univox U45 re-tubing and info

[Fed]

I have this old amp that I got free and used for some time but never actualy checked it's history or anything, well now I'm trying to find more info about it and posibly put new tubes in it. I'm not sure it needs them but at least one I looked at had like black burn spot on it.. so maybe...

the amp looks like one in this auction
http://cgi.ebay.com/ws/eBayISAPI.dll...item=897330854

so that's how I figured it was a U45

I'm looking for tubes recomendations and place to get them and any info you have on the amp. It has three inputs (not chanels)
but I'm not sure why or what is the difference between them. Also tremolo doesn't work so if anyone knows how to repair it let me know... it might be related to bad tube or something so I'll probably change tubes first and see if it starts working...

oh according to another auction
http://cgi.ebay.com/ws/eBayISAPI.dll...item=897325127
"The tubes go 12AX7, 6BM8, 6BM8, 6X4" out of whitch I only heard of 12AX7...

If it seems like I don't know much about tubes ... well you guessed it ...

thanks everyone