Raspberry Pi Forums

Hi,

I've got a Sony LCD TV with a RPi model B. It's 20inch (approx) and about 7/8 years old. It doesn't have an HDMI socket so I'm outputting via an RCA cable. The TV previously gave good quality picture (when connected to the TV signal).

The problem is that the output is very poor quality, very grainy. I would like to improve this. I have tried the following:

1. Swapping the RCA cable - no change.
2. Set: sdtv_mode=0 and sdtv_mode=2 - no change.
3. Set: sdtv_disable_colourburst=1 - big degradation is output.
4. Runnig tvservice –m CEA/DMT says there are no supported modes (or something similar, I'm not with my RPi at the moment).

Many thanks in advance for your help.

Rob

I've never used RCA on the Pi, but I know it fudges the analogue signal from its digital outputs (the SOC used in the Pi is a purely digital device). I wouldn't expect too much from it. If your telly has a VGA input (I have a similar aged TV without HDMI and mine does VGA), you could try an HDMI - VGA converter.

removed

CEA/DMT stuff doesn't apply when connecting by composite video connection.

Any computer connected to a TV by composite connection looks dreadful in comparison to a computer monitor connected by VGA/DVI/HDMI.

The HDMI DVI-D isn't a converter its just a cable, unlike an HDMI-VGA. I wouldn't have thought many tellies would have DVI-D. HDMI-VGA converters can be had pretty cheap these days. But a monitor with DVI-D is the better solution.

hansotten wrote:.. an inexpensive HDMI to DVI converter ...

Those are inexpensive because they don't have (or need) any electronics in them. They just change the physical connection.

Most people use the term "adaptor" for such passive devices. Active devices such as HDMI to VGA are preferably termed "converters". However such terminology is not universally followed so do not rely on it.

RobertArbon wrote:Hi,

I've got a Sony LCD TV with a RPi model B. It's 20inch (approx) and about 7/8 years old. It doesn't have an HDMI socket so I'm outputting via an RCA cable. The TV previously gave good quality picture (when connected to the TV signal).

The problem is that the output is very poor quality, very grainy. I would like to improve this. I have tried the following:

1. Swapping the RCA cable - no change.
2. Set: sdtv_mode=0 and sdtv_mode=2 - no change.
3. Set: sdtv_disable_colourburst=1 - big degradation is output.
4. Runnig tvservice –m CEA/DMT says there are no supported modes (or something similar, I'm not with my RPi at the moment).

Many thanks in advance for your help.

Rob

By default afaiaa the Composite out defaults to NTSC, and as stated HDMi settings have no effect on Conposite

See: http://elinux.org/RPiconfig video modes

RobertArbon wrote:I've got a Sony LCD TV with a RPi model B. It's 20inch (approx) and about 7/8 years old. It doesn't have an HDMI socket so I'm outputting via an RCA cable. The TV previously gave good quality picture (when connected to the TV signal).

The problem is that the output is very poor quality, very grainy. I would like to improve this. I have tried the following:

What do you expect on a 576i display?
The composite video isn't much good on my modern LG & Toshiba 42" HD TVs, it's just about usable.

You may be able to gain some clarity with the overscan options (to get square pixels), but a new TV or new DVI-D monitor would be better.

removed

It's OK, were a load of pedants on here

http://www.ebay.co.uk/itm/1-5M-HDMI-Mal ... 416a353f21

hansotten wrote:HDMI to DVI thingie

Look on ebay for HDMI to DVI ...

http://www.ebay.co.uk/itm/1M-Gold-Plate ... 1537095366 costs £3 (I've not worked out what the gold plating does for something that's 100% digital other than adding £0.89p to the price Pluggy found).

I doubt an occasional atom of gold would make much odds even if it weren't digital....