[Elecraft] K3 vs KX3

[Wayne Burdick]

Jim Brown <jim at audiosystemsgroup.com> wrote:

> What do you lose ([with a KX3] as compared to a K3)?  1) TX phase noise that's in the range of the best of the other radios in the same price category, so you wouldn't want to contest with it driving a big power amp (just as I'm pretty unhappy with an IC-7600 10 miles away doing that); 2) It's less accommodating to interfacing stuff like computer sound cards; 3) You need outboard stuff for a spectrum display; 4) Less audio output -- if you want to listen on speakers, you need something external that's amplified.


The K3 is really a completely different animal:

- It is intended as a base station radio, with twice as many controls and a built-in 100-W amp and ATU. 

- It has a fully independent sub receiver with the same specs as the main. The sub can be on a different band, and has no limit on VFO separation within bands like the KX3's dual watch. 

- It has up to 5 crystal filters per receiver, and if you outfit it with narrow filters, it will have better dynamic range than the KX3 for offsets below 2 kHz. The KX3 may have a slight edge in 2-kHz IMDDR3 with its own roofing filter module installed, as listed by Sherwood. But this difference would be insignificant for most uses, and with narrow crystal filters, the K3 will outperform the KX3 in heavy CW and narrow RTTY band conditions. Both are excellent, but if your goal is absolute dominance of the CW/RTTY bands, you'd go with the K3.

The KX3, on the other hand, would be a great choice if you're on a smaller budget and/or plan to do a lot of field outings at QRP levels. It's by far the world's smallest high-performance all-band/all-mode transceiver.

73,
Wayne
N6KR