DAB radio query

Jul 18, 2017
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This is the first time we have had a DAB radio facility. On using it I have noticed that it does not take much for the signal to disappear. Go down a slight dip and no signal. Go though a wooded area and signal is intermittent. I do understand that digital signal is generally line of sight, but did expect it to be so bad. Except for one big dip FM radio works 99% of the time. Bonus is hundreds of stations on DAB, but I cannot even find Radio 1, but suspect there is a "secret" to find it if you read the instruction manual. Is DAB in motor vehicles over rated?
In a home I do not foresee and issues with DAB. Totally newbie to DAB in cars so please bear with me as just looking for some input. (y) :ROFLMAO:
 
Jun 16, 2020
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I tend to leave ours on Radio 2 all the time. have little trouble with dropping out but it does occasionally. Being digital it either works or not, where FM made fade.

It still needs a decent signal. perhaps your aerial could be better. I don't know how to check that. If you have the stick aerial, they can be unscrewed and a super dupa one screwed in. but these may well be hyped up. I have the pyramid shaped one. There is also wires in the rear side windows which may have some involvement.

There are antenna options on line. But who knows if they are any good.

John
 
Jul 18, 2017
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I tend to leave ours on Radio 2 all the time. have little trouble with dropping out but it does occasionally. Being digital it either works or not, where FM made fade.

It still needs a decent signal. perhaps your aerial could be better. I don't know how to check that. If you have the stick aerial, they can be unscrewed and a super dupa one screwed in. but these may well be hyped up. I have the pyramid shaped one. There is also wires in the rear side windows which may have some involvement.

There are antenna options on line. But who knows if they are any good.

John
Don't think fit any of those to the car?
 
Jul 18, 2017
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How do you search for a particular station on DAB as there are loads? I have found Radio 2 which is our favoured station. However cannot find Radio 1, Greatest hits and some other music favourites although there are loads of music stations on DAB. Tried scanning but of course you get everything except what you want. LOL! :D
 
Nov 6, 2005
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How do you search for a particular station on DAB as there are loads? I have found Radio 2 which is our favoured station. However cannot find Radio 1, Greatest hits and some other music favourites although there are loads of music stations on DAB. Tried scanning but of course you get everything except what you want. LOL! :D
Can't speak for your Jeep but with my VW I selected a preset "button" (1-4 for Radio 1 - Radio 4), used the scan button to repeatedly search the band until the required station was present and then pressed save and moved on to the next preset.
 
Jul 18, 2017
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Can't speak for your Jeep but with my VW I selected a preset "button" (1-4 for Radio 1 - Radio 4), used the scan button to repeatedly search the band until the required station was present and then pressed save and moved on to the next preset.
Yeah that is what I was doing, but so many coming up. Took ages just to get to Radio 2 to preset it.
 
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Oct 8, 2006
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The problem with modern cars - unless DAB is fitted as standard - is that many have an aerial amp that does not cover DAB frequencies. Certainly the case if the aerial is in the back window (or the rear side in an estate).
The best thing to do is get a windscreen film aerial and connect it direct to the radio DAB aerial connection (which could be fiddley.) If that cures the problem then you know the cause, if it doesn't it may be poor local signal but unless you live in the outback that is unlikely. The BBC mux is pretty solid everywhere.
 
Mar 10, 2006
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I've had DAB in my last three cars cx-5 and Tiguan and found the DAB unusable so only use FM, I've also read that it's useless in the Sportage I'm waiting for.

Yes I know it works in some cars, perhaps it's the area I live in near Sheffield.
 
Jul 18, 2017
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Having gone through the manual, it seems that you need to scroll through the spectrum to find the station you require before allocating it to a preset. Think I will stick with FM as better coverage. Not sure if there is a Traffic Alert when using DAB? No reference to it in the manual.
 
Oct 8, 2006
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Xtrailman, it depends which stations you listen to. Sheffield has a transmitter at Crosspool for TV and radio that covers the city and most of the surrounding area quite well. DAB is also on the Chesterfield transmitter at Unstone, on Clifton alongside the M18, and on the TV relay at Stocksbridge. Add to this overlap from Holme Moss and Emley Moor. All of these carry the BBC mux, those in busy areas like Sheffield will also carry Digital 1 and SDL, and there are local radio muxes dotted about all over the place.
Having had DAB in the car for 7 years and spent much time in Chesterfield (my home town) and Sheffield (SWMBO family area) I can confirm that DAB coverage in Sheffield is as good as anywhere else and better than many.
If you want to know more look at
https://ukfree.tv/transmitters/locations/DAB
or
https://getdigitalradio.com/post-code-checker/
Note that generally DAB+ stations survive poor signal better than basic DAB.
 
Oct 8, 2006
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Having gone through the manual, it seems that you need to scroll through the spectrum to find the station you require before allocating it to a preset. Think I will stick with FM as better coverage. Not sure if there is a Traffic Alert when using DAB? No reference to it in the manual.

Traffic Alert is on FM and whilst you are listening to DAB the radio will be scanning FM stations for TA flags and switch over to whatever if it finds one. DAB also carries TA flags but is somewhat more localised.
You will need to dig into the menu system to turn TA on, and I find on our VW it helps if the last station you used on FM was a BBC national station such as R4.)
 
Nov 6, 2005
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I normally have TA switched off as I found that whilst on long journeys, TA's on local stations cutting in was of little help as I didn't know the area well enough.
Their announcers do tend to assume you know the local names of junctions, rather than the classified road number - and I get livid when they send the TA signal just after the traffic segment starts, so you miss knowing which motorway they're talking about.
 
Nov 16, 2015
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I tend to have the radio on FM radio 2, most of the time except at 12.00 when I change it to DAB, radio 4 extra, for the two hours of comedy.
 
Mar 14, 2005
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My latest VW Passat (2017) is the first one I've had with DAB (inc DAB+) and I have been very impressed with the systems ability pick up DAB broadcasts on journeys between the West Midlands and Cornwall. I detected no drop outs on the national stations I tend to use.

I think through a combination of improved DAB receivers, and the broadcasters improving transmitters, DAB is becoming a more practical proposition, However at home in the house I have poorer results with both DAB and Digital telvision,where literally cm changes to aerial position necessary to obtain continuous output.

I conclude the DAB transmissions are strongest in the open air and seem to be more easily weekend by obstructions compared to lower frequency FM signals.factor is the way the receiver responds to weaker signal strength, With FM, the signal to noise ratio reduces so the audio may have more background hiss and a stereo signal may revert to mono, but the audio is still generally continuous but just at a lower quality, where as with DAB, if an packet of data is not fully received it cannot produce its audio so it blanks it, which can lead to so quite unpleasant clicks and pops in the audio output. I do find that to be far more unpleasant than the signal fade of analogue radios.

Whether DAB is right for you, will depend on the receiver kit and the signal strength wherever you are.
 
Nov 6, 2005
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I tend to have the radio on FM radio 2, most of the time except at 12.00 when I change it to DAB, radio 4 extra, for the two hours of comedy.
I leave my radio on FM Radio 2 but with the sound turned down to zero - that way I only get the Traffic Alerts, which come in at normal volume, with peace and quiet the rest of the time.
 
Oct 8, 2006
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Prof, per the Passat, it has two aerials in the rear side windows (assuming you have an estate.) Ant1 supplies AM and FM, but both aerials are on for DAB which in effect is using diversity, that is when one aerial looses signal the other being a physical distance away my not.
In terms of data it is not serial as you seem to assume but uses a COFDM which for radio is 1705 simultaneous carriers producing a data stream. The format of the COFDM carries forward error correction so the sound does not just drop out when it looses a small quantity of data, it is capable of calculating what is missing and inserting it into the decoded stream (just like on a CD.) However when it gets to the stage that it can no longer deliver a cogent data stream it mutes it until everything is back in sync.
 
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Mar 14, 2005
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Thankyou WT.

I didn't attempt to describe the details of how DAB is encoded as it wasn't relevant other than the listening experience when insufficient complete data packets have been received.
 
Jun 16, 2020
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Prof, per the Passat, it has two aerials in the rear side windows (assuming you have an estate.) Ant1 supplies AM and FM, but both aerials are on for DAB which in effect is using diversity, that is when one aerial looses signal the other being a physical distance away my not.
In terms of data it is not serial as you seem to assume but uses a COFDM which for radio is 1705 simultaneous carriers producing a data stream. The format of the COFDM carries forward error correction so the sound does not just drop out when it looses a small quantity of data, it is capable of calculating what is missing and inserting it into the decoded stream (just like on a CD.) However when it gets to the stage that it can no longer deliver a cogent data stream it mutes it until everything is back in sync.

My estate seems to have wires in the rear windows both sides plus the pyramid bulge on the roof and there is a box of electronics under the boot floor. I can’t be sure but I think they are all part of the aerial and it is very elaborate. Pleased to say it works. less opportunity in a saloon.

John
 

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