Making the K2 portable……..

KAT100 in new enclosure
In a previous post I debated to either jump on the Elecraft KX3 band wagon or convert my Elecraft K2 so it can be used both as a home base radio and also for portable op's. The bottom line for now is the KX3 is out and I am in the process of converting my K2.  The end result will be that I'll have my K2 for portable operations with an internal battery and internal QRP antenna tuner. At home the radio will then hook up to the external antenna tuner (KAT100) and if and when needed the 100 watt amp (KPA100). So I ordered the KAT100, KIO2 (RS 232 interface), KAT2, KBT2 (internal battery) and the
enclosure to house both the KAT100 and KPA100. I have completed the external antenna tuner. It went very smooth
Toroid lineup
Bifilar winding
there were 10 toroids to wind but with practice these are not a big deal. But if you feel this is the only area of kit building that stops you from ordering....there is help!!! The Toroid guy is there to lend a helping hand, you can purchase quality pre-wound toroids for any Elecraft kit. This portion of the project took me about 2 weeks. That is 2 leisurely weeks I try not to do marathon kit building sessions, I end up making mistakes and missing things. The external ATU is now mounted in it's housing (I still have the alignment of the ATU to do). I have removed the KPA100 from the top of the K2 which went very smooth. There are only 3 connectors that plug the ATU into the KPA100 and it's ready to go. It's now time to get the RS-232 inter connecting cables made along with the RS-232 interface that is installed in the K2 built as well. This allows the K2 to communicate with the ATU, Amp and computer. The battery and KAT2 antenna tuner are on there way from Elecraft and I hope when done this next part of the project they will have arrived.
 Above KAP100 waiting to be installed
below from panel assembly

If you are ever thinking of doing this project with your K2 below are some links that helped me out.

KK7P offers some very good advice along with some excellent pictures as well.
Wilcox Engineering also have some nice pictures of the unit and advice.
Mike Weir, VE9KK, is a regular contributor to and writes from New Brunswick, Canada. Contact him at [email protected].

4 Responses to “Making the K2 portable……..”

  • Byron N6NUL:

    Despite my desire for a KX3, I am forging ahead with my own first K2 build and will also put the KAT100/KPA100 option in a second chassis. I am very much looking forward to having my shack be completely hand-made.

  • Yes Byron it is a very nice feeling to have built the rig. I also built the KX1 as well aiong with other accessories for my station. Good luck with the K2 built take your time and enjoy the exspirance.

  • k7zov:

    Great article. Something I have been planning on doing for the past year with maybe a couple variations. But close to the same. My K2 is loaded also, with the battery, SIO, and ATU in the cover and the SSB, NB, DSP, 160/RX in the frame. It is always ready to go and hears better then my 756PROII and IC-7200. Hears better as on a A/B switch the K2 can pull signal out that neither radio even hears at a fraction of the cost or size. But I do have to change the cover for 100 watts for the K2 so having the KPA100 with ATU and maybe more is a real plus. I also have a KX1 and it is also a jaw dropper in performance. So much radio is such a tiny package. So when I look at the KX3 or the coming soon TenTec renamed 599 with the main box being QRP and like the KX3 a separate 100 watt add on I kind of wonder why am I looking. I already have more radio then most people and performance that will be like slipping hairs when compared with what is coming out. So for now I will proceed with making an external KPA100 box and enjoy what I have. At 63 and loosing everything back in 2003 and starting over I really need to keep my eye on my limited income and I really an having fun with what I have. Thanks you for the article. I will have to move that project up on my to do list once we have the white stuff on the ground in a few short weeks.

    Harry K7ZOV

  • Good morning Harry, yes it’s great the K2 can be split up for both home and portable use. I have not had the oppertunity to compare my K2 or K3 to other rigs but I am very happy with both. Good luck with the KPA100 and KAT100 combo. If you have any questions do drop me a line and thanks again for stopping by the blog.

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