how do I know if my transformer is blew? Help

[Servantez]

yesterday when I turn on my RM I realize that I didn't hook the head up with the speaker. But I turn the head off right away with out pluging the guitar in.
Now the amp still works fine but I have only tried it in low volume. So I guess my question is there a way that I can tell if I have damage my amp or not.

 

[Anonymous]

As long as there was no signal..ie playing your guitar. You should be alright and it was not a long time.