[Elecraft] Building an older K2

Don Wilhelm donwilh at embarqmail.com
Sat Dec 23 18:21:08 EST 2017


Joe,

Thank you for passing along the serial number - that helps a lot with 
the K2 level.

Any K2 above SN 3000 is up to date with all upgrades (including the IF 
crystals) - with one exception, the K2 Keying Waveshape Mod which was 
introduced at SN 4660.  That mod kit is no longer available as a package 
from Elecraft, but I can send you the instructions and parts to order 
(send private email).  That mod is important for eliminating keyclicks 
that become obvious when an amplifier (such as the KPA100) is added to 
the K2.

If the KSB2 kit is included, you may want to order the SSBCAPKT to 
increase the OP1 filter bandwidth to the current 2.4kHz.

Check the firmware level, you may want to upgrade it to the current 
2.04r level - order FWK2MCIO from Elecraft.

For the KPA100, order the KPA100UPKT and KPA100SHLDKT.
The KAT100 has had no changes since day 1.

If you do all that, you will end up with a K2 that is current with those 
being shipped today.

Work carefully, and if you are unsure of what a good solder connection 
looks like, download the Soldering Tutorial from the Elecraft website. 
Most builders mistakes are from faulty solder connections and improperly 
stripped and tinned toroid leads.

Follow the instructions as written - they are correct.  If you do not 
understand a step, ask here and you will likely get an answer.

You may want to download the current manual (and errata sheets) and 
build from that.  For the base K2, the manual you have is similar, but 
some things have changed.

If you order the KPA100UPKT, definitely build from the latest KPA100 
manual (you will have some parts left over).

When winding toroids, be aware that a straight wire through the center 
of the core is 1 turn - a full wrap around the core is two turns.
If you are not up to winding your own toroids, you can order the 
pre-wound toroids from "The Toroid Guy".

73,
Don W3FPR

On 12/23/2017 5:09 PM, Joe Harris wrote:
> Hello all,
> 
> It's been years since I did any serious kit building, and I've been looking
> for a good winter project for a while now. So, when I found an unbuilt K2,
> KPA100, and KAT100-1 as part of an estate sale, I jumped on it.
> 
> Are there any potential pitfalls I should be aware of, or is there anything
> I should be concerned about when assembling a 15-year old kit? All the
> boxes have 2002 purchase dates noted on them. The K2 is SN 3172, so I know
> it has the Rev "B" RF board.


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