Is it possible to program an airport express to switch of the wifi at night ? Without physically switch off the router it self and that the LAN keeps working.
No - there is no "off" configuration option
You could theoretically put it one a timer but I'm not sure of the implications vis-a-vie power spikes.
The best that you can hope for is simply not allowing wireless devices to connect say....from 12:01 AM to 8:00 AM......but the wireless signal will still be "on".
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