[Amps] Titan 425 power transformer question

[Jim Brown]

On 6/6/2011 1:17 PM, Carl wrote:
> It sounds like you may have an open cap in the string.
>

YES!  You'll also be getting reports of hum (or a buzzy CW note).

Don't try testing by voltage measurements. You need an old fashioned 
analog VOM, like a Simpson 260 or even a cheaper equivalent.  Let HV 
bleed for a long time, then open it up and use the middle Ohms scale to 
measure resistance of each cap in the string, first in one direction, 
then reversing the leads. What you're watching is the charging current 
each time you reverse the leads, and you want to see a lot of meter 
movement (that is, very low resistance readings that gradually decay to 
high resistance readings.  Measure them all (no need to write numbers 
down) and see what they look like. When you find one that doesn't move 
as much, that's the bad one.  It's common to find one or two bad ones 
while the rest are just fine and have plenty of life left in them.

73, Jim K9YC