[R-390] Tuning the IF Second Question Stuck Slugs

[w9ya at arrl.net]

Hey gang;

A comment about the "magic powder" mentioned in the posting below:

Um, there are many kinds of powders that magicians use to rub into decks.
Be sure to get the stuff called "fanning powder". Why ? - Because some of
the stuff is designed to make the cards stick to one another, and that
would make life worse for keeping slugs loose.

Very best regards;

Bob
w9ya

> Paolo Gramigna asked
>
> Now, to the second question: the IF lugs are sometimes stuck in place,
> and
>  I am afraid to break them. What is the best de-stucker and lubricant
> for
> them?
>
> _______________
> Paolo,
>
> This question comes up often.
>
> Watch the other mail and see what other advice you get.
> Do not jump right into this problem.
>
> The answer has three parts.
>
> Do you really need to get the slug unstuck?
> How do you get the slug unsuck?
> What do you lubricate the slug with once it free to keep it from seizing
> up  again.
>
> Then we throw in a whole bunch of stuff not to do.
>
> Go through the alignment and just leave the stuck slugs alone. These
> receivers are over 50 years old and received lots of regular service in
> their  day.
> No reason at all to believe the stuck slug is not set at almost its best
>  position. Align the receiver and see what the signal to noise ratio is.
> Then  try
> some tube swapping to get the ratio up a little better.
>
> If and only if the receiver will not get you better than 15:1 signal to
> noise  ratio and you can isolate the loss down to the stage with the
> stuck slug,  then
> worry about getting it to adjust.
>
> Worry not if you break the slug. A broken slug can be replaced. A real
> concern is twisting the core inside the can and breaking a wire between
> the  winding
> and the terminals inside the can. Pull the cover off the transformer so
> you  can see your core and coil winding before twisting very much on the
> slug.
>
> Never, never, never use WD40. The long term effects are more trouble
> than you  want.
>
> There is no magic solvent that we just "know it works".
> Apply some rubbing alcohol and take the next day off while it all soaks
> in.
>
> Good lights and a needle may help you dislodge some gunk. Large amounts
> of  air may help blow some crud out of the tube and help free the slug.
>
> Use a metal hex key in the slug to turn it. You may have to move the top
> slug  a bit so the key will drop through the top and bottom slug to turn
> the bottom  slug.
>
> Heat the metal key with a solder iron to "melt or soften" some of the
> gunk.
>
> Hair dryers have been used to good effect for this. Gently warm the
> whole  slug tube with the transformer cover off and watch the resin
> melt. Let the  heat
> soak through the tube a bit before trying to turn the slug.
>
> Once you get the slug free what do you lubricate it with?
>
> There is a magic white powder for this. If you are a radio guy you buy
> it in  big packages from secret sources. Other wise you acquire a life
> time supply  from a local shop that sells magic tricks.
>
> The stuff is a power magicians rub on their card decks for magic acts.
> Someone will surely toss in a name for this substance here.
>
> Until you locate some "lube" just run the slugs out of the tube, clean
> them  up as best you can and install them back into the tube.
>
> Good luck with this
>
> Roger AI4NI
>
> P.S. I hate when I fat finger a function key and post half a mail. Sorry
> Fellows.
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