[Elecraft] K2 version A and B

[Don Wilhelm]

Barry,

I did make one error in my post - it relates to the blue core toroid - 
it is at RFC1, not RFC4 as I indicated.

With the Covid-19 problem in California, I suspect that the website may 
have some uncorrected errors at this time.
I will send a copy of the K2AtoB instructions in an off-list email.

73,
Don W3FPR

On 6/25/2020 4:35 PM, barry halterman wrote:
> Thanks for the reply Don. I tried to down load the instruction manual 
> but get an error "page not found", so wasn't sure what mods were 
> incorporated.
>
> Barry
>
> On Thu, Jun 25, 2020, 3:25 PM Don Wilhelm <donwilh at embarqmail.com 
> <mailto:donwilh at embarqmail.com>> wrote:
>
>     Barry,
>
>     All K2s above SN 3000 are revision B - and that is what is being
>     shipped
>     today.
>
>     The original Field Test and Rev A K2s began to have many mods
>     added to
>     them, so finally the boards were laid out again to incorporate all
>     those
>     mods onto the new boards - the result was Rev B.  I believe that
>     happened in 2003.
>
>     A fully upgraded early K2 will perform just like a brand new one. 
>     One
>     witness to that fact is my SN 00020 which was a Field Test model.
>
>     There are a substantial number of mod kits for the K2, and they are
>     listed on the K2 A to B upgrade instruction sheets.
>     The one thing that is not covered in those instructions is the
>     installation of the upgraded IF crystals (changed at SN 2560) and the
>     KSB2 mods such as the PSK mod and the widening of the KSB2 filter to
>     2.4kHz instead of the original 2.1kHz.
>
>     Also not covered is upgrading the KPA100 - the KPA100UPKT will
>     bring any
>     KPA100 up to the latest level.  The KPA100 does not carry a serial
>     number, so the latest level must be determined by inspection. If
>     toroids L16 and at RFC4 have blue cores, it is the latest. The older
>     ones have red cores at L15 and L16.  There have also been upgrades in
>     the KPA100 shield.  The latest has a 1/4 inch wide slot above the
>     SO239
>     jack and has spring clips that ground the shield to the sides of the
>     base K2.  For other than the Field Test KPA100s, the board has not
>     been
>     changed.
>
>     73,
>     Don W3FPR
>
>     On 6/25/2020 2:51 PM, barry halterman wrote:
>     > Could someone tell me main differences between the version A and
>     B for the
>     > K2?
>     > Is the version B being shipped now if ordered?
>