Greetings to the group,
In a recent post to the reflector Dave Kirby wrote:
>Adding more capacitance can be a bad thing. The extra stored energy can
>destroy tubes in an arc. However, I dont want to get into a discussion
>on arcs !!!!!
Steve also added
>Adding more capacitance can also fry transformers with the (Ipeak)^2
>Steve
I have just completed a " rebuild " of a 2500 which involved
replacement of all the diodes in the HV rectifier as well as replacement of the
original Sprague TVL-1770 ( 150uF @ 450WVDC ) filter caps. These caps were
replaced with Mallory computer-grade screw terminal versions. 210uF @ 500WVDC.
This conversion has brought the total capacitance to 35uF up from the original
25uF. I like others have always thought that as far as capacitive filters go, a
little more is usually a little better, yielding less ripple as well as better
"transient response". Was I wrong and do I have anything to worry about with
this conversion? Also just as a point of reference can anyone tell me what
their 2500 reads in plate voltage. My unit is minus tubes at the moment and
reads somewhere between 2250 & 2400 volts according to the built in metering
circuitry.
TNX
Steve
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