Digital radio switchover gets poor reception

On Mon, 24 May 2010 20:14:05 +0100 (BST), "Dave Liquorice"
wrote:

On Mon, 24 May 2010 19:57:28 +0100, Petert wrote:

I think it's TP (Traffic Programme) which is perminantly illuminated

That just tells you that the station you are tuned to carries tarrif
information if you want to hear other stations Traffic Announcements
you need to have the TA flag on as well.


Thanks dave - you learn something new every day!!
--
Cheers

Peter

(Reply to address is a spam trap - pse reply to the group)

On Mon, 24 May 2010 20:30:47 +0100, Mark Carver
wrote:

Petert wrote:
On Mon, 24 May 2010 19:10:26 +0200, hwh
wrote:

On 5/24/10 5:26 PM, Petert wrote:
I used to get traffic reports for North Devon while driving along the
Gower Peninsula, in my last car (406 with FM radio), but get no
traffic reports at all from the FM radio in my Merc :-(
Very likely there is a switch to enable it.

gr, hwh

I think it's TP (Traffic Programme) which is perminantly illuminated

That means the station you're tuned to has a travel news facility, however to
activate your radio to give travel news interruptions you normally need to
active a TA function. The 406 radio has a TA button, it might be rather more
cryptic in your Merc !

I'm sure you're correct - I shall take a look
--
Cheers

Peter

(Reply to address is a spam trap - pse reply to the group)

Mike Henry wrote:
In , Petert
wrote:

On Mon, 24 May 2010 20:14:05 +0100 (BST), "Dave Liquorice"
wrote:

On Mon, 24 May 2010 19:57:28 +0100, Petert wrote:

I think it's TP (Traffic Programme) which is perminantly illuminated
That just tells you that the station you are tuned to carries tarrif
information if you want to hear other stations Traffic Announcements
you need to have the TA flag on as well.

Thanks dave - you learn something new every day!!

Also whilst we're on the subject you may find this helpful. I remember
reading on one of these groups that they "ran out of space" (paraphrased)
in the lookup tables for RDS Traffic Announcements stations. They had to
split the UK stations into two separate lists, massively reducing the
potential of the RDS TA function.

We have all the BBC stations (lots of them including the local ones) in
one table, and all the commercial stations in a different table, IIRC.

Stop there Mike, you've got the wrong end of the stick I think. What happened
is the BBC changed the PI codes of some of its local stations away from
generic linking, because in some overlap areas car radios would 'hunt' between
stations, nothing to do with TA/TP. There is no link or otherwise of any
'tables' other than the 'non-clashing' PI codes between BBC and commercial
stations. The only connection is that BBC stations carry EON static data
referring to Classic FM AF codes and vice-versa.

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

www.paras.org.uk

On May 24, 10:23*pm, Mark Carver wrote:
Mike Henry wrote:
In , Petert
wrote:

On Mon, 24 May 2010 20:14:05 +0100 (BST), "Dave Liquorice"
wrote:

On Mon, 24 May 2010 19:57:28 +0100, Petert wrote:

I think it's TP (Traffic Programme) which is perminantly illuminated
That just tells you that the station you are tuned to carries tarrif
information if you want to hear other stations Traffic Announcements
you need to have the TA flag on as well.

Thanks dave - you learn something new every day!!

Also whilst we're on the subject you may find this helpful. I remember
reading on one of these groups that they "ran out of space" (paraphrased)
in the lookup tables for RDS Traffic Announcements stations. They had to
split the UK stations into two separate lists, massively reducing the
potential of the RDS TA function.

We have all the BBC stations (lots of them including the local ones) in
one table, and all the commercial stations in a different table, IIRC.

Stop there Mike, you've got the wrong end of the stick I think. What happened
is the BBC changed the PI codes of some of its local stations away from
generic linking, because in some overlap areas car radios would 'hunt' between
stations, nothing to do with TA/TP. There is no link or otherwise of any
'tables' other than the 'non-clashing' PI codes between BBC and commercial
stations. The only connection is that BBC stations carry EON static data
referring to Classic FM AF codes and vice-versa.

--
Mark

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

Bill

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

In article
..com, scribeth thus
On May 24, 10:23*pm, Mark Carver wrote:
Mike Henry wrote:
In , Petert
wrote:

On Mon, 24 May 2010 20:14:05 +0100 (BST), "Dave Liquorice"
wrote:

On Mon, 24 May 2010 19:57:28 +0100, Petert wrote:

I think it's TP (Traffic Programme) which is perminantly illuminated
That just tells you that the station you are tuned to carries tarrif
information if you want to hear other stations Traffic Announcements
you need to have the TA flag on as well.

Thanks dave - you learn something new every day!!

Also whilst we're on the subject you may find this helpful. I remember
reading on one of these groups that they "ran out of space" (paraphrased)
in the lookup tables for RDS Traffic Announcements stations. They had to
split the UK stations into two separate lists, massively reducing the
potential of the RDS TA function.

We have all the BBC stations (lots of them including the local ones) in
one table, and all the commercial stations in a different table, IIRC.

Stop there Mike, you've got the wrong end of the stick I think. What happened
is the BBC changed the PI codes of some of its local stations away from
generic linking, because in some overlap areas car radios would 'hunt' between
stations, nothing to do with TA/TP. There is no link or otherwise of any
'tables' other than the 'non-clashing' PI codes between BBC and commercial
stations. The only connection is that BBC stations carry EON static data
referring to Classic FM AF codes and vice-versa.

--
Mark

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

Bill

Dunno perhaps they either don't transmit them.. Or don't know how to;!..

There was a joke about "raising the travel flag" at one local station a
while ago quite amusing the presenters just believed that they had to
lift it up in the studios and wave it at the microphone...
--
Tony Sayer

On Tuesday, May 25th, 2010 at 07:45:17h +0100, Mark Carver explained:

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.

How does the system and Holme Moss cope if BBC Radio Leeds,
BBC Radio Manchester, and BBC Radio Sheffield all have a traffic
flash at the same time?

And presumably if BBC Radio Manchester raises a traffic announcement,
then a signal is also sent to Winter Hill as well as Holme Moss?

And does anything similar happen with DAB local radio?

J G Miller wrote:
On Tuesday, May 25th, 2010 at 07:45:17h +0100, Mark Carver explained:

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.

How does the system and Holme Moss cope if BBC Radio Leeds,
BBC Radio Manchester, and BBC Radio Sheffield all have a traffic
flash at the same time?

I assume the system will send the EON bursts in quick succession, based
on the order the stations are stored in the computer's tables ?

If a second station has a travel flash while the first one is still in
progress, some receivers will then switch to that second one, on
completion of the first. Other not so clever radios, just return to the
original station.


And presumably if BBC Radio Manchester raises a traffic announcement,
then a signal is also sent to Winter Hill as well as Holme Moss?

Yes, it's sent to any national transmitters that are likely to be in
range for that local station.

For instance Radio Berkshire gets mapped to Wrotham, CP, Rowridge, and
Oxford (plus all their relays of course)

And does anything similar happen with DAB local radio?

Dunno.

On Tue, 25 May 2010 15:55:20 +0100, Mark Carver wrote:

I assume the system will send the EON bursts in quick succession, based
on the order the stations are stored in the computer's tables ?

If a second station has a travel flash while the first one is still in
progress, some receivers will then switch to that second one, on
completion of the first.

By which time the second TA could have finished?

So it is possible that somebody needing a TA for Sheffield misses
the TA because his radio has been trying to tune in BBC Radio Manchester,
and for other permutations of Leeds, Sheffield and Manchester?

For instance Radio Berkshire gets mapped to Wrotham, CP, Rowridge, and
Oxford (plus all their relays of course)

Listeners in the Isle of Wight must regard it as somewhat irrelevant
though

J G Miller wrote:
On Tue, 25 May 2010 15:55:20 +0100, Mark Carver wrote:

I assume the system will send the EON bursts in quick succession, based
on the order the stations are stored in the computer's tables ?

If a second station has a travel flash while the first one is still in
progress, some receivers will then switch to that second one, on
completion of the first.

By which time the second TA could have finished?

So it is possible that somebody needing a TA for Sheffield misses
the TA because his radio has been trying to tune in BBC Radio Manchester,
and for other permutations of Leeds, Sheffield and Manchester?

For instance Radio Berkshire gets mapped to Wrotham, CP, Rowridge, and
Oxford (plus all their relays of course)

Listeners in the Isle of Wight must regard it as somewhat irrelevant
though

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.