DAB Dropouts

[gRoberts]

Hey all,

Picked up my Leon FR (2017) on Tuesday and drove home listening to my usual radio station on DAB without any issues.

Hardwired in my dashcam beneath the passenger sun visor, down the pillar and behind the glovebox.

Since doing that, I've noticed that the DAB signal is now intermittently dropping for a second and then returning.

Before I disconnect the fuse piggyback to test, has anyone else experienced this?

 

[Mr Pig]

Yes. We have a 16 and 17 plate cars and they both do it. The 17 is worse, it drops out maybe three times as often. The last car was 14 and I don't remember it dropping out very often.

We have dash cams on all the cars. I've never thought there might be a connection.

 

[Damo H]

Common issue with the power lead of dash cams interfering with DAB radio signals, although usually its when the rear is wired, not the front.

You need one of these to sort it, its what I use. If you want to go the extra mile, extra insulation wrapped around the wire.

20Pcs Clip-on Ferrite Ring Core RFI EMI Noise Suppressor Cable Clip 3mm 5mm 7mm 9mm 13mm Inner Diameter Black : Amazon.co.uk: Business, Industry & Science

20Pcs Clip-on Ferrite Ring Core RFI EMI Noise Suppressor Cable Clip 3mm 5mm 7mm 9mm 13mm Inner Diameter Black : Amazon.co.uk: Business, Industry & Science

www.amazon.co.uk

Although for me its just for the rear camera lead I need it for.

 

[Maypack]

Although for me its just for the rear camera lead I need it for.

How many did you use, where on the cable did you put them and did you put extra insulation on the cable?


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[Damo H]

How many did you use, where on the cable did you put them and did you put extra insulation on the cable?


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I only used 2, one at each end. I also haven’t used any extra insulation, that’s what @paddy6789 did.

 

[gRoberts]

Thanks everyone.

Wasn't sure if it was the difference between an external antenna that my Octavia had and the internal/glass mounted one that was the cause.

Once I've disconnected the dash cam I'll have another drive down the road it was happening on and see if I can replicate it.

 

[Maypack]

I only used 2, one at each end. I also haven’t used any extra insulation, that’s what @paddy6789 did.

One at each end, so where the cable is fed from the front camera and one at the rear?

Ive got a DAB signal drop but have only used one at the rear where the camera is.


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[Damo H]

One at each end, so where the cable is fed from the front camera and one at the rear?

Ive got a DAB signal drop but have only used one at the rear where the camera is.


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Yeah both ends for me on the rear camera wire.

Blackvue by any chance?

 

[Mr Pig]

We don't have rear dashcams but I'll try the ferrite rings anyway. Never know.

 

[Maypack]

Yeah both ends for me on the rear camera wire.

Blackvue by any chance?

Yeah DR750S.

Last question, which size did you use or are they sized for cable thickness?


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[andylong]

Yeah DR750S.

Last question, which size did you use or are they sized for cable thickness?


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For power supply wires, you can either buy the rings to slide over the insulation, or have the opening large enough to pass the cable through maybe a few times looping it through the ring. You will need longer, more tubey ones if you don't loop em. If you have an old vga cable there's always one at the monitor end and that clamps around the cable. Both supply wires will need to be done, through the same ferrite ring/core/bead if possible.

Putting them at both ends isn't needed IMO, just at the end near your device. They would normally be sized to remove the frequencies of signal you want to remove.

 

[Damo H]

Yeah DR750S.

Last question, which size did you use or are they sized for cable thickness?


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I just happen to use ones I stole from am old USB cable that were the right size for the wire...

For power supply wires, you can either buy the rings to slide over the insulation, or have the opening large enough to pass the cable through maybe a few times looping it through the ring. You will need longer, more tubey ones if you don't loop em. If you have an old vga cable there's always one at the monitor end and that clamps around the cable. Both supply wires will need to be done, through the same ferrite ring/core/bead if possible.

Putting them at both ends isn't needed IMO, just at the end near your device. They would normally be sized to remove the frequencies of signal you want to remove.

I suspect you know a lot more about this than I, I was probably just lucky that the ones I used worked.

However from memory @Maypack it was an old friend called Mikey in the MINI world that brought it to my attention. When asking about fitting the dashcam for me he asked if I had DAB and said he'd need to do something extra to stop it interfering. Then he realised it wasn't for a MINI so wasn't interested in fitting it.

Anyway this thread has reminded me that the BlackVue site had these things for sale on it as well. So I assume they'll be the right size....

Blackvue - DAB Interference Suppressor - Stops Radio Interference

Blackvue - DAB Interference Suppressor - Stops Radio Interference, fixes, dab, issues, no dab radio, problems, blackvue dab

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Blackvue - DAB Interference Suppressor - ferrite core

Blackvue - DAB Interference Suppressor - ferrite core

blackvueuk.co.uk

Pretty sure these are the same people bur the price is different. I think £8.99 is a bit expensive comapred to say Amazon, but at least you know its the right one.

 

[andylong]

It's not critical, the sizing, and anything will help. Electrically noisy power supplies ( dash cam, usb etc ) are the problem, with radio equipment being particularly sensitive due to the low level of input signal.

If you pay a tenner and they work then that's a good deal.

 

[andylong]

DAB drops out regardless of dash cams or not... My DAB drops all the time 67plate.

I would try a replacement aerial ( with better gain) or buy a signal booster. Digital radio is either working or not, unlike other radio signals which degrade until they vanish.
Also, trying to listen to stations further away will create drop outs, when there is an equivalent locally, which may have the same name.

 

[SamM2342]

Anyone any ideas why it would drop out when indicators are on? Intermittently as it flashes it goes fuzzy and during brake it perfect again?