K2 Sn ~700 need upgraded filter crystals?

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K2 Sn ~700 need upgraded filter crystals?

kf4ueo
I have an early K2 with K2SSB that has been mostly upgraded to Rev B. I don't have any issues with my K2 but have always wondered over the years if I need to upgrade the filter/BFO/SSB crystals. I have tended to think however "if it aint broke..." etc. I have done the flatness SSB mod. Is it worth it?
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Re: K2 Sn ~700 need upgraded filter crystals?

Don Wilhelm-4
Your BFO crystals are OK - there was no change.
With the older crystals - sometimes they made fine filters, it was
something like "the luck of the draw" because the motional inductance
was not specified.
I would generally recommend you change them, but as you say, if it ain't
broke, don't fix it.
In every case where I have changed the crystals for an upgrade customer,
there has been an improvement.  When you change the crystals on the KSB2
board, that is a good time to change the capacitors that control the
filter bandwidth - the caps are easier to change while the crystals are
removed.

73,
Donn W3FPR

On 2/28/2012 12:06 PM, kf4ueo wrote:
> I have an early K2 with K2SSB that has been mostly upgraded to Rev B. I don't
> have any issues with my K2 but have always wondered over the years if I need
> to upgrade the filter/BFO/SSB crystals. I have tended to think however "if
> it aint broke..." etc. I have done the flatness SSB mod. Is it worth it?
>
>
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Re: K2 Sn ~700 need upgraded filter crystals?

Guy, K2AV
I did all the A to B and other mods all in the same month, but one at a
time, so I could see what they did.  The crystal swap made quite a
difference in mine.  And changing them out is the only way you'll know if
it helps.  Doesn't help much if you'd like to know whether it's worth it on
YOUR K2 before you do it.  73, Guy.

On Tue, Feb 28, 2012 at 12:21 PM, Don Wilhelm <[hidden email]> wrote:

> Your BFO crystals are OK - there was no change.
> With the older crystals - sometimes they made fine filters, it was
> something like "the luck of the draw" because the motional inductance
> was not specified.
> I would generally recommend you change them, but as you say, if it ain't
> broke, don't fix it.
> In every case where I have changed the crystals for an upgrade customer,
> there has been an improvement.  When you change the crystals on the KSB2
> board, that is a good time to change the capacitors that control the
> filter bandwidth - the caps are easier to change while the crystals are
> removed.
>
> 73,
> Donn W3FPR
>
> On 2/28/2012 12:06 PM, kf4ueo wrote:
> > I have an early K2 with K2SSB that has been mostly upgraded to Rev B. I
> don't
> > have any issues with my K2 but have always wondered over the years if I
> need
> > to upgrade the filter/BFO/SSB crystals. I have tended to think however
> "if
> > it aint broke..." etc. I have done the flatness SSB mod. Is it worth it?
> >
> >
> ______________________________________________________________
> 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
>
______________________________________________________________
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Please help support this email list: http://www.qsl.net/donate.html