So how does one know if the band switch is good or bad for RF? My band switch
obviously had some burning. No contacts are missing. But the switch plate is
definitely etched. I cleaned it with some alcohol, and got lots of dirt off of
it. I have not reassembled yet to see if that changed anything. The ceramic
wafers have no carbon tracking. But like I said the metal plate definitely
looks to be etched. Guess I need to try it after the cleaning. Is there a
decent contact cleaner I can use to really clean the switch up that is not
detrimental to RF?
-- Ken. N3KF
Sent from my Android tablet
-----Original Message-----
From: amps@n3kf.org
To: amps@contesting.com
Sent: Tue, 27 Oct 2015 8:50 AM
Subject: [Amps] Heath SB1000 no power out on 10 and 15
Hope this is not a repeat from me. I have an SB1000 (AL80A clone) I built back
in the 80s. Lots older and with back issues it is hard to get around and work
on now. I have the original and a new tube and the amp acts the same. On 160
through 20 meters all seems to be OK. However, on 10 and 15 meters there is no
output. The oddity is that the meters show plate and grid current just like
normal and the tube heats up. I figured this is an easy one and I smoked the
band switch. Other then some carbon tracking, the switch looks good. Cleaned it
up some, but no change (really did not expect it since the output does not
exists). The PO meter of the amp does not show any power on any band. Another
problem, but I think I have read about this one. So is the no power out a
common problem? If not, I guess I got to dig into it. When I said I get grid
and plate current, that is with low power since obviously if this is not
putting power out, that RF must be dissipating somewhere! Thanks f
or any thoughts.
-- Ken N3KF
Sent from my Android tablet
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