Any SB-401 Hints available?

[James C. Owen, III]

In message Wed, 2 Jul 1997 12:17:00 -0700,
  "Snowden, Douglas" <DSNOWDEN at NCDC.NOAA.GOV>  writes:

> I've been tinkering with an SB-401 and pretty much have it going with the
> exception of
> sort of low output on 20 and 15 meters. Any hints on typical components to
> look
> for that may have deteriorated over time?

What do you call low output? The 401 should put out 90-110 Watts on 80-15
meters and 80-90 watts on 10 meters. To check if problem is before finals or
after look at the grid current. You should be able to get full scale grid
current (1 ma) on all bands except maybe 10 and there you should get at
least .5 ma. If you can't get this on 20 & 15 then tuning of the circuits is
not correct for these bands--do a careful alignment. If you have proper grid
current then problem has to be in the final stage--weak tubes, improper LC
ratio, poor construction, poor neutralization etc. Shouldn't be hard to
find. Remember, alignment has to be done in the correct order, 75 Meters
first and then 40-20 etc. 73 Jim K4CGY