In article , Dave Plowman (News)
wrote:
In article .com,
Robert wrote:
That's a pity. On FM with poor reception one can reduce noise by
taking out the stereo decoder. On NICAM (TV) sound on channel 5 (via
analogue transmission) I find I can reduce the distortion by
switching the TV to mono (why is channel 5 so much more distorted than
the others?).

From what I have been told (by someone at the BBC) the 'mono' sound on
broadcasts is derived from the NICAM sent to the transmitters. So unless it
happens to be difference mode, any distortion on the NICAM would presumanly
also turn up on the mono sound as well.

Sounds like you have a faulty NICAM decoder. I've got a Panasonic TV
which does just this - the NICAM is distorted on peaks while the FM is
clean. But none of the several other NICAM devices on the same aerial
exhibit this effect.

I also have a Panasonic TV. If I use its 'analog' (Pair of line phonos)
outputs it gives audible distortion from loud sounds from receiving NICAM.
However sounds fed in via scart also give distortion when taken out again
via the phonos. Hence I assume it may not be the decoder as such, but poor
circuits later in the TV sound system. (The TV's speakers also produce
levels of random noise you can easily hear if you put your ear near them
with the TV volume wound down to zero. Sign of a poor power amp system as
well.)

I like the picture the TV gives, so use it as a display. The sound system
seems to me to be on a par with the kind of performance which audio systems
left behind them decades ago. Hence I simply bypass the TV system whenever
watching DTTV or DVDs.

Slainte,

Jim

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In article ,
Jim Lesurf wrote:
Sounds like you have a faulty NICAM decoder. I've got a Panasonic TV
which does just this - the NICAM is distorted on peaks while the FM is
clean. But none of the several other NICAM devices on the same aerial
exhibit this effect.

I also have a Panasonic TV. If I use its 'analog' (Pair of line phonos)
outputs it gives audible distortion from loud sounds from receiving
NICAM. However sounds fed in via scart also give distortion when taken
out again via the phonos. Hence I assume it may not be the decoder as
such, but poor circuits later in the TV sound system.

With mine the distortion goes when you switch to the FM sound (mono). It's
not a subtle difference. ;-) It's most noticeable on 'bright' speech which
is at high mod. Sounds rather like severe multi-path on FM.

(The TV's speakers
also produce levels of random noise you can easily hear if you put your
ear near them with the TV volume wound down to zero. Sign of a poor
power amp system as well.)

Not noticed that. But then it's in the kitchen so not really used for
serious stuff. Although it does feed into a sound system with a pair of LS
3/5As.

--
*Eat well, stay fit, die anyway

Dave Plowman London SW
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