# hdmi to vga



## cebbigh (Feb 27, 2005)

Does anyone know if it is possible to do this? I'd like to connect the hdmi output of my 942 to a vga input on a proview lcd. Would need about a 20 ft cable.


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## GeorgeLV (Jan 1, 2006)

cebbigh said:


> Does anyone know if it is possible to do this? I'd like to connect the hdmi output of my 942 to a vga input on a proview lcd. Would need about a 20 ft cable.


Not possible, VGA is an analog input. There are some component to VGA adaptors, but not all monitors support hdtv scan rates.


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## ibglowin (Sep 10, 2002)

If they make HDMI to DVI cables it would seem you could get one on those and add a DVI to VGA adapter on the end.

I think it should work.


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## DonLandis (Dec 17, 2003)

Yes, YOU'd think it would work but it doesn't. HDMI does not carry RGBHV at all. Only DVI-A carries RGBHV analog signals. Not all DVI connections are DVI-A compliant either and no HDMI is. e.g. The PVR-921 by Dish Network has a DVI that offers RGBHV if you use the proper cable. 

The point of DVI-A was to bridge the gap for those who were still using 20th century analog only CRT projectors. Today, most people are upgrading to the all digital monitors and projectors except for a few diehards who actually believe their 1980's CRT is supperior to anything out there. These were the transition years but today, most new signal generating equipment offers only composite, Y/C, and at best Y,Pr,Pb component for analog video. HDMI is fast becomming the premiere interconnect for the latest out because it offers the highest quality signal that is copy protected HDCP, and it simplifies the interconnects for the equip[ment as it also carries the highest form of audio- digital. Everything in one connection! 

If you want the highest quality analog signal on a non-digital input LCD screen then probably Y/C will be your best bet with the 942. I have an older LCD screen here and it also offers Y,Pr,Pb but nothing digital. It is a vintage 2001 LCD transition years model. Maybe your LCD also has Y,Pr,Pb component in and that would offer a tad better quality than Y/C.


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## cebbigh (Feb 27, 2005)

Thanks for the info. It looks like the only inputs on my lcd that will deliver HD are the Component inputs. Is there any easy way to split component signal 2 ways?
I'd be running approx 6 feet to my main TV and approx 20 feet to the bedroom TV. I'd try to do something with the HDMI but I've only got 1 DVI input on the main TV and it is hooked up to my OPPO DVD player.


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## dave1234 (Oct 9, 2005)

cebbigh said:


> Thanks for the info. It looks like the only inputs on my lcd that will deliver HD are the Component inputs. Is there any easy way to split component signal 2 ways?
> I'd be running approx 6 feet to my main TV and approx 20 feet to the bedroom TV. I'd try to do something with the HDMI but I've only got 1 DVI input on the main TV and it is hooked up to my OPPO DVD player.


Yes there is an easy(but not neccessarily cheap) way to split a component signal. You'll need a distribution amplifier like:
http://sewelldirect.com/hdtv-splitter-3-port.asp
or
http://www.buy.com/prod/CE_LABS_AV9...fier_1_Input_9_Output/q/loc/111/90136765.html
As a couple of examples...


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## DonLandis (Dec 17, 2003)

For the tech inclined there is a method called high impedance feed through distribution. Basically it requires some surgery on your monitor. Works like this-
You can feed several monitors using T barrel connectors, one on each of the component cables (3 of them). But normally these inputs at the monitor are terminated with a 75 ohm resistor internally. This resistor needs to be located and cut which will rasise the impedance to about 5k-10K ohms. Now you can T as many of these Hi impedance modified input monitors as you want without loading artifacts and the last monitor in the line will have the 75 ohm load terminated, unmodified. BTW- this is not a hack but the way most professional monitors are wired in a studio. These monitors come with inputs that are switched for signal pass thru or T'd or terminated by a switch, external cable terminator, or auto termination.

BTW- loading artifacts will degrade the picture too dark. High impedance artifact ( not terminated) will be seen as a too bright picture. Proper termination (75 ohms) will result in a proper brightness. If you simply T two monitors without lifting the internal resistor, your combined impedance will be 37.5 ohms, a dark picture. Also, don't think you can just increase the brightness control to compensate for low impedance because the control will not adjust the brightness linearly for all components equally. That just does not work. 

That is a cheap way but not so easy for the average person to do


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## cebbigh (Feb 27, 2005)

dave1234 said:


> Yes there is an easy(but not neccessarily cheap) way to split a component signal. You'll need a distribution amplifier like:
> http://sewelldirect.com/hdtv-splitter-3-port.asp
> or
> http://www.buy.com/prod/CE_LABS_AV9...fier_1_Input_9_Output/q/loc/111/90136765.html
> As a couple of examples...


If I can find something cheaper, guess I'll need to go this direction. Thanks for the links. Don't want to pay more for the amplifier than I paid for the TV.


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## cebbigh (Feb 27, 2005)

DonLandis said:


> For the tech inclined there is a method called high impedance feed through distribution. Basically it requires some surgery on your monitor. Works like this-
> You can feed several monitors using T barrel connectors, one on each of the component cables (3 of them). But normally these inputs at the monitor are terminated with a 75 ohm resistor internally. This resistor needs to be located and cut which will rasise the impedance to about 5k-10K ohms. Now you can T as many of these Hi impedance modified input monitors as you want without loading artifacts and the last monitor in the line will have the 75 ohm load terminated, unmodified. BTW- this is not a hack but the way most professional monitors are wired in a studio. These monitors come with inputs that are switched for signal pass thru or T'd or terminated by a switch, external cable terminator, or auto termination.
> 
> BTW- loading artifacts will degrade the picture too dark. High impedance artifact ( not terminated) will be seen as a too bright picture. Proper termination (75 ohms) will result in a proper brightness. If you simply T two monitors without lifting the internal resistor, your combined impedance will be 37.5 ohms, a dark picture. Also, don't think you can just increase the brightness control to compensate for low impedance because the control will not adjust the brightness linearly for all components equally. That just does not work.
> ...


Thanks for the info. Among the technically challenged here, so I don't think I'll try this anytime soon. Was hoping something as simple as just spliting the signal would work. But degraded image shoots the whole point of doing it in the first place.


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## cebbigh (Feb 27, 2005)

Rethinking this. Is there a simpler way to convert hdmi/dvi to component to deliver HD signal?


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## Nick (Apr 23, 2002)

No.

No more than (not then) you could convert applesauce back to an apple. 

It would be like retrofitting a modern, gasoline-powered vehicle to run on firewood and steam. 

What would be the point?


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## DonLandis (Dec 17, 2003)

Actually, Nick is off target technically with this. We do digital to component (betacam as in Y, R-Y,B-Y and back again to 1394 digital using a Convergent Design box here. It can also be done in professional DVCAM VCR's. None of this stuff is cheap. DVI to 1394 conversion is also available but not with HDCP so that is where the legal block is. However the technical solution is quite possible. The hardware is available but it is certainly not simple and not cheap! I have another box here that sold new for $800 that converted the component Y, Pr, Pb to any number of RGBHV signal specifications and there are over a dozen depending on the type of sync you need. Going from RGBHV to Component is simple and cheap, backward is not! As Nick alluded, none of these conversions is quite like taking applesauce and back to an apple but simple and cheap, no way by consumer standards.

I would look at it another way, that on most small screen displays, there will be little difference between Y/C analog and component and very little difference between component and DVI. It really is not worth worrying over. While in my HT I have a 720Px1280 projector and use mostly hdmi and DVI for all video signals, including the DVD player, my kitchen 19" widescreen HDTV and DVD player is connected via Y/C. If I connect the component cable up I can see no difference so I opted for the Y/C connection because the cable was easier to route and manage being a single tiny diameter as opposed to the component cable which is the size of 3 RG-6 cables. Obviously, if I did have HDTV signals on that system and may some day, I'll need to put the component cabl;es in place but with analog cable and DVD player, component was not worth the trouble of the fatter cable.


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## Cholly (Mar 22, 2004)

I seem to recall reading that with screen sizes below 25", it becomes almost impossible to discern the difference between 480I and any of the HD formats. I'd dbe inclined to think that Don's statement is dead on the money.

OTOH, Don -- component cable the size of 3 RG6's? Yikes!:eek2: I'd be willing to bet that an awful lot of front projectors don't have cable installations of that high a quality. Certainly, if the STB or DVD player were within 6 feet of the receiver, I wouldn't expect to see much signal degradation with even some of the low priced component cables by Philips you'd find at Wal-Mart or Target. That being said, the component cables you find shipped with a lot of equipment are pure junk.


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## DonLandis (Dec 17, 2003)

Cholly- Here's the deal.

Yes, you can use just about any coaxial cable for component. They will work. However there will be generated artifacts in some cable use that are just plain annoying. such as-

If one cable is different than the other two you could create reactance generated issues that cause frequency phase shift between the Red and blue colors. 

Some cables will generate ringing in the image due to improper impedance than what is expected at the termination point. Ringing will look like tiny outlines around hard edges.

All these issues can be observed on small monitors. They have all been reported by users trying to use a component switch box too, that is nothing more than a basic selector switch in a box---NOT GOOD!

Anyway, the large cables I referenced were really simple ones designed for component that came with several pieces of equipment. They are of large diameter and have gold RCA pin plugs at each end with a color dot for reference. 

In my edit suite, I use all RG-59U with BNC connectors for analog component signals. Some runs are 2ft and others are 30 ft. Makes no difference. Plus I use lots of Hi impedance pass through with termination on the last device.


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## Bogy (Mar 23, 2002)

3 RG6's. Almost like running Primestar, with two RG6 cable's running together. 
When we converted to DirecTV I ripped all those cables apart and saved them. Still have some around, but they are really old and I only use them in a pinch.


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## DonLandis (Dec 17, 2003)

Don't confuse RG-6 with RG-8. RG-8 is a bit over 1/2" dia while RG6 is about 5/16" dia. RG-8 is mostly used for RF transmission line like short wave radio up to 2000 watts transmitter power. In the edit suite we actually use RG-59 which is about 1/4" dia but the commercial RGB colored cables used for component connections on consumer equipment is quite bulky too. But by those standards, ever look at the Y/C cables from Monster? They are like RG-8 in diamweter.


Edited for Bogy's benefit since he is obviously reading without his glasses and is failing to see the difference between 8 and B I added a dash between the G and the 8.


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## Bogy (Mar 23, 2002)

Don, are you TRYING to confuse the issue by thowing RG8's in here? :lol:


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