Since installing DAB radio in the Landy and using my FTM400 on 2m or APRS TX wipes out DAB reception when keying up 
Anyone have similar and how have you fixed it?
Ferrite cores
Better earth
Better DAB aerial
Probably due to DAB being a close harmonic of 2m?. For example, DAB 218Mhz-226Mhz.
Cheers
John
Yes, it’s the well known 1.527777778x harmonic problem 
Probably going to be desense/overload. But it’s DAB and there’s A) nothing worth listening to on DAB and B) atrociously poor bitrate/sound quality so in truth, you’re most likely better off when the DAB goes quiet.
If you’re talking on 2m then surely you want to mute the background noise from the DAB radio anyway?
Can you turn down the tx power for APRS separately to the voice modes? (You can on the FT-3D)
Are the antennas near each other? Can you space them out any further?
If you’re transmitting at 50W, I think you’ll struggle to totally isolate the DAB radio from the amateur transmission - the RF could get in through the antenna, the power wiring, the case…
Nonsense. I adore BBC Radio 5 Live with crystal clear reception in my car. Audio quality is fine.
I like my DAB (Absolute Radio) once I get out of the area I am in the DAB becomes a lot better.
2m antenna is on the roof and DAB is in the Alpine window - this is in the roof on the landy.
You should get your hearing checked 
Most likely then it’s just desense. Depending on the DAB receiver there may be little to no bandpass filtering. I’m guessing your APRS squirts a packet which takes what, 0.5-1.0sec. The burst of RF flattens the DAB radio so the audio stops then it takes 2-3 secs for the DAB radio to regain sync and start decoding. Meaning a quick packet causes a good few second interruption.
I start with 1 or 2 1/4wave stubs in the DAB antenna lead. Google is your friend for designs, you want to drop the level of the 2m signal on the DAB antenna lead. See if that has any affect at all. Filter fitted as near as possible to the DAB input.
It is about 0.5-1.0 sec of data burst and then DAB returns to its normal high quality broadcast 
Thanks Andy.
I’ve seen this discussed elsewhere. I suspect that not all DAB radios (or perhaps their speakers) are equal in performance.
DAB is absolutely fine for voice and general in car use. It’s not great for audiophile listening on headphones or good speakers at home.
Provocative comment! Radio 2. Radio 5 Live. Radio Scotland.
Then we have the sound quality, which is much better than FM around here.
Only have one radio on at a time is the answer!
That’s what happened in EI. So they got rid of DAB.
Now it’s making a small comeback as DAB+ with some trial broadcasts.
RTÉ should never have demolished the 252 LW transmitter either. 
Elvis would not have agreed!
BBC Radio 4, Radio Norfolk, 5 Live and occasionally Radio 2 here. The BBC Sounds app has a really good archive (and works on Android Auto) e.g. full archive of Sherlock Holmes radio dramas etc.
Ah the sounds of my youth. Rick O’Shea, Robin Banks, Dusty Rhodes etc. on Atlantic 252.500kW during the day, then they turned the power down in the evening to 100kW or something like that.
I’ve never owned a ‘Landy’ and have spent only brief periods being driven in one but I understand that it was generally very noisy and difficult to listen to a radio inside a Land Rover Series I, II, III, and the original Defender especially while driving at speed. Many owners reported that a standard radio is virtually pointless unless the vehicle is stationary or has significant aftermarket soundproofing. That being the case, any discussion of poor bitrate or comparing the sound quality of DAB vs FM would seem a bit pointless.
My generation grew up listening to the great music of my youth on AM radio with no audio frequencies above 5kHz and often with audio compression. Before the pop pirates (Radio Caroline, Radio London, etc) started broadcasting all-day pop music on MW from ships moored 3 miles off the English coast, we would listen on a ‘trany’ [transistorised radio] to Radio Luxembourg in the evening where the long slow phase distortion due to the multipath between ground wave and skywave was a feature.
By comparison, we are spoilt nowadays.
252 LW is still around, well, not Atlantic 252 alas.
Châine 3 broadcasts on 252 LW from the Tipaza transmitter in Algeria at absolutely biblical levels of power too.
They managed to outdo themselves with the absolutely colossal power of the Kénadsa transmitter for Châine 1 on 153 kHz. If you listen carefully you can actually here the ionosphere crying as it has to hump those epic radio waves across Algeria and around the world.
Arctic 252 LW has made some test transmissions recently from a decommissioned transmitter up in Finland. Not sure if they are testing again soon before a full schedule appears.
There are concerns that it might not be worth the hassle as their broadcasts will just get swallowed up and pulverised by the sheer might of Tipaza. The fella behind Arctic 252 said it is also extremely expensive to even do the test broadcasts so it might not happen.
Châine 3 has some decent programming on a Friday and Saturday night if you like world music. Radio Romania broadcasts on LW too I think but I can never pull it in on LW, I can on SW. There’s some other LW stations around but it is slim pickings and you’d be better using a Kiwi SDR instance to try and tune in to the far flung ones.
Enjoy Radio 4 LW while you can before the BBC switch it off next year. 
It seems that BBC R4 is the last European LW broadcaster [although ghostly carriers mark the graves of some LW stations - like Radio France and Deutschlandfunk - on their former frequencies]. Listening to the wealth of LW, MW and subsequently SW broadcasts got me into amateur radio. Almost the end of an era for LW and MW.
Yes but those stations on FM sound oh so much better. DAB 64kbps MP2 audio (traditional DAB) was deemed fine for a talk radio station like BBC R4. I challenge you to listen to The Archers on DAB and FM and you’ll switch to FM, even noisy FM. Why? Because DAB Archers is in mono with no ambience or soundstage. FM Archers is stereo with people walking in from one side and exiting on the other. There’s ambience and feeling. DAB sounds stilted and dead.
If you can’t get FM then DAB becomes a Hobson’s choice. However, considering the effort and engineering the BBC went through in the 60s/70s to deliver consistently brilliant quality audio to the FM transmitters around the UK compared with how terrible DAB sounds using far too small a bandwidth. Those old engineers will be spinning in their graves at the travesty that is sound broadcasting in the UK now.
It’s all headed towards a connected future alas…which worked well recently in the Iberian blackouts.
Then what happened? All the shops sold out of ‘traditional’ radios. Lessons won’t be learned though and it’ll still point towards a connected (and controlled) broadcasting future I think.
I feel bad for the folks in parts of the world where information is suppressed, who can access more (you’d like to think) reliable broadcasts via the magnificence of SW/MW/LW. ‘Traditional’ broadcasting methods and technologies, I feel, still play an important part in the modern world that is quick to leave this stuff behind without thinking of the bigger picture first.
Andy, you have an oldie’s prospective. Different goals for a different time.
There is a huge disparity between say baby boomers and generation Z in listening to live radio. Live radio is in significant, long-term decline among younger generations. They are increasingly using on-demand digital services like music streaming, podcasts and online video platforms. Actually, that’s true for me too. Ditto live television.
If I were running a broadcasting organisation, I would seriously question how further investment in transmitter infrastructure could be justified, and even how the current infrastructure will be funded in 15-20 years’ time.
Bringing this back on topic…
Radcom Technical Topics March 1979 has designs for a 2m bandstop filter to place in a TV receiver feeder that may be just what you need. @M0VAZ
…totally agree
Geoff vk3sq