SBE-33 Repairs -
I looked on Google for an hour and gave up and here your got the info
right
there - Well anyway I was lazy and tried to order the cap - you know the
drill - gotta order through the distributors - called several - all say
minumum order required - 4 weeks delivery -
So I took your suggestion and tried rebuilding it - didn't have the exact
cap in the junkbox but had several that same physical size - the hardest
part was getting that little bugger out of the rig!
Took it apart and your right - there where several places where RF had
punch
some holes in the Mica - pretty small but you could see it without a mag
glass - Replaced the sheets and borrowed a friends digital cap meter to
check out the range - re-installed and now it tunes correctly -
Interesting design - I wondered why they would use a padder cap for final
tune - guess it was the only way to get 700 pikes in such a small space so
you can tune a wide variety of ants - if you were going to use this with
an
amp you could get away with a small vairable with 360 pikes or less.
Overall the whole TX side was designed for low level duty cycle - typical
SSB. If someone tried RTTY on this thing I have no doubts it would blow up
in 10 minutes - The design was ahead of its time in the early 60's. No way
this 42 year old radio can keep up with today's jap rigs - still it works
well enough to use everyday on 40 and 80.
The filament situation still bothers me - in the 60's tubes were 90 cents
each, gas was 35 cents a gallon and electricity was 2 cents a kwh. Ah the
good ol days!
Today, its different and I want those tubes OFF when I spend time
listening
on the bands - but I'm like you Lynn, hate to drill holes and ruin a nice
piece of equipment.
Then it came to me - if I could find a 10k pot with a switch, I could
replace the Mic Gain pot and turn the Filaments ON/OFF with the Mic Gain
control. Only need Mic Gain when the transmitter is ON anyway so it makes
sense and I don't have to drill a hole for a toggle switch.
So that's the next project!
Thanks for all your help! - Biz WDØHCO
Great! Gives me some encouragement in my Knight T-60 project!
Lynn, W7LTQ
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