When I was in the military, we worked on LTV receivers that used what we called
"Blue Grease". It was, obviously, blue and conductive. I even laid a short line
of it on a glass plate and measured the resistance, which was remarkably low.
That being said, when applying it to the inductor, the very tiniest amount was
needed. Certainly not the amount in the photo. And it was only applied to the
contact points of the inductor and to the hinge pin of the wiper. (the
inductors were flat and wound like a Nautilus shell). My concern would be if
the grease was in fact conductive and if so I would remove most of it. If it is
not conductive I would remove all of it and find some that is.
Clint - W5CPT
----- Original Message -----
From: Gary Smith
To: amps@contesting.com
Sent: Sunday, November 25, 2007 4:11 PM
Subject: [Amps] Roller inductor & wiper "grease""
I just bought a transmatch and the capacitor was extremely loose but
I figured I could repair it, it was loose enough that the weight of
the rotor would cause gravity to spin it downward.
I opened up the tuner and found what looked like black grease on all
the friction points of the rotor. I disassembled it, found the
friction clutch to govern the tension on the rotor and made all free
of grease and now the capacitor works perfectly with good friction.
I saw a similar grease on the inductor at the same contact points.
The seller said he hadn't worked on it and the capacitor seemed to
hold for him and I took him at his word and I left the stuff not
wanting to backward engineer the design of the thing.
Now I'm finding when tuning on 10 meters that with the tuner active,
higher power causes the reflected power to jump all over the place
but when running straight through & bypassing the transmatch there's
no jumping of SWR at all.
I was thinking when I first saw the "grease" that it was there from
the beginning but now I'm thinking it was added but a previous owner
to make the mechanics works more smoothly without regard to RF issues
that would bring.
Below is a photo of the inductor & wiper asembly. You can't miss the
grease or whatever it is on the components.
http://doctorgary.net/nye_inductor.jpg
I am thinking I wasn't told the whole story when I bought the
transmatch. So here's some questions for the group;
Is the black grease you see here something that comes on some edge
wound inductors?
If as I suspect it is something applied by someone before me, what
would be an effective way to remove this grease? I hate to have to
disassemble the whole thing but will if that's the only way.
I was thinking about putting rags in the bottom to keep it clean
after spraying the greased parts with starting fluid which would
surely degrease.
Not sure what if anything should be applied to the contact surfaces
after all the grease is removed. Or does this greasy stuff actually
belong there?
Thanks,
Gary
ka1j
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|
