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'scratchy' audio pot on K2??

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Allan Taylor

'scratchy' audio pot on K2??

I am about to purchase a very early K2 for use almost entirely in the
field. The potential seller mentioned
that his K2 has a scratchy audio pot but also said that the cure was
well known. I searched through the
Elecraft site, etc. and came up dry. Could someone point out to me
where the 'cure' is located so I can assess
my options? Thanks!

Please reply off-list to [hidden email]

--
73 Allan K7GT
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Stephen W. Kercel

Re: 'scratchy' audio pot on K2??

Allan:

Use DeOxit spray. Available at Radio Shack.

73,

Steve Kercel
AA4AK

Allan Taylor wrote:

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Mark Bayern

Re: 'scratchy' audio pot on K2??

In reply to this post by Allan Taylor

Try <http://www.elecraft.com/Apps/K2_AF_pot/K2_AF_gain_app_note.pdf>

You should probably check out all the K2 app notes.

Mark AD5SS

On Fri, Feb 12, 2010 at 9:00 AM, Allan Taylor <[hidden email]> wrote:

> I am about to purchase a very early K2 for use almost entirely in the
> field. The potential seller mentioned
> that his K2 has a scratchy audio pot but also said that the cure was
> well known. I searched through the
> Elecraft site, etc. and came up dry. Could someone point out to me
> where the 'cure' is located so I can assess
> my options? Thanks!
>
> Please reply off-list to [hidden email]
>
> --
> 73 Allan K7GT
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>

Don Wilhelm-4

Re: 'scratchy' audio pot on K2??

In reply to this post by Allan Taylor

Allan,

Add the Alternate AF Gain wiring (see application notes on the Elecraft
reflector), and since you must have the front panel board out of its
metal panel to make that wiring change, replace the AF Gain pot at the
same time. A bit of work, but not really very extensive.

73,
Don W3FPR

Allan Taylor wrote:

> I am about to purchase a very early K2 for use almost entirely in the
> field. The potential seller mentioned
> that his K2 has a scratchy audio pot but also said that the cure was
> well known. I searched through the
> Elecraft site, etc. and came up dry. Could someone point out to me
> where the 'cure' is located so I can assess
> my options? Thanks!
>
> Please reply off-list to [hidden email]
>
>
> ------------------------------------------------------------------------
>
>
> No virus found in this incoming message.
> Checked by AVG - www.avg.com
> Version: 9.0.733 / Virus Database: 271.1.1/2683 - Release Date: 02/12/10 02:35:00
>
>

dw-4

Re: 'scratchy' audio pot on K2??

In reply to this post by Allan Taylor

Hi Allan,
My audio pot started acting finicky after only a few weeks of use on the
K2.
I swapped it with the RF gain pot.
I adjust the RF gain only a tiny amount anyway in normal use.
Check first to make sure they are the same value.
Some K2s may not have had identical pots.
Also, you'l want to do the Signal Strenght calibration afterwards.

Hope this helps
N1BBR

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Don Wilhelm-4

Re: 'scratchy' audio pot on K2??

The AF Gain pot is different than the RF Gain pot in all K2s. The AF
Gain is an audio taper while the RF Gain (and the other 3 pots) are
linear controls.

With that swap, I would expect both the AF Gain and RF Gain controls to
behave "funny".

73,
Don W3FPR

dw wrote:

> Hi Allan,
> My audio pot started acting finicky after only a few weeks of use on the
> K2.
> I swapped it with the RF gain pot.
> I adjust the RF gain only a tiny amount anyway in normal use.
> Check first to make sure they are the same value.
> Some K2s may not have had identical pots.
> Also, you'l want to do the Signal Strenght calibration afterwards.
>
> Hope this helps
> N1BBR
>
>
>
> ------------------------------------------------------------------------
>
>
> No virus found in this incoming message.
> Checked by AVG - www.avg.com
> Version: 9.0.733 / Virus Database: 271.1.1/2683 - Release Date: 02/12/10 02:35:00
>
>

dw-4

Re: 'scratchy' audio pot on K2??

In reply to this post by Allan Taylor

Thanks Don,
Thats good information.
With that understanding , wisdom would dictate that the AF pot be
replaced with its original.
I won't bother to change mine however as its working beautifully as is.
It made me wonder what percentage of K2 builders have mistakenly swapped
those two pots and don't even know it. :)

The AF Gain pot is different than the RF Gain pot in all K2s. The AF
Gain is an audio taper while the RF Gain (and the other 3 pots) are
linear controls.

With that swap, I would expect both the AF Gain and RF Gain controls to
behave "funny".

73,
Don W3FPR
--
[hidden email]

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