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Re: Topband: Topband SB-1000

To: "topband@contesting.com" <topband@contesting.com>
Subject: Re: Topband: Topband SB-1000
From: Jim Murray via Topband <topband@contesting.com>
Reply-to: Jim Murray <adkmurray@yahoo.com>
Date: Sat, 19 Dec 2015 19:16:09 +0000 (UTC)
List-post: <topband@contesting.com">mailto:topband@contesting.com>
"It might be something else, but  I would bet the contact on the 160 padding 
capacitor is burned off. This is what the anti-corona washer reduced. Heath 
did not use that washer.

It arcs there when the loading cap is too far closed (too much grid current) 
for the amount of drive on higher bands, or if the antenna should become 
grossly mismatched when at high power on bands other than 160.  The worse 
band for arcing the 160 padding contact is when on 80 meters."

Had a chance to do some eye ball/continuity checks today.  All contacts on 
bandswitch check out ok.  Except, on the last wafer towards the rear one of the 
lugs that hits on 160 only position has nothing on it.  Some solder but nothing 
connected.  Contacts ok etc. but nothing soldered to the lug in that position.  
Is this possibly where a capacitor once lived?  I have the schematics and 
diagrams and will have to go over all the wiring.  One other oddity I see is 
that there is a black wire coming out of the enclosure in front of the 
bandswitch that is folded over and not connected to anything.  Appears to have 
been at one time connected to a ground lug at the plate variable cap fixture on 
the front panel.Thanks,jimk2hn  
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