A Dish-500 is -generally- unsuitable for Ku FTA.
Now, there are two schools of though.
#1).
Serious, Dedicated, Reliable:
There are the folks who want the best signal, no troubles from any birds, no matter where they are in North America.
Those folks use a 36", maybe a 1 meter, or possibly 1.2m (4') dish for Ku!.
Those are serious folks and they will be successful getting those signals.
The 36" dish will get 'em going and they won't come back complaining.
#2).
Foolin' around, Braggin' rights, & Goofin' off:
a). a few transponders on a few birds can be received with a 20" dish and a Standard or Universal LNB.
We don't recommend those to beginners because that's ALL they can get!
WhiteSprings and KUIL come to mind.
b). NASA and Angel One are on the Dish 119º bird,
circular.
Those are unscrambled and some folks like 'em to augment their FTA.
Category 1 is real FTA, and the answer you get when asking if a Dish 500 will do FTA, is "no".
But, 2a and 2b are the exceptions.
There is the whole story.