Nextbase Dash cam DAB Radio Interference

LordByronUK · February 13, 2021

So we've just figured out why our DAB Radio signal has been terrible last several months... It's the bloody nextbase 522 dashcam causing interface. Turn the cam off and it's perfect again.

I got them to hardwire it into the fuse box so no cable is visible apart from the small section coming out of camera into the trim. I will try to place a ferrite core around that bit, but failing that, any other suggestions guys? Anyone else has this problems?

Oh and guess what once again, I asked the dealership what could be causing it and they didn't have a clue as usual...

Thanks

Herbie · February 13, 2021

I don't think there is anything else other than ferrite cores/beads that would work.

There should be plenty slack in the roof lining so do that end first and see if it helps. The other end will only be a piggyback fuse so again, should be easy enough to do.

ColinBarber · February 13, 2021

A common problem with the 522 - seems a very poorly designed device.

If you have the rear camera then you may want to reroute the cabling on the other side of the vehicle so it is far away from the DAB antenna and signal cable.

LordByronUK · February 13, 2021

Just got the front camera, so I'm surprised it's as bad as it is. Thanks guys, will give the ferrites a go!

ColinBarber · February 13, 2021

32 minutes ago, LordByronUK said:

Just got the front camera, so I'm surprised it's as bad as it is. Thanks guys, will give the ferrites a go!

What vehicle do you have - your profile shows an IS300h but you have posted in the NX forum?

The NX has its DAB antenna at the top/middle middle of the windscreen, I guess right where your cam is.

LordByronUK · February 13, 2021

1 hour ago, ColinBarber said:

What vehicle do you have - your profile shows an IS300h but you have posted in the NX forum?

The NX has its DAB antenna at the top/middle middle of the windscreen, I guess right where your cam is.

Yes, I have an IS300h and partner an NX300h. Yeah adding a ferrite core on the section of cable coming out the dash cam should do the trick, off to Halfords tomorrow. Cheers!

LordByronUK · February 14, 2021

21 hours ago, ColinBarber said:

What vehicle do you have - your profile shows an IS300h but you have posted in the NX forum?

The NX has its DAB antenna at the top/middle middle of the windscreen, I guess right where your cam is.

So I tried my ferrite core on the cable where it comes out of the dash cam right next to the DAB antenna, but it didn't work. Any other suggestions?

Herbie · February 14, 2021

34 minutes ago, LordByronUK said:

So I tried my ferrite core on the cable where it comes out of the dash cam right next to the DAB antenna, but it didn't work. Any other suggestions?

So you only got one? I'd have got one for each end.

How many turns did you give it?

ColinBarber · February 14, 2021

28 minutes ago, LordByronUK said:

So I tried my ferrite core on the cable where it comes out of the dash cam right next to the DAB antenna, but it didn't work. Any other suggestions?

Did you managed to wrap the lead around the core multiple times? The more the better.

Get some aluminium foil and completely cover the unit in it. If the radio is then ok it suggests that the device is emitting interference that is only going to be resolved by relocating it, or using a different dash cam.

LordByronUK · February 15, 2021

sorry, what do you mean by giving it turns?

Herbie · February 15, 2021

1 hour ago, LordByronUK said:

sorry, what do you mean by giving it turns?

You need to push the cable through the ferrite bead and bring it back on itself and push through again etc., the more turns you can get, the better, like so:

EDIT: I always thought the more turns, the better, but I've just come across this text, so maybe just two turns will be enough:

Typically, two turns of the cable are placed through the ferrite bead. The impedance provided by the bead is approximately proportional to the number of turns squared; two turns provides four times the impedance of a single turn. When implementing more than two turns, the series impedance per turn rises to a high enough level that the parasitic capacitance between the cable segments shunt energy past the series impedance created by the bead. The shunting of the undesired signals through the parasitic capacitance reduces the effectiveness of the ferrite bead to less than would be if only two turns were employed.