TV on & off?

Hello

We live in a high rise flat using a communal aerial.

We use Bush DFTA7 for freeview.
The TV is Pilips Model No. 2SPV808/07
S AA A9EF A4 D9 C4 F5 FF E5 39 86

After turning on the picture and sound disappears for about 30 seconds, then automatically reappears until the next time it disappears. at intervals of about 2 minutes.

Would this be the fault of the freeview set or TV?

Thanks for your help.