Friday, May 25, 2018

Elecraft's K2 in a KX2's world

With next week's temperatures predicted to be 100+ (40's C) for several days, and summer only beginning, I've been trying to justify the purchase and build of an Elecraft K2 that will keep me indoors in my near-fanatical appreciation of the magic of freon.

The problem is, I already have a KX2; therefore, the justification requires a careful comparison. Both rigs have so many of the same functions that are important to me: dual VFO's, configurable AGC settings, built-in keyer, CW memories, etc.

Unfortunately, only a general comparison is possible when basing it on the reviews in QST. This is due to the fact that the ARRL reviews for each transceiver are 17 years apart and during that time, some of the characteristics that are measured and how they're measured, has changed.

For the K2, most receiver tests are performed with a bandwidth of 700 Hz; for the KX2, they're performed at a bandwidth of 500 Hz. And an identical series of tests are not performed on each transceiver.

Sherwood's consistency makes it a bit easier to make an apples-to-apples comparison even though the two rigs were tested by him 13 years apart.

Footnotes: b - pre-amp on; f - measurement was noise limited

The price of each rig, similarly outfitted, is $1243 for the K2 and $790 for the KX2. This is with the base K2 ($863 with noise blanker) configured for SSB ($180) and the audio filter ($100) to roughly correspond with the KX2's APF function, and the 60m K60XV ($100). Unavailable on the K2 is general coverage receive and RTTY/PSK operation.

Going through the price vs. features comparison, I realize that it makes me appreciate the KX2 all the more. In fact, it does the opposite of what I'm trying to do in justifying the purchase of a K2.

As I go through this info and engage in the process of consolidating it here, I realize (again) that I wish I'd bought a K2 "back in the day". But back then, the price of a K2 and my own financial priorities prevented me from doing so.

So, receiver specs and dollars aside, the one reason - the only reason - to buy a K2 today is for the pleasure of the build, and that is certainly a worthwhile reason. It'll cost a $500 premium for the pleasure and will result in a rig inferior to the KX2 in almost every way. But there are no other transceiver kits available (and probably never will be) that result in the performance of the K2.

There is something - even after building so many kits over the decades - that is greatly satisfying about having an operational piece of equipment that performs well, and knowing that you put in every single component, would every coil and performed every alignment involved in its "bags-of-parts to radio" transformation.

But I'll keep my $ for other (and future) products.


  1. Funny you post this, John, as I'm planning to put my K2/100 up for sale this weekend at a hamfest. I wasn't the original builder--I purchased this unit from a local SK sale.

    Why am I selling it?

    Well, I own both the KX3 and KX2 and completely agree with your assessment above. (Although I also agree that it's worth a premium to build a radio like the K2!) Also, the K2 lacks a gen coverage receiver--something I've grown to love in a modern transceiver.

    Since owning the KX3, I have rarely put the K2 on the air. The KX3 is so much easier to use, and so versatile.

    The two reasons I've kept the K2 is because it's designed to repair and modify (even through hole!), and it's a 100W rig (a better field day option, perhaps).

    Since owning the KX2, I pretty much use the KX3 as a home rig and the KX2 as my portable.

    When I sell the K2/100, proceeds will fund the KXPA100 amplifier. A true chunk of change, but I think it'll be worth it. feels funny selling the K2/100. It's still a brilliant rig and outperforms so many others on the market. A truly groundbreaking design that's held its own.


    1. Hi Thomas,

      I've thought about the KXPA100 too but new things keep calling. I'm particularly interested in all the new SDR radios coming to market - not just transceivers but receivers too. The RSPduo has taken up far more of my time lately than I would have thought possible for a non-transmitting radio - mainly because it's also a piece of test equipment.

      I look forward to reading of your experience with the KXPA100 if you get one. There is a time for QRP and a time to exceed those limits. I operated CQ-WPX this weekend with the KX2 and KPA500. It's nice to have the KX2 operating as if it were a QRO rig and I like that combo much better than my FT-891.

      73 for now,
      John AE5X

  2. I too have a K2 and KX3. The K2 (10W, 160m, SSB, DSP audio, RS232 and ATU) was built by me back in 2001 and for a time was my only radio. It was a very satisfying build and has had a lot of use.

    The most recent use was in Spain as a holiday rig, where it was left between trips. While it worked well enough, despite having all the mods, it does drift a little and is awkward to align to better than 100 Hz accuracy. For the most part it doesn't matter about "spot on" accuracy.

    A friend was looking to replace his KX3 with a KX2 for his SOTA work and sold me his KX3. It is so much better than a K2, especially when you run the extended temperature cal on the KX3 (very easy, there is an Elecraft paper on how to run the cal). Other than the building experience, there is no advantage in the K2 vs a KX3 and that probably goes for the K2 vs KX2 as well. My K2 gathers dust and the KX3 goes with me to Spain.

    73 Dave G4AON