thought you might like to know that the century 22 is now back in
operation
after 2 months off air !
The fault was actually a combination of two things,
1) there was a lot(i mean a lot)
of old flux on the back of,and front of the PA board.This was causing
problems around the first transisitor ,near the input.when going to transmit
it's collector went wild !
2)The PA transistors were faulty !,i had checked them with a VOM and
they
appeared ok,
also when the power was turned right down they seemed to work,anyway i
finally replaced them with
a new pair of 2sc1969's cleaned all the pa board with solvent( some sort of
alcohol,can't spell it !!) and put it all back together and hey presto it
worked.
I never dreamed that the old flux would cause such a problem.That was
the
main cause and probably caused the pa transistors to go faulty,(they
weren't open circuit !)
73's de Bill G4KKI
Member of R.I.G. RSARS.1596..FISTS 7709.
Web site at http://www.g4kki.freeserve.co.uk/
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