[Elecraft] K2 Sn ~700 need upgraded filter crystals?

[Don Wilhelm]

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?
>
>