Here are personal opinions on the Elecraft K4 from the perspective of a moderately active ham and a K3 user since 2007. As an “In-House” field tester, I’ve had a K4 on the air for three years now, but it is only in the past few months that I’ve really given it a workout. Since autumn, my K4 has worked several thousand stations in each of the big modes: CW, SSB, RTTY, and FT8.
First impressions are lasting, and those from the very first operating session in 2020 remain impressive: its big beautiful display, fantastic receiver audio, and unexpectedly low receive background noise. Several other features and benefits of the K4 are now appreciated. Let’s start by getting the rig on the air. Operating CW and SSB are as simple and competent as expected—a “plug and play” experience. It is the “digital” modes such as Baudot RTTY and FT4 & 8 where configuring a transceiver is often obtuse. Not so with the K4. The internal USB sound card and (multiple) USB serial ports reduce the connecting cables down to a single, standard (included) USB cable, making interfacing with a logging computer trivially simple. This single cable handles rig control, CW keying, and sound card in & out for both voice and digital modes. Setting the multitude of interface parameters is accomplished right from the K4’s touch screen.
Operating CW contests with the K4 is enjoyable. While pileups aren’t very big when operating from California, the ones we do get are more easily handled with the K4 than with the very-competent K3/K3S. The combination of excellent selectivity and receive audio, along with enhanced situational awareness from the panadapter make maintaining a decent QSO rate easier.
Ever since the 1980s when I added an SM-220 + panadapter to my TS-940, a band scope has been an operating requirement. The K4’s large panadapter really helps understanding band conditions and is hugely more capable than the technology from “deep in the last century”. Connecting an off-the-shelf computer monitor as an even larger external panadapter display is a great bonus.
Like adding the visual display of the bands via a panadapter, diversity receive mode is something that once experienced, you cannot live without. The K4D has easy-to-use diversity with an excellent selection of five receive antennas. Selecting the correct receive antenna is easy since the K4 displays a user-programmed descriptive antenna label on the screen. With the K3, I was no fan of receive Noise Reduction: my chosen NR setting was “Off”. The K4’s implementation has changed that, as its Noise Reduction is effective without creating annoying and distracting digital artifacts.
My favorite K3 accessories, the KPA500 and KPA1500 amplifiers, and the K-Pod work perfectly with the K4. The K4 sure looks great sitting alongside the identically sized KPA1500 RF deck.
Ethernet connectivity makes the numerous firmware updates offered to a new Elecraft radio almost effortless. It also means that more modern radio control—such as the new Ethernet radio interfacing added to N1MM+ logging software—and eventual remote connectivity is assured.
After losing my custom-built shack to a house fire three years ago, the comfortable size and lightweight characteristics of the K4 is something newly appreciated. It fits in my tiny temporary shed/shack and is easily carried back and forth to more secure locations.
Between the time the above was written and “press time,” I was honored to accompany AD6E/KH6TU to the World Radiosport Team Championships in Italy.
Alan and I each brought our K4s and survived the heat and insects, operating as I44Z from an outbuilding of a rural bed and breakfast.
The K4s never complained once about the heat, humidity, or mosquitos of our assigned location, which had soaked beneath a meter of water during the regional flooding in May. Their fans increased speed only a little bit under the heat generated by our heavy-duty-cycle CQing. We both ran 100 watts on both CW and SSB for a solid 24 hours.
The K4 panadapter quickly showed us that 10m was disappointing and kept us from squandering much precious time there. On other bands, it directed us to open frequencies amid the QRM. The improved QSK keying eliminated doubling with late callers, again reducing lost time. The ATU matched our low dipole across the 80m band without issue. And of course, the speech processing made our 100W SSB signal sound as if we were running much more power. Both of us also brought KPods which allowed keeping our hands close to the keyboard, further increasing efficiency.
I brought extra monitors: a small flat panel that sat atop the K4 and duplicated the laptop's logging program screen, and a larger one that connected to the K4 video output, enlarging the panadapter. Alan was content with the K4's panadapter screen size and his laptop screen, and thus was able to “stretch out” more on the limited tabletop space we were allocated.
Custom-built hardware (thank you KW6S!) took data from the K4 ACC connector and automatically selected the best antenna while also ensuring that our two stations were never on the same band. We were able to share the tribander (on different bands) and the 40m dipole (on 40m or 15m) as the need arose.
Our 4259 low-power QSOs didn't produce a winning score, but our K4s finished comfortably in the top half of the densely populated pack of world-class operators.
Bob was first licensed deep in the last century at age 12 as WN6HPF, then assigned the callsigns WA6HPF and N6IP, with K6XX received in 1996. K6XX is active on most HF bands and modes, focusing on contest operations. He competed in WRTC-2010, WRTC-2018, and WRTC-2022 and was on the Organizing Committee for WRTC-96. He was elected to the CQ-Contest Hall of Fame in 2021.
Bob has been with Elecraft since 2000 and is presently an Engineering Project Manager and a key contributor to the development of Elecraft's amplifier product line.