On Wednesday, 10 August 2016 16:25:29 UTC+1, Capitol wrote:
Has anyone experience of these wired systems . I've been looking at
installing a 2 x 90 degree camera, white led lit with 8 x 8in 4 x 3
format white/beige coloured monitor system with intercom facility and
with electronic/keyfob unlocking. I can't find a system that goes beyond
6 x 7 inch monitors 16 x 9 format. What is the limit on the number of
monitors?

Is this for multiple flats (multiple call buttons) or within the same house? There is usually no limit on the total number of monitors, but usually only one can be active at the same time.

You may be better looking at audio-only door entry system and using a separate video splitter to feed individual monitors (or feed the CCTV video into the TV distribuition systyem)

Owain