DAB Signal stronger when car key is in position 1...?!

TeddyRuxpin

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Hi,

I added the OEM DAB module and wiring loom to my car a few years ago - the only thing that isn't OEM is the aerial, which is the stick on type on the front windscreen. DAB functionality enabled in the engineering menu.

Signal has never been amazing with frequent loss of signal.

Anyway, I've noticed that if the car is running and there's no signal, if I switch the key to 'off' (or 'position 1'), I'll often get signal.

What's that all about? Is it normal? Fixable? Is something interfering with the signal when the car is on?

As an aside - The aerial was a cheapish £15 job from amazing. The receiver actually has two aerial spots, but I just used one, following the meagre instructions found online. Not so sure what the other aerial port is for... double the power?

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m80

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Do you have USB type kit that powers up in pos 2?
This stuff is known to produce RF interference that upsets FM, I don't know if that's the same for DAB.
 

geoffus

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I have a dash cam fitted in the windscreen, my DAB is awful when the dash cam comes on, I’ve tried everything to cure it to no avail, it must produce so much noisy interference.
 
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m80

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I have a dash cam fitted in the windscreen, my DAB is awful when the dash cam comes on, I’ve tried everything to cure it to no avail, it must produce so much noisy interference.
Is your antenna integral to the front screen? Some are rear screen and I would've thought a dash cam to only have effect if it's by the antenna.
 

geoffus

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Is your antenna integral to the front screen? Some are rear screen and I would've thought a dash cam to only have effect if it's by the antenna.
Yes I believe it is integrated inside the front screen.
 
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m80

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Yes I believe it is integrated inside the front screen.
I have a similar issue on the 639, but I have 2x mobile charger cradles and the dash cam. I'm thinking to mount a new amplified antenna into the rear roof to distance the antenna from the USB kit.

Op, you could try disconnecting such kit, if you have it. Some makes worse than others, but that can be expensive trial and error.
 

geoffus

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I have a similar issue on the 639, but I have 2x mobile charger cradles and the dash cam. I'm thinking to mount a new amplified antenna into the rear roof to distance the antenna from the USB kit.

Op, you could try disconnecting such kit, if you have it. Some makes worse than others, but that can be expensive trial and error.
I did disconnect my dashcam but the DAB signal still wasn't great, is it possible to have good DAB reception from a moving vehicle ?
 

m80

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I did disconnect my dashcam but the DAB signal still wasn't great, is it possible to have good DAB reception from a moving vehicle ?
I can't give an answer a I've no experience of DAB. Maybe others know better.
 

Continental

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Just saw these comments and imagine you’ve tried it but thought I’d mention it anyway just in case … magnet around the dashcam power wire… they usually come in a clip on form.

Also if the dashcam power cable did not come with a magnet it could be a case of that cable not being very well insulated - might be worth swapping it out (the power cable at least) entirely for a better quality one.
 

Larkone

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Had this issue when I fitted DAB and dashcam and ran the power wires up the same pillar. The answer was to re-route the dashcam power up the other pillar, well away from the DAB unit and aerial. DAB signals are generally flaky on the move, especially if the road is heavily tree lined. How they can think it will replace FM.
 

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