[Amps] HV transformer buzzing!! Help Please

[Tom W8JI]

Van,

Before you do anything I strongly suggest you findout what 
the deal really is.

Either build a long accoustical listening tube, push on the 
choke, transformer or chassis, or unbolt the iron from the 
chassis and see what happens when you lift it off the 
chassis a bit. Tightening a few screws won't hurt, but stay 
away from doing thing that might tear the thing up unless 
you have no other resort.

I know the mjority are resigned to the fact it is something 
in the transformer loose, and it could well be, but the hum 
you describe is very common even in a tight transformer when 
it is on a steel chassis or near a steel cabinet. 
Especially watch the choke, because chokes have intentional 
air gaps in the core that cause very high levels of flux 
fringing.

Although it might be something else, I'd look at the choke 
before anything.

73 Tom