On 31/01/2018 21:03, Chris Green wrote:
Has anyone come across a video door entry system which uses an
existing television for the display? My M-I-L wants a door entry
system which allows her to see the visitor before unlocking the door
but any 'extra' display hardware really isn't practical.

Yes. It is easy almost all of them even the cheapest nasty ones from
Aldi/Lidl produce a composite video out and a mono sound channel. The
only snag is that you have to change from TV to another input.
It would make *much* more sense to be enable to interrupt the TV
display, it's always on and the *important* thing is that it's when
M-I-L is in easy chair in front of the TV that it takes her a long
time to get up and get to the front door.

Any ideas anyone?

The only snag is that she will have to press Aux AV input and remember
to set it back to TV again afterwards. A TV that did PIP preview would
really be ideal for this. Check the one you intend to buy does produce a
composite video and sound output and you should be fine.

The odd one uses its own quirky LCD monitor at non-standard size/rates.

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Regards,
Martin Brown