SB-221 just died

[Jan Sluchak]

Yes my SB-221 just died, and I may have helped keep it down.  I have
been using my 221 with my 1000D for about a year with no problems.
Usually get about 900 to 1000 watts out on 20 with 100 watts drive.  A
couple of days ago, while tuning up the amp started making some
screeching noice around near what appears to be the  Tune and Load
tuning areas.  I backed off the power and the amp appeared to catch,
inother words put out RF after a certain amount of power was applied.  I
never touced the drive knob.  Now the amp keys and the relay pulls up,
but no rf is passed.  My High Voltage is good.  I looked inside for a
burned wafer switch or burnt caps and resistors etc.  The only thing I
cam accross was blackened resistors (4.7ohm 2 watt) in the parisitic
chokes.  The resistors had appeared to have shrunk over the years and
they looked toasted a little.  they both tested at 55 ohm which is wrong
for the value according to the colors, as they should be 4.7 I think.  I
wound new parasitic cage at the proper diamenter and placed new metal
film resistors inside of the choke.  4.7ohm @ 2 watt.
I now get no output and feel I am digging a deeper hole.  May I not use
metal film resistors in the rf path?  What have I dont to kill this
unit.  Also, the swr is terrible when the unit is on.  When it is off,
it passes rf power very accurately from my 1000D as checked on my Bird
43.
What have i done and what can I do??
Thanks for any help.
Regards,
Jan Sluchak  N6YV

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