None of Brisbanes tunnels do. And it is rather annoying.
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It really is annoying. Luckily I have a lot of presets available and I can mix DAB/FM/AM in the presets, so I keep good old 1116 AM (4BH) as a preset solely for the tunnels…
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The tunnel operators main reason for putting radio rebroadcast in tunnels is so they can broadcast information to cars in them. They do it by using a comb generator which produces a carrier on each FM and AM channel across the whole band and they receive and then modulate the local radio station audio onto the appropriate channel for the area. When they want to broadcast a message their audio just goes onto each carrier. The comb transmitters connect to the tunnels leaky feeder via a filter and combiner.
Getting DAB+ into a tunnel would be an expensive job because you would have to demodulate all the local DAB+ to audio then remodulate it onto each multiplex channel across the band. No doubt someone overseas has a solution available.
Most of Australia’s tunnel systems were designed by UGL/Comsyst at Milperra and use Powerwave gear.
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It works perfectly in Sydney. If there has been an announcement it will flick to either 2SM, WSFM or ABC Sport (depending on your MUX) with “Alarm” on my radio screen.
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And the Clem7 AM rebroadcast has 4BH spilling over into every stations audio channel.
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Most likely the AM Rx at Clem 7 (its in the Admin building at Bowen Hills) is being overloaded by 4BH due to the proximity. I guess the system is there for tunnel operator info broadcasts so audio quality is only secondary.
Given UGL are at Milperra one would imagine the Sydney tunnels would get plenty of attention from them assuming they have the maintenance contract.
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Interesting. I was caught in the Clem7 earlier in the week when that storm caused gridlock about 4pm right across the road network. I was actually stuck in crawling traffic in the tunnel for 15 mins or so and the damn emergency message could not be turned off! They were playing it every 10 seconds - not even joking. So in desperation I put my ipod on but couldn’t believe it when even with the ipod as the source the message was still coming in every 10 seconds over the top of my music. It seemed to be somehow jamming through from B105 even though I don’t even have B105 preset on FM or DAB. How the hell does that happen? It was excruciating and totally unnecessary as the traffic was basically stopped for the entire length of the 5km tunnel and the message was just warning of congestion. So annoying. The only way to stop the message was to turn the whole entertainment system off…
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Interesting, I do seem to recall FM RDS and DAB+ had an emergency alert function that unmutes and possibly even changes the frequency so that may explain your radio’s zombie behaviour - people from the RDS thread would probably know this stuff.
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Thanks, yeah it’s weird. It’s the second time it’s happened and both times it’s gone to B105
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Seems like this has been fixed.
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I heard a promo on XLFM for their Friday night “TGIF All 80s” that immediately made me think of the 2SMs DAB stations reliability
“Controlled by a Commodore 64…”
Fortunately no such issue on XLFM.
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I think we both know Bill wouldn’t want to fork out the money for a genuine Commodore 64.
I’m pretty sure those DAB stations are run off an old laptop with a bootleg version of Vista installed.
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What are other member’s models of USB DAB receiver?
My old one managed to finally rip its antenna socket off the board, and that model seems to no longer exist. I bought this, but it manages to get such awful reception with the included antenna that it struggles to get even FM reception of the nearby high power stations, let alone DAB.
So I’m already down $20 on that one - unless I potentially waste more money on finding an adapter from the little tiny socket to my roof antenna.
Anyone with a recommendation?
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I have one of the later NooElec with the SMA connector & black metal shell. So much more durable than the plastic shell dongles with the small fragile MCX RF connector.
I’ve had both the plastic shell come apart & MCT connector break on my older model.
My current NooElect dongle only does around 28MHz upwards into the the VHF & UHF band.
I see the following does LF, MW, HF & upwards.
I note that the NooElect range has expanded & prices have increased.
My later NooElect, although slightly better specs on paper, still only performs as well as the older dongle. These are 8 bit nasties, but much better made than many cheapies from China off eBay etc.
I wonder how the Airspy Mini performs?
I think many people prefer to pay a bit extra & go for the Airspy Discovery, but the problem with the Discovery is the bandwidth, 768kHz isn’t sufficiently wide enough to capture & decode the wide DAB+ channels & doesn’t do UHF.
There’s also the RTL-SDR store that’s worth looking at.
https://www.rtl-sdr.com/buy-rtl-sdr-dvb-t-dongles/
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Must have been some technical work happening overnight at Artarmon or another Sydney region DAB+ transmitter site. Had all three Sydney multiplex’s with either audio drop outs or suffering from much higher than normal BER during the wee small hours. Maybe power reduction for maintenance?
All okay this morning 
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We moved the DAB combiner at Artarmon overnight, only sites that were operational between midnight & 5am were Winmalee & Mt Badgally, there’ll be another outage tonight same time & sites, as we do some more tuning works on the DAB combiner filters.
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From the ABC help centre website
Digital Radio (DAB+) Overnight Works Sydney 12-14 April 2023
All ABC stations available on Digital Radio (DAB+) in Sydney, will be off for planned maintenance between midnight and 5am.
&
Digital Radio (DAB+) Works Brisbane 2-15 April 2023
From 2-15 April 2023, all ABC stations available on Digital Radio (DAB+) in Brisbane will be affected by planned works. During the works period the service will intermittently be off, or operating at reduced power.
Due to the nature of Digital Radio reception, listeners further from the Mt Coot-Tha transmission site may lose reception completely during low power periods.
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As far as Sydney DAB goes, no that won’t be happening, we got all the work needed done last week, so work this week isn’t needed.
As far as Brisbane DAB goes, that will be happening, they are doing antenna works at T-Site to take the notch out of the DAB antenna, so there’ll be more coverage from Mt Coot-Tha. DAB will be running under power for a while after this is done however as the antenna will need more power in for the bigger antenna (greater coverage), new transmitters are needed to do this & they won’t be installed for a few months, the current (old ones) don’t have enough power in them to make the newly required ERP, from the new antenna specifications.
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It will be interesting to see what Brisbane coverage is like when it’s completed. It was already pretty good along the Bruce and Pacific Highways.
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i wonder if it will help in the hilly areas - ive noticed for example i always lose reception on Kessells Road where it dips in front of the QEII and in Hamilton / Ascot around the hills there
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