the picture when accessing the cable channels is noticeably fuzzier.

Our projector is a Toshiba TDP-T91 DLP projector, which has a picture definition of 1024 x 768 pixels. The highest quality video input is via S-Video; component input is not an option.

My question is this: Although the projector isn’t an HD unit, is there any way to use the HD capabilities of Comcast cable to improve the quality of the cable pictures so that they equal (or at least come closer to) those of a DVD movie? If there were a way, I would certainly be willing to pay any additional fees to activate that service.

P.S. It’s just a coincidence that I’m asking this question right before the Super Bowl!

Thanks,
Bill

I'm not sure what it would look like on that projector, but yes, you could get a Comcast HD box and use the s-video output to iew the HD channels.

Thanks, bfoster. If anyone reading this thread has used a similar projector with an HD signal, please let me know what kind of results you got.

Bill

as an example of a similar setup, I use S-video from a Samsung SIR-t451 ATSC digital tuner to feed over-the-air HD to an older analog Sony 55" projection TV. The shows are MUCH sharper and cleaner than the compressed mess I get from satillite.

As long as the HD set top box from your cable supplier has S-video, it should work

It should look very good, not HD, but very good otherwise.

I'm not understanding why you believe the Toshiba projector is "not an HD unit". The TDP-T91 has an HD-capable VGA input, and the specification below says it is specificly compatible with 1080i and 720p HDTV signals. If your projector works as does my NEC unit, all you need is a component video to VGA adapter cable.

http://www.projectorcentral.com/Toshiba_DPD-TDP-T91U.htm

Gary

Thanks everyone for the info. Gary, thanks for setting me straight about the HD capabilities of our projector. I bought it a couple of years ago for showing PowerPoint slides and assumed that a unit that old probably wasn't HD.

Bill

this cable "may" work, read through the technical data on the bottom of the site page. For $11 plus shipping, it may be worth the risk to try an experiment. They specifically mention it working with some projectors.

http://www.monoprice.com/products/product.asp?c_id=102&cp_id=10235&cs_id=1023503&p_id=2174&style=&seq=1&format=2#description

I've attached a portion of a diagram from the Toshiba projector user manual. I erased some parts for clarity and added my notes in red.

Does it appear from this diagram that a simple component video to VGA adapter cable will do the job, instead of needing some kind of signal converter?

See my red question mark where I find the diagram somewhat confusing. If someone could clarify what kind of attachments they are trying to show there, it would be helpful.

Thanks,
Bill

Yes, that is the VGA to Component video adapter cable I spoke of. The cable shown is VGA (aka HD15 connector) to five RCA plugs. You would use the Red/Green/Blue plugs and not connect the White/Black (those are so-called horizontal and vertical "sync" signals). Attach the cable to the projector and cable box with both powered down, and it does matter that you get the Red/Green/Blue matched correctly. (I see that your projector has two VGA inputs, both are YPbPr compatible, so select one and notice which one it is.)

The second step would be to power up the projector and enter the user menu and switch the port from VGA (aka RGB or RGBHV) to Component Video (aka YPbPr).

I'm not familiar with your cable DVR box, I'll assume the Component Video jacks are either live all the time or you can enable them with a switch, etc. Do so now, and power the box on.

You should see a sharp HD image. (Make sure you are tuned to an HD transmission.) Tweek the projector user controls for brightness, contrast, color, and to center the image on the screen. If your cable box passes 720p and 1080i in native format, you may have to perform the centering adjustments once for a 720p channel and once for 1080i channel.

Gary

I should mention that type of cable can be found at most computer stores in 6' or 8' lengths. You might need to adapt the ends from BNC connectors to RCA plugs with three adapters (UNIX monitors use BNC plugs).

Alternatively you could order the exact cable up to 50' from www.monoprice.com:

http://www.monoprice.com/products/subdepartment.asp?c_id=102&cp_id=10235&style=

...look in the section "VGA to three RCA" and you will find it in 3/6/12/25/50 foot lengths for a permanent run from cable box to projector.

Gary

Thanks everyone for the info. As the saying goes, when all else fails, read the manual. When I finally drilled down into the details of the user manual, I found that one of the projector's 15-pin inputs is dual purpose RGB and component signal. I've ordered a 25 foot RCA-component-plugs-to-15-pin cable to meet my needs. (Won't have it in time for the Super Bowl though. Sigh.)