On Feb 2, 2006, at 5:56 AM, David C. Hallam wrote:
> If you check in any Handbook of Chemistry and Physics, you will see
> that
> there is very little absolute difference in conductivity between
> copper and
> silver. There may be positive attributes to silver plating when used
> in
> radio circuits, but an significant decrease in resistance isn't one of
> them.
>
> BTW - Do you know that during WWII, silver was used for the electrical
> wiring in the Hanford, WA plant for the production of plutonium.
> Copper was
> needed for the war effort and the US Mint had a large quantity of
> silver.
Indeed. I have a WWII 25uH, BC-375 roller coil that is made with #14
solid Ag wire.
> After the war the wiring was replaced and the silver returned to the
> Mint.
> For the same reason most 1943 5 cent pieces were made of silver rather
> than
> nickel. After the war, these coins were pulled from circulation.
>
> History lesson for today
>
> 73
> David
> KC2JD
>
> -----Original Message-----
> From: amps-bounces@contesting.com
> [mailto:amps-bounces@contesting.com]On
> Behalf Of R.Measures
> Sent: Thursday, February 02, 2006 5:32 AM
> To: peter.voelpel
> Cc: 'Amps'
> Subject: Re: [Amps] Pi vs Pi-L
>
>
> Thanks for saying it, Peter. One of the more interesting things about
> VHF is that a conductor's surface area has more to do with Q than does
> it's S/cm^3 conductivity. For example, at 1Hz, Ni-Cr alloys have about
> 50x more resistance than Ag or Cu, however, at 50MHz, they only have
> about 5.5x more resistance. This realization is important when
> designing a low-Q VHF suppressor -- i. e., one that will substantially
> reduce VHF amplification in an HF amplifier by reducing the VHF Rp seen
> by the anode. (Rp = parallel-equivalent R) .
> end
>
> On Feb 1, 2006, at 10:48 AM, peter.voelpel wrote:
>
>>
>> Mike,
>>
>> How much better will be Q and how much less will be losses
>> by silverplating HF tank components?
>> On 2m amps I measured no difference at all before and after plating
>>
>> 73
>> Peter
>>
>> -----Original Message-----
>> From: amps-bounces@contesting.com [mailto:amps-bounces@contesting.com]
>> On
>>
>> Silver plating of the tank components will help Q and reduce losses as
>> well.
>>
>>
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>>
>>
>
> Richard L. Measures, AG6K, 805.386.3734. www.somis.org
>
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>
>
>
>
>
>
>
>
Richard L. Measures, AG6K, 805.386.3734. www.somis.org
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