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hellmet
December 26th, 2010, 04:40 PM
Trying to save money on a new LCD, I am wondering if there is a proper way to connect my laptop to my existing CRT TV for watching movies (TV has A/V and co-ax inputs) using some device? Apart from price, another reason to stick to CRT is that in India, most (which is atleast 98%) of the TV programming is still 4:3 which doesn't make sense watching on LCD.

I've seen some simple converters on Ebay which plainly seem to change the wiring from VGA to AVI, and some box-converters too which seem to change/convert the signal for CRT compatibility. If we need a box, why are they selling the simple converters? Please help!

doorknob60
December 26th, 2010, 05:51 PM
The "simple converters" are only for graphics cards that support them. They won't work for most people. The converter boxes should though, but I'd guess they cost a lot more, but that's probably what you'd need.

mips
December 26th, 2010, 05:56 PM
Your PAL CRT TV operates on 15.625 kHz line frequency, nothing more nothing less.

The VGA port uses a frequency starting at 31.4686 kHz (twice that of NTSC-M) and any frequency above that are derived from this value by integer multiplication or division. It cannot go lower than 31.4686 kHz.

Your PAL TV will never be able to accept the higher VGA frequencies. In order to view the VGA images on a PAL (or NTSC & SECAM) TV you need a VGA Scan Converter which is a box containing electronics that converts the frequency to 15.625 kHz.

The simple cables you see only work with certain laptops that can output at the correct frequency for a TV. They are mostly a scam as they don't work in 90% of cases.

You need the electronic box, ie. Scan Converter.

What brand an model laptop do you have then we can look up the specs on the video port?

hellmet
December 26th, 2010, 06:31 PM
Thank you for the clarification mips and doorknob. I have a Dell Latitude E6400, however I'd like to use the TV with any laptop regardless of it's graphics card, so I guess Scan Converter it is, then!

Would you know if movie watching would be fine with the converter? I understand it would not match LCD in terms of picture quality, but is it worth the expense?

mips
December 26th, 2010, 06:55 PM
Would you know if movie watching would be fine with the converter? I understand it would not match LCD in terms of picture quality, but is it worth the expense?

I have never used one so I honestly have no idea wrt picture quality.

grahammechanical
December 26th, 2010, 09:17 PM
I do not know if my point of view is applicable but does your CRT television have a VGA connector? Does your laptop have a VGA connector? Then a VGA cable will work.

CRT monitors and TVs are analogue devices. The computer is a digital device. The signal has to be converted to analogue for it to work with a CRT monitor. This is what happens just the other side of the VGA connector in the computer.

The main difference between a CRT monitor and a CRT Television is the electronic circuit for tuning in a television frequency signal.

Many present day LED televisions have a VGA connector. It is only there so that these LED TVs can work with computer that only have a VGA output. They also have DVI and HDMI connectors. These two are the digital replacement for VGA. The conversion process is not needed when going from one digital device to another digital device, which i9s what a LED TV is.

The problem I think that you will have is setting a channel. Can you change the source of the signal on the TV? If it is required to tune a channel to receive video from a video playback machine then that TV might not be suitable. But then again, it might not have a VGA connector.

Regards.

hellmet
December 27th, 2010, 02:48 AM
My TV is one of the modern CRTs so it has different channels for AV, regular TV. However, I'm yet to see any CRT TV with a VGA connector in India. I guess the extra cost for the manufacturer doesn't justify in a country such as mine where people hardly own computers, forget connecting them to TVs!