[Hammarlund] BBOD report

[Al Parker]

Hi all,
    I've finally gotten back into an SP-600 of mine that I started over a
yr ago, and have just completed the RF deck.  Thought a report might be of
interest.
    There are 20 BBOD's in the RF deck, about 40% of the total in the
whole rcvr, so it's a significant area for time, plus it's a bear to
remove & replace to do the actual work.  I've spent several days working
on this RF deck, usually not more than 2 hrs at a sitting, but more than
once/day.
    After removal of those 20, 13 were measured to have 1 megohm OR LESS
resistance, at only 100vdc applied.  The others 7 had about 2 meg at
250vdc.
    In both the first and second RF stages, both dropping/decoupling
resistors in the plate line were open.  The 2 in the screen line were OK
in stage 1, but one was open in stage 2.
    Other resistors measured within 10% of spec.
    I'm presently ready to re-install this unit & get on to some of the
other enjoyment awaiting me in this great rcvr.  I had redone the panel
over a yr ago, and replaced the BBOD's in the IF cans since that time.
Now I'm gonna finish the whole job before I get sidetracked again (I
hope).
73,
Al, W8UT
New Bern, NC
BoatAnchors appreciated here
http://www.thecompendium.net/radio/
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