18:47 Jul 19 

Very comprehensive and helpful advice.

Paul

12:51 Jul 19 

you can find that sort of thing, if you want to look for it, in connection with TV schedules. The asker will know whether τηλεοπτική ζώνη is contrasted with some other term in Greek, and whether a distinction needs to be made in English...

12:39 Jul 19 

in the text, or whether it's used repeatedly. If it's just a one-off, I'd be inclined to used "slot", because that's the word I associate most readily with "prime-time", "morning", "evening" etc. It's for the asker to judge!
- and if the word "block" is used, perhaps it's best to add some qualifying word ("programming block", "block of programming" - my wikipedia link should give some ideas).

12:33 Jul 19 

where everything is very tightly defined, yes, there may be that distinction between "block" and "slot" - but the word "block" can mean so many things in English, you have to be careful how you use it.

10:28 Jul 19 

As Dylan suggests, "block" is used within the industry to refer to a longer period of time than "slot". So a morning/prime-time slot means a slot within the morning/prime-time block.