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petermac
14-09-2003, 07:08 PM
I know this is nothing to do with PCs but just wondered if anyone had some answers.
I have aquired a 51in Mitsubishi Prjection TV, but it is American so is formated to run on their NTSC format. I have managed to get a picture but it is rolling. Is there a way to change a TV over to Pal or solve this issue of rolling picture or is this unit merely junk.

Thanks Pete

godfather
14-09-2003, 07:16 PM
PAL (Phase Alternate Line) is quite different to NTSC (National Television System Committee) as you have found out.

Its unlikely that you can convert the TV, if its not designed to do both.

A glimmer of hope may be in the use of a VCR as the "front end", and connect the AV Audio and Video from the VCR to the TVs input AV terminals?
Some VCRs will handle NTSC or PAL, but I strongly suspect its only off tapes, and not from the incoming antenna derived signals. I know my VCR can play NTSC tapes, and the NTSC signal then goes into the AV inputs on the TV, which also handles NTSC.

I would certainly play with a VCR as the tuner first, before giving up.

whiskeytangofoxtrot
14-09-2003, 07:20 PM
Damned yanks...

In my experience godfather is on the money - video player would be the best option.

Other alternative would be to visit a home theatre store - there should be some sort of product on the line for conversion

robsonde
14-09-2003, 07:31 PM
as far as I know if your TV is NTSC only then with a PAL signal you will get NO picture of any knid.

if you have a rolling picture then it might just need some tweeking.

godfather
14-09-2003, 08:19 PM
> as far as I know if your TV is NTSC only then with a
> PAL signal you will get NO picture of any knid.

Not so.
You will see something, but its not pretty, or useable. Rolling picture will be lack of a useable synch signal, and there wont be any colour.

If you see colour, and its just a rolling picture, then it could be an auto detect PAL/NTSC afterall.
What do you see in the way of a picture?

Pheonix
14-09-2003, 08:26 PM
Sound will be a problem as we are 5.5Mhz and states (i think) is 6Mhz. So VCR is going to be the only viable option I think.

parry
14-09-2003, 08:37 PM
Hi. I did a quick search on Google wih the keywords "pal to ntsc converter" and there are a few hits. It seems unclear (to me anyway) whether this converter goes into the TV or still needs to go through the VCR. Also looks like you can get analogue and digital converters with the difference appearing to be that analogue will not let you record the picture (ie just view on TV) while digital converters allow for both.

I suggest you talk to some TV sales shops as well as those that sell electronic equipment such as Dick Smiths etc for an idea. You will need to understand if you can convert directly to TV or if it has to go thru vcr and what are the pros/cons if you can do either (ie loss of any picture quality etc).

good luck.

tweak\'e
14-09-2003, 08:58 PM
yes pal to ntsc convertors are advaiable, however they work on the av connectios so you will need to use a video as a tuner.

wheatsack
14-09-2003, 11:08 PM
The reason your picture is rolling is that NTSC frame rate is 30fps based on the American 60Hz mains frequency while you are feeding a PAL frame rate of 25fps based on the NZ 50Hz mains frequency. If the TV has an adjustment for 'vertical' synch as some TVs have you may have sufficient range to synchronise to the PAL frame rate and then see a picture.Most modern TVs synch to the incoming frame rate which ever it is and can synch to either, older ones used the local mains frequency to assist the reciever lock to the frame rate. Since your TV doesnt naturally synch to the frame rate I suspect it wont give you colour. A standards converter in the video feed would overcome both problems (colour and synch) but they are rather expensive.Video recorders that can play NTSC tapes only add the missing colour info to the NTSC signal and rely on the TV to synch to the frame rate. NTSC has fewer 'lines'also 525 as apposed to 625 per frame for PAL hence the black section above and below the picture...your picture may look stretched vertically or be missing some heads or feet.