Picture break up on freeview channels

[Leon1]

My TV pictures breaking up and freezing on Freeview channels when co-axial aerial leads connected through YouView+ box. BT channels coming through the Home Hub are not affected. Some Freeview channels such as Sky News are affected worse whilst the HD channels are completely unaffected.

Our house is on a hill and TV reception through the rooftop aerial is good with a strong signal.

When the TV is connected directly to the aerial socket there is no problem and the aerial leads are quite short and undamaged.

As an experiment I disconnected the Youview box and connected my old Humax DVR (which worked OK when I replaced it with the YouView+ box last year) and the problem remained although there was more freezing than break up.

I’m completely baffled as to how to fix the problem so any help would be appreciated.

[zulu17]

Hi @Leon1 

Possibly  interference between the aerial cable and the HDMI cable when using the  YOuview or Humax PVR ?  Does the Youview box record  a clean recording from the Freeview channel. ?

Freeview channels are transmitted  from  up to 8 or 9 multiplexes  which are at different frequencies so signal levels and interference may vary depending on mux.

[Leon1]

Thanks for your help and yes, the Youview box recorded the picture break up as seen on the screen.

I should have said that the problem only started after I had a CCTV system installed a few days ago. The CCTV DVR is located next to the same power point as my TV set and YouView box. I couldn't work out how the CCTV DVR could affect the YouView box because the picture break up continued even after I cut the power to the CCTV DVR.

My Samsung TV has two HDMI slots and when I re-connected the YouView box a few minutes ago without connecting the CCTV HDMI lead to the second slot the picture break up seems to have gone. Over the last few days I've tried so many combinations trying to isolate the problem but without success. I don't think I tried to see what happened by just disconnecting the HDMI lead connected to the CCTV DVR, so maybe your suggestion was correct. In any case thanks for your help.

[DavidM]

Hi @Leon1 and welcome to the community.

Sorry you're having problems with picture break up. @zulu17 has posted some great advice but you might also want to consider an attenuator which should help. You can pick one up cheaply at your local TV store.

Cheers

David

[Leon1 · Accepted solution]

Hi DavidM

Thanks to you and Zulu17 for the tips and the problem is now solved. Once I reconnected the Youview box and disconnected the CCTV HDMI lead from the TV set the picture was fine - no more break up. It was news to me that there are EMI issues with HDMI cables. I'm not so up to date on tech (ie. post 1984!) but I found the following website interesting although you're probably familiar with it https://interferencetechnology.com/hdmi-cables-emi/

[DavidM]

Hi @Leon1 ,

Thanks for getting back to us. @zulu17 advice was perfect (kudos to you). I'm really glad you got this sorted. I've learned something new myself with this.

All the best

David