If I hide SSID how can I connect my device (TV-set) to router? I.e. I need hide SSID and leave this TV-set using my wi-fi. Is it possible?

What is the purpose of making it hidden?
Can you unhide it, connect the tv and make it hidden again?

@erlinden
yes, I suppose

@GreenFirefly
read your TV manual, all the smart TV I have used, have the menu to bind to hidden SSID entering manually the SSID.

And about hidden SSD: are one idiocy, SSID still visible without problem to non-standard "dummy user"...
Indeed, someone who does not know how to scan the surrounding networks correctly
does NOT notice your wifi and maybe sends to you disturbances, because he thinks it's free anyway...

What is the purpose of making it hidden?

It must not be seen by our incoming visitors.

[thought]
I can imagine how welcome these visitors are...
[/thought]