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Discussion Starter · #1 ·
Hello all,


The HT install rages on and I have hit a snag. I have an HD72 that I have successfully connected to my satellite box and DVD player via DVI and HDMI respectively (BTW the image is outstanding). However, I would also like to connect my tablet PC to the projector. The PC only has a VGA out. The HD72 has DVI, HDMI, component, composite and "S" video outs but I thought DVI would be the best way to connect. So I bought an inexpensive DVI to VGA adapter and installed it on the 25' DVI cable that runs to the pj. Well, there appears to be zero communication between these devices. No matter what I do; I can't get the two to see each other. I am at my wits end with this one, so if any one has any ideas on how to fix this, I would love to hear them.


Thanks!
 

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You can't just connect VGA into DVI unless the DVI port is DVI-I which supports both DVI-D and VGA signals. Only in this case will a cheap $10 pin-converting adaptor will work (VGA HD15->DVI-I).


If the port on PJ is DVI-D then it will need DVI-D like from a DVI capable video card which by the way is generally DVI-I as you can output VGA or DVI-D through this port. For example my Radeon 9800 Pro has DVI-I and I can use the included DVI-I->VGA to run into my VGA only 19" LCD monitor. I can also use the same video card without the adaptor to input into my HDMI port on my projector using DVI-D->HDMI cable.


A VGA signal can be transcode into DVI-D or HDMI but it will cost >$200 using a scaler type device or transcoder.
 

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The HD72 has a DVI-I input, so if I understand correctly, it should handle an analog VGA signal without expensive transcoding. There's even an example of this on page 12 of the owner's manual. The difference there is that they're using a VGA cable, with a passive DVI adapter at the downstream end.


Perhaps your DVI cable is actually a DVI-D (digital only)? This would explain the communication breakdown. It might be necessary to either replace it with a DVI-I or -A type, or else a VGA cable + adapter as in the manual. You'll also have to make sure that the adapter has all the proper analog pins in place as well - maybe they all do, I dunno.


I sure hope the VGA cable + adapter scheme works, because that's exactly what I'm planning to use when my HD73 arrives, and I already have the cables! Hopefully someone with more experience can tell us what's up here.


By the way, here's a link to one of several DVI FAQs out there:

http://www.dcables.net/index.asp?PageAction=Custom&ID=9


Hope this helps.


Jim the Noob
 

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Discussion Starter · #5 ·
Thanks everyone.


I will try your thoughtful suggestions and update the post. I think the issue was that I needed to configure the connection according to manufacturer's specs - with a VGA cable and the adapter on the projector end of the cable. I will try this and let you know how I make out.


BM
 

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Quote:
Originally Posted by SteveLgBch /forum/post/0


From my older Proscan DTV/HDTV box, I run a long VGA cable to a VGA-DVI adapter (the one from my Mac) and into the DVI connector on the HD72 and all works beautifully.

That's good to know, thanks for your reply.


I guess the cables are squared away - now if only had a @%$$# projector to connect them to... (sheesh)


Latest word from my vendor is "they should start shipping on Monday," but I ain't holding my breath!


Jim the Noob
 

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Quote:
Originally Posted by Bud-man /forum/post/0


No vga input on the 72, that sucks, what were they thinking?

Apparently, VGA can still be made to work. It's just not plug & play; a VGA-to-DVI adapter is needed. Presumably, any additional impedance mismatch on the part of the adapter is insignificant in terms of picture quality (I hope this is correct).
Quote:
really what good are composite or even s-video anyway....crap!

I bet the manufacturers are anxious to lose some (correction: all!) of these older formats too. It is starting to happen, actually.


I recently bought a Samsung 15" CRT TV which has only composite & component vid inputs (no S-Video). This seemed weird to me until I thought about it. With pretty much every consumer video source having moved on to component output some time ago, S-Video is becoming sort of the vestigial tail of video connections. As for composite, I'd hazard a guess that it's still simple, cheap, & adequate for enough things to keep it around (for a few more weeks, anyway).



Jim the Noob
 

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Discussion Starter · #10 ·
Now I see what the problem was for me. I was using a DVI-D cable. I need a DVI-A or DVI-I cable to be able to carry the analog signal from the PC to the projector. I have a VGA-DVI adapter but the adapter is a female and so is the DVI input on the pj (@%#$#^$^#!!!). Now I have to find a VGA-DVI adapter with a male end on the DVI side.


Oh well, at least now I know what the problem was (is).


Thanks to all for your responses.
 

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Discussion Starter · #11 ·
Just to close the loop...


I bought a long VGA cable and another (different) DVI adapter. This time, I plugged the DVI adapter into the pj and plugged the VGA cable into the adapter. I then plugged the other end of the VGA cable into the PC and it worked.


I suppose the moral to the story is ... "for best results, follow the directions" Oh yeah, the other moral to the story is "just because the connectors fit together does not mean it works"
 

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Quote:
I bought a long VGA cable and another (different) DVI adapter. This time, I plugged the DVI adapter into the pj and plugged the VGA cable into the adapter. I then plugged the other end of the VGA cable into the PC and it worked.

Glad it works for you too. I'm using this same setup with a 35' VGA cable on my brand-new HD73, and am very pleased with the picture quality.

Quote:
I suppose the moral to the story is ... "for best results, follow the directions" Oh yeah, the other moral to the story is "just because the connectors fit together does not mean it works"

Heh! Too true.



- Jim the Noob
 
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