[ARC5] Silver refurbishment

[Michael Hanz]

Actually, Bobby Barmore, a member of the original "boatanchors at the 
porch" group and a broadcast engineer, was the one who related the 
problems of Tarn-X and other dip polishes creating an etched honeycomb 
effect on the silver, exposing more silver area to the atmosphere and 
accelerating _subsequent_ corrosion.  I simply confirmed her results 
using my own microscope and tests.

The other thing to remember is that there are two different kinds of 
tarnish affecting silver wire inductor coils - silver sulfide and silver 
oxide.  Silver sulfide is more prevalent in parts of the country due to 
higher concentrations of hydrogen sulfide, and is not a very good 
conductor except at higher temperatures than normal room temperature.  
So, avoid eating broccoli or hard boiled eggs around it.  (Okay, just 
kidding, but keep your ARC-5 transmitter out of sewage treatment 
plants...)  Tarn-X and the like doesn't seem to do much good on the 
silver sulfide when I tried it on some sad samples, but Wright's Silver 
Polish will do a decent job on either type of silver corrosion - at 
least in my experience.  The downside is that it takes more effort, but 
the results are worth it...

The Wikipedia entries are probably worth perusing:

https://en.wikipedia.org/wiki/Silver_sulfide
https://en.wikipedia.org/wiki/Silver_oxide

- Mike   KC4TOS

On 12/23/2020 9:25 PM, David Stinson wrote:
> It is true that silver oxide is a good conductor.
> The problem is that the oxide on our stuff isn't pure;
> over the years, a great many micro-contaminants
> mix with the oxide and you end-up with
> a lot of intermittent contact while rolling
> the coils or operating the switches.
>
> For years I've used Wright's Silver Cream with
> good results.:
> https://www.amazon.com/Wrights-Silver-Cleaner-Polish-Cream/dp/B07VQM78DM
>
> Mike Hanz investigated the "just dip it" products
> years ago. They were destructive to the silver, leaving
> microscopic pits.
>
> GL OM ES 73 DE Dave AB5S
>
> On 12/23/2020 8:12 PM, Brooke Clarke via ARC5 wrote:
>> Hi Ken:
>>
>> It's my understanding that Silver oxide is an excellent conductor, so 
>> other than cleaning there's not much to do.
>>
>

-- 
Michael Hanz - KC4TOS

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/arc5/attachments/20201223/1abc67a9/attachment.html>