RGBHV problem

[captain slagle]

OK, I'm new to this. I just got an epson powerlite 7350 and digital cable. The projector has the RGBHV BNC inputs and I just got rca to bnc adapters and plugged the RGB plugs into the RGB spots and regular channels work fine. But when I try to watch HDTV channels there is no picture. The projector has a YCbCr function that I have it set on. Is this the same as YPbPr? If not, is there a cheap way to convert DVI-D to this format? Or are there any other non-conventional approaches to this? I am looking for the cheapest possible solution here. Thanks!

 

[BMXTRIX]

What is the involvement with DVI-D? Are you trying to connect the HD box via the component RCA outputs, or via the DVI-D output? If the later, then you can't do that. DVI-D is digital (zeroes and ones) while RCA/BNC connections are analog.

 

[captain slagle]

OK, so DVI-D is out. But what about the component? Right now I have my CPU hooked up via a huge SVGA cable but just the standard single RCA video cable. Basically, I am looking for the cheapest, easiest way to get HD through my projector. I am open to any ideas. If you tell me to build a wooden satelite dish and put it on the roof of my car with an extension cord I will do it (as long as I get an HD signal).

 

[BMXTRIX]

Your cable box should have component video output and that projector should have component video input.

For HDTV you must use component video or DVI. The projector doesn't have DVI, so you must use the component video connection. Out of the cable box should be red, green, and blue video connections (component) and those connect to the input of the projector.

Do not confuse owning a digital cable box with owning a HDTV digital cable box. They are different.

 

[RLA]

Hello
It sounds like you are trying to use HTPC for you projector? This has many advantages 1:1 pixel mapping is one Here is a simple cost effective solution for your HDTV needs using your HTPC.
http://www.digitalconnection.com/Products/Video/mdp130.asp

 

[captain slagle]

Well the problem is that my cable box has the component YPrPb output but my projector has the BNC RGBHV. It also has a YCrCb setting, with this I get normal channels, but when I turn to an HD channel the projector cannot recognize the input and the screen goes blank. What is the difference between YPrPb and YCrCb? How do I get these things to get along? The projector also has VGA inputs, are they digital? The cable box has DVI-D component YPbPr. I am just lost as to which is the best/easiest/cheapest.

 

[satish536]

YPrPb YCrCb

Basically ill let u know as far as i know, im not sure so anyone can correct me if im wrong........

YPrPb- This means the the signal flowing through is progressive scan
YCrCb- This means the the signal flowing through is Interlaced

Thats the difference as far as i know, there are way more knowledgable people on this forum who'll give u much more info on this.

 

[MDS]

YPrPb- This means the the signal flowing through is progressive scan. YCrCb- This means the the signal flowing through is Interlaced.

Yes and No.

YPrPb is analog component video. YCrCb is digital component video.

Use DVD as an example:
The video is interlaced and stored as YCrCb (compressed with MPEG-2). If the player is in progressive mode, it will deinterlace the signal and send it out the component video outputs. The format it sends out is YPrPb (480p) and the display device must accept YPrPb for it to work.

DVI is purely digital, so it will always be YCrCb.

 

[captain slagle]

so is there a way to convert say DVI-D to YCbCr? Or to RGBHV?

 

[AVRat]

BMXTRIX mentioned this but I'll ask again, did you get HD service along with the digital cable service??

 

[captain slagle]

yes, i did get HD service with the cable. and it is an HDTV cable box. and the projector specs say it is capable of HD. The only problem is going from the cable box to the projector.

I found converters from component YPrPb rca plugs to vga connecter, would this be HD? I also found all kinds of breakout adapters, but I really dont know what im looking for. Just cheap decent HD quality, thats what im looking for. Sorry if i am giving you guys too much info, but it just seems that there are a ton of different ways to go about this issue. i appreciate your patience, Im a newbie at this stuff.

 

[BMXTRIX]

Alright - here is my shot in the dark answer without seeing an owners manual.

Your projector is ancient.

That is, it is like a 6 year old computer - not a horrible thing to have a 6 year old computer, but it isn't a P4 by a long shot.

My guess is that the projector only accepts HDTV (1080i, 720p) in the RGBHV color space and your cable box only outputs HDTV in the component video color space.

You need to transcode from component video to RGBHV.

Something like this:
http://cgi.ebay.com/VDIGI-VD-Z3-Component-VGA-transcoder-XBOX-PS2-DVD-VD-Z3_W0QQitemZ8219946771QQcategoryZ41015QQssPageNameZWD10VQQrdZ1QQcmdZViewItem

... should work as it says it does convert from 720p and 1080i component to RGBHV color space.

Now just for fun I went and got the user's manual:
http://files.support.epson.com/pdf/pl5350/pl5350u1.pdf

er.... it looks like on page 51 of the manual that the projector can auto detect the type of video signal.

On page 97 it says that in the 'advanced' menu there is a setting for the signal type and you can choose from about 9 different formats including 'auto'. Strangely, 1080i and 720p are not listed as options... weird.

Not much help beyond this though from me. Good luck!

 

[Votrax]

Page 158 says it supports 480i, 480p, 720p, and 1080i. I suspect the issue is with the setup of the cable box.

 

[Phantomguy]

Inputting to GRBHV

Page 158 says it supports 480i, 480p, 720p, and 1080i. I suspect the issue is with the setup of the cable box.

Hi. Not sure if I can be of any help here but I have just had 3-4 weeks of similar problem with BenQ PE7800HD2+ projector. Until I get new Yammie 2600 AC revr I am feeding the projector from Teac HD tuner (free to air) and SD cable box (Pace TSC460NF) - that is because I am in Australia at present and that's all that is offered for cable. OK .. the issues ... BenQ finally admit that thru DVI the unit wont upscale to output 1080i just native 720p (but not broadcast here). They have tested 1080i out of Tuner through DB15 (Dsub) and in through 5BNCs (GRBHV) and then projector DOES output 1080i. (Theirs NOT mine .. mine a lemon). IT WILL NOT PROCESS as high as 1080i through DVI so falls back to 540p; NOR thru YUV (YPbPr 3 RCAs) so falls back to 540i BUT it will process SD at 576p or 576i depending on source. So I expect the same to be true for 480p and 480i. Now for cable Box I outputting ONLY 576i on ONLY SCART (horrible!!) the picture symmetry is wacko and with NO AUTO on this projector all other manually selected formats are also wacko. CONFUSED? SO WAS I.

OK.... the upshot of all this is that a lot of these projectors - especially with 5BNCs for R, G, B, H and V will ONLY output HD if input is by DVI or GRBHV and in the case of the DVI ONLY the native format (720p) and if any of deinterlacing/reverse 3:2 pulldown/rescaling/transcoding needs to be done you MUST input THE RAW SIGNALS thru the 5BNCs which include separate H and V sync.

The problem is YPbPr is composite and combined H+V sync on Y, with chrominace shift on the Pb and Pr and is a much lower bandwith than RGB in whatever form of RGB. So I suspect the KEY here is to get your signal into GRBHV(5BNC) or GRBH (4BNC) if your projector will accept combined sync on V(vertical) alone (specs??). If I read you right your cable box only puts out YUV?? Right? Well that could be not good enough for the projector to display HD and in correct symmetry. I suspect the user interface (software) in your cable box allows you to output RGB or YUV through the 3RCAs (??) on the back of it or has a D-SUB15 on the back.

If a DSub 15 then you can male a a cable from Dsub15 female to 5 or 4 BNC. see http://www.tkk.fi/Misc/Electronics/faq/vga2rgb/scart.html If only 3RCA then you will need to check with box maker if the RGB is RGsB (with combined H and V syncs on Green pin) and then IF your projector will accept combined sync on V (as stated earlier in my post) you can feed the V from the Green (susepct will will need to filter out the Green signal with suitable componentry) BUT if like me your projector MUST have separate H and V syncs then the same link in the last paragraph is an IC setup that might help.
Good luck. Phantomguy.