[Hallicrafters] Contact Cleaners & other tales

[lardiere at ix.netcom.com]

All,

For what it is worth, I just finished refurbishing two Swan 500CX's, a Swan 500, and a Swan 350.  I sprayed DeOxit D5 sparingly on all contacts, including the high power switch and the oscillator wafers and the relay contacts (using a standard business card as a swipe).

There were zero problems after doing this.  No self oscillations, etc.  No arcs.  Everything seems to work fine after alignments.  I really like these Swans, although the finals are a bit pricey.

I have never had problems with it on my Hallicrafters gear, also.  I also used it successfully on two Henry HF amplifiers.  

However - I did have a problem with using it on the local oscillator on a Galaxy V - the bandswitch had a plastic band that tended to retain the DeOxit - it could not dry out.  So - I am very careful to be sparing in applying any contact cleaner to HF oscillators.  A Q tip is one way of applying it to the metal, not the insulating wafer.

But I just sprayed away on the Swan switch sections with no problems.  Your mileage may differ.  I think Cramolin and DeOxit are somehow related historically.

73,

Rocco N6KN

-----Original Message-----
From: TC Dailey <daileyservices at qwest.net>
Sent: Jul 18, 2005 7:50 AM
To: Hallicrafters at mailman.qth.net
Subject: [Hallicrafters] Contact Cleaners & other tales

Back when I worked in the avionics industry [sic], we used some stuff called CRAMOLIN... yeah, we thought it sounded bad, too... it's resembles sewing-machine oil, and is not only a contact-cleaner, but also an enhancer.  Story from Cramolin was that it left a molocule-thick layer, which actually conducted.  I must admit - nothing cleaned & resurrected old Narco and King radios better, AND it didn't dry out after a while.   BUT - CAVEAT EMPTOR!!!!!!

The stuff conducts at higher-power RF!  I cleaned the bandswitch on a SWAN 500C, and that sucker took off and "flew".  Self-0scillated on 15m and 10m... [they don't call 'em SWAN's for nuthin'!]   Cramolin is still around (developed for high-flying B-47's and B-52's!), but ONLY use it on RECEIVING gear!

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