How to generate an RSS feed for a site that does not support it?

Question

RSS

What are some good free services? Recently I came across a very good service, moreover, it is updated every few hours or more often, but, unfortunately, I did not save it. I've been looking for a few hours now.
I know about such services:
1) feed43.com is probably the best option from the list. Free, customizable, updated every few hours and pulls 20 news. Of the minuses - it is not always possible to set up the tape properly.
2) fetchrss.com is a very convenient visual editor, but on a free plan it is updated once a day and can only parse 5 posts at a time
3) feedfry.com- does not allow you to customize the feed, offers from several automatically generated options, is updated every 8 hours and takes 10 entries at a time
4) politepol.com - free version downloads only titles, 20 feeds, instantly
5) createfeed.fivefilters.org - too complicated for me :(
6) feed.exileed.com - for social networks: VKontakte, Facebook, Google+...
7) urlooker.com - free plan parses every 24 hours, maximum 2 pages - haven't tried
8) feedity.com - only paid tariffs
there are some other similar paid options, they were not indicated