You catch Ho-oh at lv 45.
I don't think it's tin tower, it might be Bell Tower. You might not have the Clear Bell and the Rainbow Wing.
ho-oh is on the top of the tin tower
its in ecruteak city its. been renamed bell tower
You need to defeat Clair the Blackthorn City Gym Leader and then defeat the 5 Kimono Girls and then you'll be given a bell and you'll be able to take it up to the top of the Tin Tower in order to summon Ho-Oh in Pokémon HeartGold.
Go to the top of the Bell Tower in Ecruteak city with the Rainbow Wing.
in bell tower
At the top.
it is impossible to reach the top of the radio tower in kanto or jhoto,sorry.
In the top of the battle tower
go to the top.
you go to the top because you get ho oh
it depends on what game you have, in heartgold and solesilver it is on top of the bell tower