Thursday, May 19, 2011

Introducing the Elecraft KX3

Ultraportable Elecraft KX3

Under the tantalising subject line “Something *really* new at Dayton from Elecraft” and while en route to Dayton – Elecraft’s Wayne Burdick N6KR announced to the Elecraft email lists a very interesting new offering to be launched there – the KX3 and a companion 100W amp.
According to Wayne, the KX3 handles all modes, SSB/CW/AM/FM/DATA (the latter including built-in PSK31 and RTTY encode/decode/display).
He promised to post full details and photos later this weekend. But that was too intriguing for the list. This is an edited and probably repetitive summary of what they managed to find out about the new set.
KX3: Ultra-compact K3/KX1 hybrid, 160-6 m, 10/100 W, all-mode, 32-bit DSP/SDR, 1.5 lbs.
  • 1.5 lbs
  • 1.7″ x 3.5″ x 7.4″
  • KX1 form-factor
  • internal battery pack & charger
  • internal wide-range ATU
  • new adjustable, attached keyer paddle
…and a K3-like front panel, including the same LCD.
RX-mode current drain ~150 mA. Very efficient on TX, with dual-output-impedance 5W/10W PA.
The optional 100W amp is in an external chassis. The internal amplifier is 10W with switchable impedance matching so it can also operate with maximum efficiency at 5W.
PA output impedance switch allows efficient 5-W use from internal batteries, or 10 W from external supply.
100 W+ with new high-performance external amp/ATU that works with most 5W to 10W rigs.
>Same flat layout as the KX-1 – just bigger box I would assume????
Yes, but with new fold-up rear tilt-feet.
>…and a K3-like front panel, including the same LCD.
> And it makes use of EVERY display on that LCD?? Carumba!
Not quite. I think there are a couple annunciators that are not used. But it’s amazing that the design team managed to fit almost all the features of a 10W K3 into a box that is a small fraction of the size and weight. And with space left over for an internal battery pack!
By the time we’re done, we’ll be using every icon.
Totally different architecture than the K3, of course. (Wayne N6KR)
RX-mode current drain ~150 mA. Very efficient on TX, with dual-output-impedance 5W/10W PA.
> More $$$ or less $$$ that the regular K3?
Much less.
> Dual output impedance 5w/10w pa? I don’t understand.
The MOSFET 10-W amp stage includes an output transformer with both 1:4 and 1:1 windings. When using low power, or when running from internal batteries, the 1:1 winding is used, which optimizes efficiency at about 5 W, greatly reducing transmit current drain. The 1:4 winding is used when running higher power (using an external supply).
> One email said 10w/100w models. Is that correct?
The 1.5-pound radio itself puts out 10 watts+. We’ll also be describing a new, high-performance 100-watt+ companion amplifier/ATU for fixed-station/mobile use. It will work very well with other 5 to 10-W radios besides the KX3.


  1. As North Atlanta Ham Radio Operators, my wife and I plan on using the KX3 portable, mobile and base. When we are in the car showing residential real estate (we are both hams and real estate brokers who work the North Atlanta Area) the KX3 will be perfect fit for the car. Because there are 2 of us, one can stay in the car when in a QSO, or playing with radio, the other can go in and show home! With Portable, a picnic using a buddipole or buddistick should work great! We have several sets of Nimh batteries, most low discharge, for portable use also! For really portable, we have 90 degree BNC adapters and extendable portable monoband antennas!

  2. Steven thanks for stopping by the blog and taking the time to comment. It's great that you and Tascha are able to combined work and ham radio. I agree the KX3 is the perfect fit for you and the biz that you are in. I use my K2 in the car along with mono band whips and they seem to work great. Once you get your KX3 and have had a chance to use it do email me back to let me know what you think of it.