Cleaning Wafers

[Garey Barrell]

The problem with Tarn-X is that it chemically removes silver from what 
is already a microscopically thinly plated surface.  ANY "silver 
cleaner" works by removing silver sulfide, (the black stuff,) either 
chemically or mechanically.  Silver sulfide is very nearly as conductive 
as the silver itself, and soft enough to be pushed away by any wiping 
action of a typical switch.  This is why you see a thin, bright silver 
line on a switch blade. 

The danger of ANY cleaning method that calls for Q-tips, probes, brushes 
or any other tool in and around the fixed contacts of typical rotary 
switches in most ham gear is that these contacts are easily "sprung" so 
that they no longer make reliable contact, effectively destroying the 
switch.  The problem with the chemical cleaners is that they are almost 
impossible to remove completely without rinsing thoroughly, which is a 
whole 'nother problem in old electronic gear.  So the chemicals continue 
to work, and any abrasives continue to wear on the contact surfaces.

A small drop of DeoxiT liquid on a couple of fixed contacts, then 
operating the switch to distribute it only where needed, is a far safer 
and more effective method for "working" electronic equipment.   If 
you're entering a "concours" exhibit, then polish away with whatever it 
takes for bright, shiny switch surfaces!

73, Garey - K4OAH
Atlanta

Drake C-Line Service Manual
<http://hr99.home.mindspring.com/R-4C_Servicez/>



Martin Tippin wrote:

> I use Tarn-X, Works beautifully.
>Martin Tippin W0AKG Since 1950
>31 Circle Dr.
>Windsor, Mo 65360
>
>  
>

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