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I acquired a defective LCD TV which I have already repaired. Problem is the TV only supports PAL and DVB-T and I'm in a country which uses NTSC and ISDB-T. When I tried to scan for analog channels, I was able to get channels but only the video can be displayed and no sound. This may be because the TV supports NTSC inputs through its AV in but not on the RF receiving section. It is able to display the video because it automatically detects it's format. But for sound, the difference in the sound carrier in NTSC and PAL is the reason why I get no sound. The sound carrier for NTSC is at 4.5MHz and 5.5MHz for PAL.
My question is: Can I adjust something on my hardware, probably on the tuner, to make it get the sound at 4.5MHz? or Can I replace the tuner with a compatible one that supports NTSC? or does the firmware need to be modified too?
I hope someone can help me with this. Thank you very much in advance.
 

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I acquired a defective LCD TV which I have already repaired. Problem is the TV only supports PAL and DVB-T and I'm in a country which uses NTSC and ISDB-T. When I tried to scan for analog channels, I was able to get channels but only the video can be displayed and no sound. This may be because the TV supports NTSC inputs through its AV in but not on the RF receiving section. It is able to display the video because it automatically detects it's format. But for sound, the difference in the sound carrier in NTSC and PAL is the reason why I get no sound. The sound carrier for NTSC is at 4.5MHz and 5.5MHz for PAL.
My question is: Can I adjust something on my hardware, probably on the tuner, to make it get the sound at 4.5MHz? or Can I replace the tuner with a compatible one that supports NTSC? or does the firmware need to be modified too?
I hope someone can help me with this. Thank you very much in advance.
Are there places on Earth that have not switched to digital broadcast?!
 

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Since you didn't reveal WHICH country you were in...it would have helped if you provided that info.

Many LCD TV's use Analog TV Decoder Chips that supported a wide variety of different, similar formats, so it's no surprise that many of them decode ALL of the "flavors" of BOTH PAL video and perhaps also NTSC. However, some of them used a Separate Sound Decoder Chip...with perhaps an external Sound IF Transformer/Amplifier...which would only work on ONE Sound Carrier Frequency....which would explain why video works, but sound doesn't....and NO, you can't just "redesign" the set on the fly.....

Fol. Wiki article explains the many "flavors" of PAL, with different bandwidths, scan rates, scan lines, Chroma Freqs and Sound Carrier Freqs:
http://en.wikipedia.org/wiki/PAL
You SHOULD be able to pick out which "flavor" of PAL you are dealing with....and NTSC list is found here...nearly all are NTSC-M:
http://en.wikipedia.org/wiki/NTSC
Note that PAL-M (Brazil) is VERY SIMILAR to NTSC, incl. the SAME Sound Carrier Freq (so no sound issues)...but the Chroma Frequency differences can result in Black&White pictures when viewed on a NTSC set (and vice versa)....so presumably it does NOT apply to you???

You could use a Separate OTA Tuner (e.g. old VCR) that is known to implement YOUR OTA "flavor" and connect it to VIDEO Input on the TV (YELLOW/RED/WHITE RCA Connectors).


FYI: Countries using various DIGITAL TV transmissions are listed here, incl. ISDB-T:
http://en.wikipedia.org/wiki/Digital_terrestrial_television
http://en.wikipedia.org/wiki/ISDB
From the fol. map you can see that there are numerous 3rd World countries NOT using DTV:
http://en.wikipedia.org/wiki/Digita...n#/media/File:Digital_broadcast_standards.svg
 
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