Petition to stop FM being switched off

Ian Jackson wrote:
In message , The Natural Philosopher
writes
charles wrote:
In article ,
The Natural Philosopher wrote:

I mean fer chrissake I was getting RUSSIAN instead of radio 2.. on
FM. Leastways it sounded slavic. That was an FM portable..some sort
of freak atmospherics I suppose.
It was short wave broadcasts being picked up in the IF strip.
10.7MHz is on
the edge of the 25 metre band.

You may very well be right.

At the moment, propagation at the lower SW frequencies, and signals are
poor. However, for higher HF and low VHF, it's the sporadic-E season.
Only yesterday, I was hearing Italy and France on the FM radio band. You
could have been receiving Poland (but could be one of the other
Slavic/Balkan countries - and even possibly Russia). [Most have moved
their FM transmissions from 70Mhz to the 'normal' FM band.] This is one
of the reasons why NOT to re-allocate the FM band to digital.

Polish would fit. I'll say that I am on top of the highest point in
suffolk more or less, and though it aint high, the way that set had its
aerial was pointing straight over the north sea, with 40 miles of Essex
or Norfolk in between.

When I was developing FM radios, I could get a LOT of stuff off the
continent on occasion.

galaxyguy wrote:
On 26 June, 10:58, tony sayer wrote:


Perhaps I need to make my point more bluntly. I won't sign any
petition that is not written in English. Too many people these days
rely on spell check and disregard their own knowledge of our language
or are too idle to look in an English dictionary. The number of people
who will put their name to a petition written in American about UK
national British radio will be hugely reduced because it was written
in haste and without care. We should care for our language and for our
national broadcasters and ensure that in the UK we write in Engish. I
for one will not sign this scruffy document.

"we write in Engish".

Yeah, people who "rely on spell check" are idiots.

BugBear

In article , charles
scribeth thus
In article ,
The Natural Philosopher wrote:


the real solution is to go higher in frequency. Much more space, and not
already allocated. AND it doesn't hop skip and jump all over the world.

trouble is that the higher frequency the less the 'bending' round obstacles
and the less penetration through building materials.

Reflection around perhaps?..
--
Tony Sayer

In article , Roy Brown [email protected]
nthus.demon.co.uk scribeth thus
In message , Paul Martin
writing at 10:38:24 in his/her local time opines:-
In article ,
Eps wrote:

Radio 4 is in mono on DAB quite frequently in the evening whereas it's
in stereo on FM. Not sure how anyone can deny that it's better to have
stereo than mono.

I am deaf in one ear, I wish all audio broadcasts were in mono.

In theory its easy to force mono on the receiving device but not that
many actually let you.

You're not Brian Wilson, are you? :-)

It's a fallacy that someone who is deaf in one ear can't hear in stereo;
and it's a fallacy that deprived us of stereo Beach Boys recordings for
a long time :-(

While you indeed need two eyes for stereoscopic vision, the hearing
mechanism works rather differently, and can perfectly well detect the
phase and timing differences inherent in the sound from spread-out live
sources arriving via different paths - including reflected paths.

It may well be, though, that the simulation of stereo obtained by
pan-potting between two fixed point sources (loudspeakers) does not work
so well for the single ear - though turning side on to them is worth
trying.

But plain stereo over headphones certainly won't work....




A mate of mine is deaf in the one ear and has been that way since birth
but how he can tell if something is stereo or not over speakers .. dunno
quite how he does it!..
--
Tony Sayer

Roderick Stewart wrote:
In article , The Natural Philosopher
wrote:
The comparison between FM and DAB is nothing like the comparison
between gramophone recordings and compact discs. The digital bit rate
on CD is about 10 times the best rates we are now using on DAB and is
not subject to any destructive bit-rate reduction.

And that resolves to how much the compression algorithms suit teh
material being played.

I'm sure compression algorithms can be tailored for various types of
material, but the result can never be as good as something that doesn't
use any compression at all.

Lossless compression does exist.
If there is total silence, you dont need a full bandwidth to carry it..
The real point is, what is the information content?

Say you do a standard sample to say 14 bits. All the time the
music/speech is less than 14 bits deep, because its quieter, you don't
need to send the full signal.

As long as you accept delay, you can use - say - delta modulation.
That's lossless, but its 'compressed', it works because you are
guaranteed NOT to have high treble energy....which is how vinyl works
anyway. Its pre-emphasised.

The ZIP algorithm works without loss of data. For example. Because there
is redundancy in data..and repetition. I applied compression to some
HTML web forms, and got 4:1 bandwidth increase without affecting anything.

The only thing you cant compress without loss is full power full
spectrum white noise.

Anything else can be.

Whether it IS, is another matter.. I know that BBC world service, which
goes out on short wave, is MASSIVELY shaped and filtered even in the
digital online feeds. I can hear it!. There's a sharp as hell low pass
filter in there probably around 4Khz, and it gives a metallic edge to
the female voice. Of course, on a standard AM set, it may well help it
to punch through what is after all barely a 3Khz audio channel. I've
done that on AM radio as well..put in a peaking filter to get the last
scrap of bandwith out of it. helps a little.

The real argument should be about waht types of compression algorithm
are to be used. In graphics, there are many. Most code recognises most
of them. A GIF is great for black and white line art. Its crap for a
photo. Full 24 bit color goes well with JPEG, BUT beware, it copes
brilliant with fine tonal variation, but puts artefacts around small
contrasting detail.

So arguably you need different codecs for say - classical music- than
rock.

Thats the way of the future. Multiple adapting codecs. Like a standard
computer media player has. And maybe plug it into the internet to get
flash updates...






Rod.

Roderick Stewart wrote:
In article , Jn wrote:
I don't personally believe there would be enough people who want this
unless you can have some killer content/facility (just having thousands
of music/talk stations isn't that attractive). But then people do seem
willing to part with around £50/month for satellite services so I could
well be wrong, again.

Comparing my internet radio at home with other sources of the same kind of
thing, instead of having a choice of just *two* classical music stations
on FM, the same two on DAB at poorer quality, or only *one* on freeview, I
have *dozens* from all over the world, some concentrating on particular
styles of music, some of them at much better quality than any of the
alternatives. If that isn't a selling point, I don't know what is. If it's
available at reasonable cost as an option the next time I buy a car, I'll
definitely go for it. DAB doesn't offer me anything I haven't already got,
but internet radio does. Simple as that.


Abso****inglutely.

I am thinking of getting a freeview card for this computer, because by
happenstance, there's a TV outlet right by it, and listening to the
radio on it. May have to spend ,more on speaker its true..

And I am spending a fortune on bandwidth watching TV on it online..

No sure where internet multicasting is at right now, but that's another
way ..radio is for people who don't have broadband..

Rod.

"tony sayer" wrote in message
...
In article , Roy Brown [email protected]
nthus.demon.co.uk scribeth thus
A mate of mine is deaf in the one ear and has been that way since birth
but how he can tell if something is stereo or not over speakers .. dunno
quite how he does it!..

You can do it if you move your head about. I had an infection and was as
good as deaf in one ear but I could tell stereo once I wagged my head about
a bit.

Nill

"tony sayer" wrote in message
...
In article , charles
scribeth thus
In article ,
The Natural Philosopher wrote:


the real solution is to go higher in frequency. Much more space, and not
already allocated. AND it doesn't hop skip and jump all over the world.

trouble is that the higher frequency the less the 'bending' round
obstacles
and the less penetration through building materials.

Reflection around perhaps?..

Look up diffraction, very good at low frequencies where the wavelength is
long in comparison with obstacles, but not so good at high frequencies.
Having said that OFDM, the transmission standard for DAB, is very good at
reducing fading and multipath interference you'd get from GHz's
transmissions in a built up area.

"The Natural Philosopher" wrote in message
...
Roderick Stewart wrote:
In article , The Natural Philosopher
wrote:
The comparison between FM and DAB is nothing like the comparison
between gramophone recordings and compact discs. The digital bit rate
on CD is about 10 times the best rates we are now using on DAB and is
not subject to any destructive bit-rate reduction.

And that resolves to how much the compression algorithms suit teh
material being played.

I'm sure compression algorithms can be tailored for various types of
material, but the result can never be as good as something that doesn't
use any compression at all.

Lossless compression does exist.
If there is total silence, you dont need a full bandwidth to carry it..
The real point is, what is the information content?

Say you do a standard sample to say 14 bits. All the time the music/speech
is less than 14 bits deep, because its quieter, you don't need to send the
full signal.


That sounds like NICAM to me, where the data is carried in 10 bits, which
slide up and down according to volume by a further 3 bits, giving a dyanamic
range of 18 bits. BICBW

As long as you accept delay, you can use - say - delta modulation. That's
lossless, but its 'compressed', it works because you are guaranteed NOT to
have high treble energy....which is how vinyl works anyway. Its
pre-emphasised.

The ZIP algorithm works without loss of data. For example. Because there
is redundancy in data..and repetition. I applied compression to some HTML
web forms, and got 4:1 bandwidth increase without affecting anything.

The only thing you cant compress without loss is full power full spectrum
white noise.


You have to remember that all these standards were written when "cheap"
number crunching in a low cost set top box or radio wasn't feasible.

The zip compression type standard gives a variable output according to the
data being compressed. As you say, if I gave you white noise, I guess
there'd be very little compression. A similar analogy, is to watch a film
over Freeview or Sky which has a scene of falling rain, where the picture
because unpleasant and blocky.

Audio compression is generally fine as it anticipates the response of the
ear-brain which has characteristics we all suffer, the part we're going to
quibble over is the degree of compression which in DAB is squeezed to say
the least.

In article ,
Roy Brown wrote:
But plain stereo over headphones certainly won't work....

Never had done even with two good ears. ;-)

--
*Why is it that doctors call what they do "practice"?

Dave Plowman London SW
To e-mail, change noise into sound.