emeregency radio broadcast interruption

GabbaGabbaHey

DUTR wrote: »

It's not the TA, it's the TMC which overides and listened to station, where as TA is only on the specific listened to station or EON shared station.

Except if you have a dual diversity tuner (such as the Becker system fitted to many BMWs and Porsches) where you can listen to one FM station (which does not have a TP flag set) and still monitor TA on another.

DUTR

GabbaGabbaHey wrote: »

Except if you have a dual diversity tuner (such as the Becker system fitted to many BMWs and Porsches) where you can listen to one FM station (which does not have a TP flag set) and still monitor TA on another.

Dual diversity tuners are to reduce interferance from multipath radio reflections.

DUTR

Rodders53 wrote: »

TMC is a data channel carried on Classic FM I think which is used to warn of traffic jams via sat nav units typically... not what is being described by the OP which involved audio via the car radio.

IIRC some tunnels in the UK have a 'leaky feeder' cable installed to carry the broadcast services (otherwise inside the tunnel you lose signal completely) and these have the ability for the tunnel operators to 'cut in' and override ALL services... which seems the OP heard a test of the facility (no point having it if it isn't tested).

http://www.landmobile.co.uk/news/londons-road-tunnels-radio-systems-what-lies-beneath

Rotherhithe and Limehouse seem to have this ... maybe Blackwall has been upgraded since the article?

There are 32 flags that can be set, ALARM being one of two them, I remember my 2nd Pioneer RDS unit, mentioning this in the booklet, never seen it activated though.

GabbaGabbaHey

DUTR wrote: »

Dual diversity tuners are to reduce interferance from multipath radio reflections.

Sorry, I meant "dual tuner" - the "diversity" just crept in there.

The point is that you can listen to one FM station and monitor TA on another.

DUTR

GabbaGabbaHey wrote: »

Sorry, I meant "dual tuner" - the "diversity" just crept in there.

The point is that you can listen to one FM station and monitor TA on another.

No need to apologise, the current VW and MK5 have DT recievers then , as I could listen to AM and still get traffic announcments.
I remember reading up on the RDS standard in the 90s, alarm was definately a feature.