Just picked up what looks to be all original yba-1. I've never messed around with amps much but i do have some electronics experience and work around electricity all the time (i know how to discharge a cap). This thing hasn't been fired up in years. From first glance: No rectifier tube - kind of a bummer but its one less tube to buy Original tubes - 3x rogers 12ax7 and 1x rca el34 One tube looks like it went spectacularly ( halo of brown around tube socket) Fuse is good 2 prong plug needs to go Almost all solder connections have the nail polish on the connections Question 1: If I was a tech what would I check before firing it up? Question 2: Whats the danger (to the amp) of putting new power tubes in and firing it up?