Digital radio switchover gets poor reception

On Tue, 25 May 2010 16:16:25 +0100, Mark Carver wrote:

Neatly combining both your points into one, I have indeed, while in
Southampton, caught the last 3 seconds of a (wanted) Radio Solent flash,
that came after an (unwanted) BBC Berks flash.

You'd have thought that the stations in a given group could come to
some arrangement over timing of their TAs. One station has 5 past
another 10 past then next quarter past(*1). Of course in areas that
have lots of local(*2) stations the frequent interuptions with
irrelevant TAs would be a right PITA.

(*1) Yeah it's not that simple with a stations located between two
main Txrs but I doubt the problem is unsolveable.

(*2) County or Regional radio would be a better description.

--
Cheers
Dave.

"Dave Liquorice" wrote in
message
ll.co.uk...
: On Tue, 25 May 2010 16:16:25 +0100, Mark Carver wrote:
:
: Neatly combining both your points into one, I have indeed,
while in
: Southampton, caught the last 3 seconds of a (wanted) Radio
Solent flash,
: that came after an (unwanted) BBC Berks flash.
:
: You'd have thought that the stations in a given group could
come to
: some arrangement over timing of their TAs. One station has 5
past
: another 10 past then next quarter past(*1).

Err! How would that help with TA flashes, by definition they are
unplanned traffic advisories, might I suggest that you are
confusing traffic *reports* with advisories - or have I got the
wrong end of the stick (quite possible as I hate TAs and thus
rarely bother activating them)...
--
Regards, Jerry.

On May 25, 7:45*am, Mark Carver wrote:
wrote:

Mark, why do I never ever hear a traffic announcement from a
commercial station, on any of my radios?

Easier to answer that by explaining how you do get traffic announcements
on BBC radio, and this will hopefully clear up some of Mike Henry's
confusion too.

When a BBC local station has a traffic bulletin, it needs to raise the
TA flag on its transmitter(s). To do this a signal is sent to the BBC's
national central RDS computer at Broadcasting House. How each individual
station does that may vary, it might be a fader start switch on the
presenter's desk, or might be a GPI from the jingle/music playout system.

Anyway, let's suppose Radio Leeds has a traffic flash. They send
notification of that to the computer, and that computer then sends over
Radio 2's [1] RDS data stream indication to Holme Moss that Leeds are
raising TA. At Holme Moss R1,2,3,4 all signal via their EON (Extended
Other Networks) stream that Leeds has raised its TA. It, in quick
succession, broadcasts all of Radio Leeds's FM frequencies, and Leeds's
PI code. At the same time it also raises TA on Radio Leeds itself.

Imagine your receiver is tuned to R4 Holme Moss (or one of its relays).
You've set TA to be active. When Leeds go to travel news, it's suddenly
told to go and try 92.4, followed by 103.9, etc. You may not be in range
of Radio Leeds at your location, in which case all you'll hear are some
brief mutes on R4 while your receiver goes and tries the Leeds
frequencies. There's a second stage, if your receiver does detect a
carrier on 92.4, it may not actually be Radio Leeds, it could be another
station, a pirate, or just RF 'noise'. So the receiver checks that the
PI code matches.

Once the travel news has finished, then Leeds should drop their TA, and
the RDS computer in London tells Holme Moss to drop the flags. If Leeds
forget to drop TA, the computer times out anyway after 3 mins or so.

In addition to the EON TA on R1-4, neighbouring BBC local stations
(Sheffield, Manchester, etc) are also signaled.

So, from the above description you can see why when tuned to any BBC
national or local station, you receive travel news from any other
receivable BBC local station. Some receivers have a 'local' / 'distant'
TA function (which Mike mentioned) that merely reduces the sensitivity
of the tuner when it's sent off to find a specified local station on the
'EON burst'.
Some receivers might have two tuners, in which case you won't hear those
mutes,

Also, note that BBC National Radio does not raise TA itself, so you
won't ever be transported from R4 to R2 for instance.

Many commercial radio stations do indeed have TA/TP, however that
signaling is normally activated by DTMF tomes embedded into their
traffic jingles. Many people assume these tones control their radios
directly, they don't. They only control the RDS coder at the Tx site,
that in turn raises or lowers TA. As there is no interaction between the
commercial stations, and certainly none between them and the BBC, you
won't hear a commercial station interrupt a BBC station with travel news
(or vice versa). All that is possible for them to do is interrupt a CD
etc, if your radio is tuned to them before you insert that CD. It's
possible that an RDS receiver with two tuners could continuously scan
the band looking for raised TAs, while tuner 1 remains on your listened
to station, that's the only situation where you could have a commercial
station interrupting a BBC one.

[1] Why Radio 2 ? *Because at the time the RDS EON/TA system was
commissioned, it was the only national network to broadcast 24/7

I've been wondering about that for donkey's years! Thank you Mark.
Another of life's little mysteries cleared up! I don't suppose you can
tell me why it is that traffic jams always happen when I'm in a
hurry?

Bill

On May 25, 3:55*pm, Mark Carver wrote:
J G Miller wrote:
And does anything similar happen with DAB local radio?

My splendid Sony DAB radio switches from DAB to FM for traffic
announcements. I wish I could buy another identical radio.

Bill

On May 25, 4:38*pm, "Dave Liquorice"
wrote:
On Tue, 25 May 2010 16:16:25 +0100, Mark Carver wrote:
Neatly combining both your points into one, I have indeed, while in
Southampton, caught the last 3 seconds of a (wanted) Radio Solent flash,
that came after an (unwanted) BBC Berks flash.

You'd have thought that the stations in a given group could come to
some arrangement over timing of their TAs.

I think they do, don't they, in a casual sort of way. I've noticed
that Sheff and Leeds never clash, nor do Derby/Leicester/Nottingham.
Anyway, I bin thinkin. (Stand back) From what Mark C says, if I set
off from Uttoxeter to drive to Rotherham, assuming I'm not going to go
up the A38 because it's rush hour and you don't need a traffic flash
to tell you that route will have jams all up the right hand side of
Derby, but assuming I'm going to go up to Ashbourne and then wend my
merry way across to the M1, then I'd be better to lock the radio onto
Holme Moss as soon as I can receive it, because that would give me the
traffic reports for the M1 north of j28 from Radio Sheff, which is
what I want. Then, if the M1 was blocked at j29 say, like is often is,
I'd get advance warning and I could go via Chesterfield. Whereas if I
let the radio hop about between Sutton C and Holme Moss like it
usually does I might miss it. Is that right Mark? Yes, you can hear R
Sheff right down there, in case anyone's wondering.

Bill

Mark Carver wrote:

Neatly combining both your points into one, I have indeed, while in
Southampton, caught the last 3 seconds of a (wanted) Radio Solent flash,
that came after an (unwanted) BBC Berks flash.

That's interesting.

I'm in the BBC Berks area and I've pretty much given up on them.

Firstly the signal is so weak the radio hops between the two
transmitters with annoying regularity (and sometimes gives up, and
switches to BBC Oxford which seems to be stronger). Don't know how you
managed to pick them up down there.

Secondly they seem to have no idea of how to turn TA on and off. The
impression I have is that they have a timer, and it comes on at set
times. On a good day you'll get the traffic news; on a bad day you get
"and perhaps the jam will have cleared up by 10. Now the football".
I've complained, and they've told me that it must be a fault in the
radio. In 4 different cars.

Thirdly they have three DJs on the breakfast show apparently with a
combined IQ of about 200. Perhaps this explains #2!

Andy

On 5/25/10 9:02 PM, wrote:
I don't suppose you can
tell me why it is that traffic jams always happen when I'm in a
hurry?

:-) That is because at those times you notice!

gr, hwh

"Andy Champ" wrote in message
. uk...
Mark Carver wrote:

Neatly combining both your points into one, I have indeed,
while in Southampton, caught the last 3 seconds of a (wanted)
Radio Solent flash, that came after an (unwanted) BBC Berks
flash.

That's interesting.

I'm in the BBC Berks area and I've pretty much given up on
them.

Firstly the signal is so weak the radio hops between the two
transmitters with annoying regularity (and sometimes gives up,
and switches to BBC Oxford which seems to be stronger). Don't
know how you managed to pick them up down there.

Secondly they seem to have no idea of how to turn TA on and
off. The impression I have is that they have a timer, and it
comes on at set times. On a good day you'll get the traffic
news; on a bad day you get "and perhaps the jam will have
cleared up by 10. Now the football". I've complained, and
they've told me that it must be a fault in the radio. In 4
different cars.

Thirdly they have three DJs on the breakfast show apparently
with a combined IQ of about 200. Perhaps this explains #2!

Andy




Your radio should not switch between Berks and Oxford if they are
different stations (rather than one being an opt-out of the
other?) Make sure your REG setting is on to stop it - by default
it usually is not.


--
Woody

harrogate three at ntlworld dot com

On Tuesday, May 25th, 2010 at 12:02:12h -0700, Wrights Aerials asked:

I don't suppose you can tell me why it is that traffic jams
always happen when I'm in a hurry?

Possibly a quantum mechanical effect dependent on the size of
the wave of probability describing your position in the traffic jam.

It may only be possible to provide a meaningful answer using string
theory, which is outside the scope of this newsgroup.

And remember, it all depends on your point of view (frame of
reference) as to whether or not you are in a hurry and whether
or not there is actually a traffic jam.

--
"String theorists don't make predictions, they make excuses."
–- Richard Feynman

Mike Henry wrote:

Sometimes there are extra slots added - stuff like "we're just hearing
about an accident at blah blah... over to Jerina Adams at the travel
centre" and they'll do an unplanned impromptu TA. But this is the
exception not the rule, and as I say they still wait until the end of the
record first! (Would like to be proved wrong again!)

The BBC LRs in the South East now all seem to use the same bloke at the end of
a crap sounding ISDN line, Barry Lewis ? So by default their TA periods are
all different.

--
Mark
Please replace invalid and invalid with gmx and net to reply.

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