Elecraft KX3

A compilation of all the information available so far about the latest Elecraft design, the Trail Friendly KX3

Steve G4GXL’s 10 minute YouTube video of Wayne N6KR’s quick overview of the new KX3 is available from http://qrparci.org.

Jeff Davis KE9V has postend photos of the KX3 on Twitpic here.

Benny Aumala’s rendering of the front panel layout is here. It’s based on a photo by Bruce, N1RX.

Details of the new Yahoogroups email list can be found here.

Bruce Before N1RX also posted page one of a descriptive flyer on the KX3 and page two.

(sourced from this information sheet distributed at Dayton – subject to change)

°160-6 meter ham bands; general coverage from 1.6-30 MHz (optional broadcast-band filter module covers 0.5-1.6 KHz)
°All modes: SSB, CW, Data (four sub-modes), AM FM
°Ultra-compact size: 3.4″H x 7.4″W x 1.7″D; 18 oz. (less options)
°Rear tilt feet fold up for transport
°Custom high-contrast LCD with alphanumeric text display
°Current drain as low as 150 mA in receive mode
°High-performance 32-bit floating-point DSP
°Built-in PSK/TTY decode/encode allows data mode operation without a PC; transmit in data modes using CW keyer paddle
°Low-noise synthesizer with 1-Hz tuning resolution
°Firmware updateable via provided application software

°Quadrature down-sampling mixer compatible with PC-based SDR (software-defined-radio) applications
°Receiver I/Q outputs for use with PC soundcard
°Narrow roofing filter option with four bandwidths (500Hz, 1500Hz, 2700Hz,3800Hz) for excellent dynamic range
°Switchable preamp (2 levels) and attenuator (2 levels)
°8-band receive audio equalizer
°Dual watch over ?10kHz range; uses applicable roofing filter
°Easy-to-use PassBand Tuning (PBT) for shift/width/hicut/locut; roofing filters automatically track DSP filter settings
°Automatic and manual notch filtering; adjustable noise reduction and noise blanking; binaural audio effects for enhanced receive
°Center-tuning indicator for CW and data modes
°Built-in speaker; stereo jack for headphones/external speakers

°Adjustable output, 0.1 to 10W+ (100W+ with KXPA100 amp)
°Ruged, SWR and temperature-protected final amplifier stage
°Optional MH3 microphone with PT and UP/DOWN functions
°Optional attached keyer paddle with spacing adjustment
°Switchable PA output impedance for efficient 5-W or 10-W use
°Fast, silent, PIN-diode T-R switching – no relays
°DSP speech processing for excellent “punch”
°8 band equalizer tailors passband to your voice and microphone

°Built in digital voice recorder (DVR) with two message buffers
°Internal CW keyer with 8-50 WPM range
°Six CW/DATA message memories
°100 general-purpose memories store VFO A/B, modes, etc.
°Accessory/RS-232 port for computer control using supplied cable
°Full remote-control command set works with most amateur radio software applications (emulates Elecraft K3)
°One-click firmware upgrades via the web (with free PC software)
°Optional mobile bracket compatible with RAM-mounts
°Tutorial-style manual ideal for new hams

°KXFLE Roofing Filter Module (500/1500/2700/3800 Hz)
°KXAT3 Internal, Wide-Range 20-W Automatic Antenna Tuner
°KXAM3 Broadcast Band Filter Module (0.5-1.6 MHz)
°KXBT3 Internal 8-AA Cell Battery Pack with NiMH Charger (Batteries not supplied; non-rechargeable batteries can also be used)
°KXPD3 Precision Keyer Paddle
°KXMM3 Mobile Mount Bracket
°MH3 Hand Microphone with UP/DN Controls
°KUSB RS232 to USB Adapter
°KXPA100 High-Performance 160-6 meter, 100-W Amplifier; usable with most 5 to 10 W transceivers
°KXAT100 Wide-Range 100-W ATU with Dual Antenna Jacks (attaches to KXPA100 module)

(from Elecraft reflector)

KX3: Ultra-compact K3/KX1 hybrid, 160-6 m, 10/100 W, all-mode, 32-bit DSP/SDR, 1.5 lbs.


  • 1.5 lbs (680g)
  • 1.7″ x 3.5″ x 7.4″ (4.3cm x 8.9cm x 18.8cm)
  • extended KX1 form-factor (KX1 – 1.2 x 3 x 5.3″ (3 x 7.5 x 13 cm) KX1 base weight 9oz / 255g)
  • 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.

KXPA100 – 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.

> 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.