HDMI to DVI

[IdleWild]

Hi there,

I've got an old LCD TV, model Hitachi 26LD6200. I've just bought a new Freeview box, a Manhatten Plaza which has a HDMI output, I wanted to connect the HDMI to the TV, but I think the TV only supports DVI-I, the manual says "DVI Input (PC Only)", and I can't get my passive HDMI->DVI-D cable to get picture on the TV.

The cable works from the PC-> TV, so I guess it's the signal which is at fault.

Does anyone know if they make an active HDMI->DVI-I conversion cable? I can see an active HDMI->VGA, but nothing for DVI-I? I remember the ATI cards used to ship with a DVI->HDMI adapter. Does anyone know if it works in reverse, i.e. it can take a digital HDMI signal and convert it to DVI-I? This is the adapter I'm talking about: Removed They mention it's 'active' on that website, but looks very compact to be an active adapter.

This is the TV manual: http://www.hitachidigitalmedia.com/en-gb/brochures/102070

 

[lude1962]

Is it worth it?
High Screen Resolution of 1280 x 768 pixels
for Superb Pictures

check for 4 pins/sockets by the flat pin of the dvi socket on the telly

the freeview box may not output correct format , its likely to output 720p or 1080
the tv has a funny aspect ratio, not hd ready nor hd, nor old 4:3

 

[Rilot]

Sorry, that site sells products that OcUK sells and so is a competitor.

 

[lucid]

The signal doesn't need conversion between DVI and HDMI. They are interchangeable, so that's not the problem. The issue is the resolution and refresh rate.


Your TV expects a PC signal via the DVI-I connection. This means a progressive scan signal (P not i) with a minimum refresh rate of 60Hz (British TV uses 50Hz) and probably limited to certain common PC resolutions such as 800x600, 1024x768, 1280x1024, 1280x720. The signal from your Freeview box is none of those things. The default HD signal from the Freeview box is 1920 x 1080i @ 50Hz. None of that matches up to what the TV can accept.

To make your TV and Freeview box compatible with each other you'll need something to signal convert 1080i @ 50Hz down to a resolution that the PC input can accept, and it will also have to deinterlace and frame rate convert 50 interlaced frames to 25 progressive frames and then from that to 60 progressive frame. Those are both quite difficult things to do without some very clever processing.

The long and short of it is that budget scalers will cost as much or more than your new Freeview box and still mash up the picture, and expensive scalers will make a reasonable fist of it but cost you two or three times the price of changing the TV for a good branded 40"+ HD TV. If I was you I'd stick with RGB SCART until such time as you can afford a HD Ready TV, or look for a secondhand TV with HDMI in.

 

[IdleWild]

Just read the above, if correct might as well take the box back and get a new TV.

Not sure you're 100% correct though about conversion between hdmi and dvi. If the input is dvi-i then it would need to be converted from a digital hdmi signal to an analogue dvi-i signal. The problem with that is the extra 4 dvi-i pins are missing from my cable. And my cable works from the hdmi port of the computer which must therefore be providing a dvi-d signal.

I guess it boils down to refresh rates and resolutions. If I set the input to 1080i I get a blue screen on the dvi input but the resolution is odd and shows a 50hz refresh.

Cheapest TV 32 inch or smaller with a t2 receiver?

 

[lucid]

Just read the above, if correct might as well take the box back and get a new TV.

Yep. Unless the box has a recording feature and twin tuners then you're better off with a new telly.

Not sure you're 100% correct though about conversion between hdmi and dvi. If the input is dvi-i then it would need to be converted from a digital hdmi signal to an analogue dvi-i signal. The problem with that is the extra 4 dvi-i pins are missing from my cable. And my cable works from the hdmi port of the computer which must therefore be providing a dvi-d signal.

I guess it boils down to refresh rates and resolutions. If I set the input to 1080i I get a blue screen on the dvi input but the resolution is odd and shows a 50hz refresh.

Cheapest TV 32 inch or smaller with a t2 receiver?

Well, I am certain.

DVI-I stands for DVI Integrated. It's the version of DVI that includes connections in the plugs and sockets for both analogue and digital. That means that the other end of a passive DVI-I cable can be either a VGA connector (which is analogue only), a DVI-A connector (analogue ony via DVI, which is rare), a DVI-D connector (digital only), or another DVI-I connector (in which case the source device determines whether the output is analogue or digital), or a HDMI connector which will give just picture only since true DVI doesn't accept audio.


From the brochure you linked it says your TV has both a VGA connector and DVI connections. There's nothing that says if it's DVI-A, DVI-D or DVI-I, so I have to take your word on it that it is DVI-I. Logically though it it makes sense for it to be either DVI-I or DVI-D and not DVI-A since there's already a dedicated analogue input on the TV via the VGA connector, so duplicating with a DVI-A would be pointless. That is confirmed to since your PC to TV connection of HDMI to DVI work, so we can say for certain that the connection is at least DVI-D.

HDMI can only be digital. There is no analogue version of HDMI. There are some Chinese DVD/karaoke machines that have a broken version of HDMI where the player sends analogue via the HDMI socket and that's why Ebay is full of cables with component on one end (an analogue signal) and HDMI on the other, but these cables and those players are not standard devices. Your PC, your Freeview box and the TV all conform to the various standard that govern DVI and HDMI.

If you are connecting a source that is digital only (HDMI from the PC graphics card) to a TV that accepts a digital signal via DVI, then why on earth would there need to be a conversion to analogue? I think you're confusing DVI-I with an analogue only connection.

 

[IdleWild]

Thanks for your insight, you're correct I was mistaking DVI-I as analogue only. I thought that the PC must be providing an analogue output but then face-palmed when I realised the output is HDMI so it must be digital!

I contacted the manufacturer, and under certain output modes I am able to get a blue screen (which indicates that the resolution and frequency mode is probably supported as ordinarily I would see just a black screen). The manufacturer advises that it is likely HDCP causing the issue.

Since my TV will not support this, I am considering buying an HDCP removal device, has anyone had any luck with one of these devices? Cheaper than a new telly, especially when there's nothing wrong with this one. They seem to be ~£10 to ~£20 depending on where you source them from?