Silence extension ringer at certain times?

[Cerrado]

Suppose you don't want to be disturbed on your bedroom extension line if a call comes in in the middle of the night.

Is there a phone or accessory where you can disable the phone ringer (or even the extension line) automatically during set hours?

[imjolly]

I have a panasonic 8622 where I can set it to night mode and stop the ringer during set times

[Cerrado]

Thanks for that suggestion - I shoud have said, what I really need is a really simple desk phone (i.e. where the handset has no buttons), or a device that controls the line (like the discontinued LineLok).

A cordless like that Panasonic would be great for me, but this is for a person with Alzheimer's who would has trouble with any but the simplest devices.