[Elecraft] K4 Experience

[bruce whitney]

Got my new K4 - just before FD, so naturally hauled it out and ran it all day and night.....It is a real thing of beauty and grace - for sure. A pleasure to operate and many. many, excellent features. Well worth the money and wait.  Gonna take a little while to get to know it well. Its a good thing that the basic control is so similar to the K3.
Here is a bit of information that may be of interest to those thinking about the K4HD.We were operating the K4, CW (BTW - fabulous QSK!) on a 40M ground plane antenna about 150 ft from a station on  40M SSB using an inverted vee antenna.. The SSB station was a K3 (new synth) at 100 watts. S-meters both pegged when tuned to each other - with no damage occurring to either. radio. The K4 (version 13 software delivered in it) was showing a red + sign, indicating A/D overload and was producing some obvious "splatter" from the headset on CW frequencies. By cranking in attenuation we found the splatter would disappear with 9 to 15 dB. There was no other discernable artifact - like pumping of AGC in either case.  We put another  K3 right on top of the K4 - tuned to the CW frequencies, switched the antenna - and no splatter. Then turned off the K3 and operated all day and night with the K4 - what a pleasure. 
So, conclusions... no surprises. The direct sampling SDR is not quite as robust as the superhet. Just as the Sherwood data shows.  I think if we had been able to load the version 18 firmware before field day - we would have never known the SSB station was on the air. I wish we could have tried that.
This is not a rigorous investigation at all. No notes were taken or measurements made. - please  don't beat up the messenger. This is just a single anecdotal experience. IMHO - a multi-multi contest station might want the HD version, maybe? Rest of us - not so sure.
73, Bruce Whitney  W8RA