The document discusses the features and performance of the K3 HF Transceiver. It highlights its high performance first IF filters down to 200 Hz, high performance noise blankers, 8 band parametric TX and RX equalizers, and ability to decode PSK and RTTY directly from the CW paddle. It also summarizes the K3's dual diversity receiver design, high resolution color spectrum display, best-in-class blocking and intermodulation dynamic range, excellent DSP AGC impulse rejection, low phase noise, and strong front-end design providing great receiver performance. Real-world testing of the K3 on a DXpedition resulted in new records for number of stations worked simultaneously across multiple bands and modes.

1. Inside the K3 High Performance Rig Design Dynamic Range is your friend! Hands on Ham Radio . © 2009 Elecraft, Inc.

2. The K3 HF Transceiver

3. K3 – What’s New? High performance 1 st IF Filters down to 200 Hz @8.215 MHz IF Shift / Pass Band Tuning High Performance Noise Blankers: H/W and DSP– Both Adjustable 8 Band Parametric TX & RX Equalizers PSK, RTTY, CW Decode. ( Send data modes from CW paddle!) General Coverage RX BPF Option High Performance ATU w/2 ANTs - Matches 10:1 SWR 100% Remote Controllable; Built-in isolated sound card interface K3 MCU & DSP Software Upgrades via the Internet (or local files) Up to 9 Transverter Bands with correct frequency display.

4. K3 – RX performance Hybrid SDR / Analog Design High Q front end band-pass filters Switching Mixer = Better Dynamic Range Low Noise Synthesizer (L.O.) Dual Diversity RX = More signals heard .

5. Fully independent High-Performance RX Independent Synthesizer, NB, filters etc Split off of main RX path or from a 2 nd Antenna 3 modes of operation: Sub RX = VFO B (VFO B = TX if running split) Linked: Sub, VFO B, Tracks VFO A (with or without offset) Dual Diversity: True phase locked RX from two antennas at once. K3 High Performance Sub-Receiver

6. Dual Diversity RX Two identical, phase locked Receivers. Use different antennas (TX ant, beverage etc.) Tune both together with main VFO knob RX1 in left ear, RX2 in right ear. Different signal arrival angles and directions. Fades at different times in each RX = less fills. Pile-ups / QRM spread out spatially. Use your brain to pick out signals by their L-R location. (+3 to 6 dB)

7. High Resolution Color Real-Time Spectrum Display Fast Spectrum and Waterfall Displays (+ Split Screen) Plug and Play with the K3 – No PC S/W Problems! Full Integration with K3 – Panadapter Tracks Main/Sub VFOs, Point and Click Tuning etc. Software Downloadable for future options. Ships by end of this year (2009) P3 DSP Panadapter for the K3

8. P3 - DSP Panadapter for the K3 P3 in Full Spectrum Display Mode

9. P3 - DSP Panadapter for the K3 P3 in Split Waterfall / Spectrum Display Mode

11. De-sensing of RX by off freq. signals Impacted by RX front end design. Impacted by PLL Phase Noise Test Methods: 20, 5, 2 kHz spacing K3 BDR = 140 dB+ Blocking Dynamic Range “De-sense”

12. Inter-modulation between strong multiple off frequency signals produces distortion products inside the receive IF bandwidth. Dynamic Range = IMD Signal Level - MDS K3 IMDDR3 = 104 dB IMD Dynamic Range “Intermod”

13. Dynamic Range

14. Subject: K3 testing Date: Sat, 09 Feb 2008 From: Rob Sherwood <Rob@nc0b.com> Dear Eric and Wayne, The high side and low side IMD is very well behaved, and virtually identical. Good job. 3rd order intermod dynamic range @ spacings: 100 kHz 500/500 filtering: 104 dB 20 kHz 500/500 filtering: 104 dB 5 kHz, 500/500 filtering: 102 dB 2 kHz 200/200 filtering: 101 dB It looks like you are top dog now! Better than the Orion II, the Flex 5000A and certainly better than the IC-7800.

15. DSP AGC impulse rejection = Smooth RX Subject: K3 Date: Sat, 09 Feb 2008 From: Rob Sherwood [email_address] ..the K3 passes the ‘Sherwood AGC test’ with flying colors. 1 V. P-P very fast rise time pulse, 1 PPS, is basically ignored by the AGC I think it is better than all the other rigs that have come out in the last few years which fail miserably: FTDX-9000, FT-2000, Orion II, Omni-VII, IC-7000, IC7800. AGC Performance

16. Phase noise = the off frequency sideband energy of your local oscillator (VFO) in RX and TX. High Phase Noise: Limits Sensitivity and Dynamic Range by mixing off frequency signals on to your IF frequency. Limits Blocking DR. Transmits broadband noise across all of the band. The K3’s Receive and TX Phase noise is -140 dBc at 10 kHz, -150+ dBc at wider spacings. 15-25 dB lower than ‘pure’ SDR transceiver TX and RX phase noise. Phase Noise

17. Strong Front End Design Hi-Performance Switching Mixer, Post Mixer Amp. Narrow Band-pass Front End Filters Low Phase Noise (Low noise LO) Optimal Gain Distribution; AGC Design High Performance Crystal Filters True Dual Diversity RX opens up a new dimension. K3: The Basics = Great RX Performance

18. VP6DX All K3 DXpedition to Ducie Island (Pitcairn) New records for number of stations worked. 2 K3s on all bands simultaneously (CW/SSB)