[Boatanchors] Globe Scout 40A

[L L bahr]

Steve:

One last thing.  Both variables (loading and Plate tuning) are the same cap.  The plate tuning one has high voltage on it.  The loading cap has very little voltage on it unless your SWR is high.  I'm telling you this so if the broke cap can be aligned enough to at least not short out put that one in the loading position and the really good one in the plate position.  But again, if you can get the shorting cap to not short out, I'd bet it will work just fine in either position.

Lee, w0vt

----- Original Message -----

Steve,

I think the bottom line is your capacitor is not aligned properly.  (The rotor plates are not spaced equally between the stator plates).  I am almost certain this is your problem. I bought a new 40A as a kid and never had a problem, so I know the spacing is tight but it will not arc if the capacitor is in good shape.  I recently in the last 4 weeks had the sam issue as you while restoring a 65.  In my case the capacitor was really bent beyond repair.  I was lucky enough to find a replacement but it too was misaligned. Very carefully using a VOM while bending the plates, I was able to get the capacitor so there were no longer any shorts as I rotated the rotor.  Since then I have used the Globe Scout 65 daily without a single arc ever occurring.

Now for a replacement.  First try and repair yours as I did to my damaged replacement cap.  If that works, fine, you are done.  Secondly if you can't do the repair, then just maybe you might get super lucky and find a replacement out of a junker.  I personally think this will most likely not happen unless you get super lucky.  If I was going to have to replace the cap with a non WRL cap here is what I was going to do.  As you are aware the two mounting taped screw holes for the WRL cap are not in line with the tuning shaft but rather slightly down on either side of the tuning shaft.  Until I found a usable exact replacement,  I was going to take an easy to get 430 pf air variable from Peebles Originals and then bolt a 1/8th inch aluminum plate to the Peebles capacitor with flush mounted bolts recessed into the aluminum adapter plate. Then I was going to mount the adapter plate housing the new air variable to the front panel with two tapped screw holes mating up with the front
  panel mounting holes.  There is plenty of space behind the front panel for all this to happen.  I was going to use a 430 pf cap rather then a 365 pf cap as it would give me more range and there is little size difference or cost between a 365 pf and 430 pf cap.  This adapter thing could easily have worked out and from the front panel, you would never know anything like this has been done to your rig.  You would have no extra holes in the rig and the new cap would work just fine.

But again,  I know the spacing is really tight on the original cap, but if it is in alignment, it will not give you any arching problems.  I realize this is hard to believe, but I have had enough experience with many Globe Scouts to know the original caps are perfectly suitable for the rig.  Granted not much to spare but they won't arc if spaced correctly.  Just go in there and try and fix the old cap.  Put an ohmmeter on the cap, have it wide open, slowly close it until the ohmmeter shows short, then take a small blade screwdriver and slightly move each rotor plate one at a time to see if the short goes away.  Then this is the plate out of alignment.  Then slightly really bend it.  Now move the rotor in again a little more and if the thing shorts out again go through the same process.  I was lucky enough to finally get the cap to never short out anywhere.  Once this happened I never had an arcing problem while using the rig. 

Good luck.  Hope this helps you out.

Lee, w0vt
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