A while back I posted questions concerning re-winding plate chokes and such
for the SB200. Here are the results in case anyone is interested.
The plate choke was re-wound with 26 ga. enameled wire (from our
friendly Ratshack)
the filament choke was re-wound with 18 ga. (from same place) .
after all was done and fired up I found everything worked just fine,
maybe even better.
With the pulser keying the exciter and using an Autek WM1 on the output I
got 750 watts PEP on 80-40-20,
650 on 15 and about 600 on 10 mtrs. with 65 watts drive. I noticed what
looked like excessive heating of the parasitic resistors , so I have taken
them out and am making new suppressors at the moment.!!
all in all the results are good.
Someone here wanted me to post my results so this is it.
I also coated the plate choke with Q- DOPE (tm)
It works fine The smaller wire on the fil. choke dropped the fil
voltage about .3 -.4 v ac.now have about 6.25-6.3 at 120 vac in. much
better I think.
Have a good day all. !!!!
carl / kz5ca
P.S. The amp still oscillates on 20 and 40 with no load on the input and
output, but appears perfectly stable under operating conditions.!!!!
I want to look into this further at a later time. right now the amp is
needed for the coming hurricane season.!!!!!
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