There was a ham review of one which got removed. What goes?
There are still two reviews here on eham. But they are from N6XI and N6TV. To my knowledge, they are "field test" radios provided and authorized by Elecraft. Not from the supposed recent production shipments of original orders to the hams that put down deposits two years ago. On their website, Elecraft claims to have been shipping for the past one to two months. Strange that we haven't seen any reviews from those batches.
Hope the recent one posted, covered the gap, do not why I had to split it in to parts, apparently was too long, but others are actually much longer?
Anyway, full text below, with links, these could not be inserted in the review section.
K4D field test (
https://drive.google.com/file/d/1zUiZdaxjx6EXzqfNA7YEHy4iE30V8fNw/view?usp=sharing)
A lot has been said already about the recent Sherwood’s lab tests.
Some argued about being even below the K3 on the list, blocking was also a concern, etc.
Aside from the above, for which, given the different architecture, the number is just to pinpoint the value at which IMD3 is starting, without telling what happens from there till the blocking, for which I would suggest Adam’s IFSS test report, my attempt to emulate the K4 behavior (
https://drive.google.com/file/d/1W192h6uLfCu1O1sSGP-n5JhZvFKQu7ak/view?usp=sharing)
The on air test of the K4D #158, was extremely convincing, SSB and CW modes were carried out, a couple of contesters, of which one also took part at the WRTC 2018 were invited at my QTH for a more CW in depth.
Once you turn the radio on (about 20 sec. to boot), the impression is of a “deaf” receiver, the base band noise sounds very low on the headphones, whereas, when you tune on even a weak signal, this, beside being extremely clear and clean, comes out very loud at the point that you are somehow disappointed when looking at the S meter, thinking it might be an S9, instead is only an S5 or less, the audio recovery, is definitely superior to what I am experiencing on my knobless DS on a daily basis.
On the higher bands, the use of pre-amps (up to 3 on 6/10 and 12m) do not change the feeling, given the excellent audio recovery, I found myself not tempted to turn them on, except on 10m and 15m, where given the MDS (500Hz) at 121dBm (this radio does not have an ADC driver always ON as per the 7610 or the ANAN 7000DLE, probably the only architecture difference among the three) and my rural background noise at -125dBm, the pre1 12dB of gain becomes necessary to have some spare dB of sensitivity from with or without antenna.
The radio was setup at a very basic level, no logging interfacing or else, just an external monitor via an HDMI VGA adapter, a USB wireless mouse plugged in the front USB port, a Yamaha CM500 hooked into the rear 3,5mm plugs was initially attempted, as I could not make it to sound properly (hollow sound), I switched to an old Heil headset using the HC5 cartridge, this suited the radio perfectly from the beginning, just tweak the EQ to my liking.
Several contacts were made on 20 and 40m with good audio reports, the use of the radio was pretty straight forward, even for a knobless operator, the three multi function knobs to the left, along with their aside displayed values allows a very easy access to them, as a side note, being a radio clearly designed to meet the most demanding operators, I would have gave up the main/sub sql control in favor of the AGC threshold, quite meaningful on DS radios.
The digital BW filter works as expected, continuous adj, without loosing intelligibility even at very narrow setting (<2kHz)
A Bencher paddle was used on CW, QSK worked flawless, minimum BW 50Hz, APF at 30 and 50Hz, the CW guy, was having the same impression I had on SSB, given the contest ongoing he went even further telling about the distinct separation among the many signals on the band, no sign of clicks while slightly tuning off of loud signals, easy to pick up multiple stations calling as long as they were not perfectly zero beat, click and tune by means of the mouse and pleased to easily find a clear spot, even from the on board monitor.
Now the DS Achilles heel, blocking DR, for which Elecraft has a foreseen HD model, radio was put on 40m at sunset, 2L beaming East, at that time in Europe the band from 7.200 and above is full of very loud Asian BC, mostly Chinese at +40/50dB over S9, the attempt was to overload the radio, we went as far as turning ON even the pre2, as we could not make it happen, with the latter ON, for a brief amount of time, I could finally see the magenta + sign turning ON, but the radio was still operating normally, sign of a light temporary OVF. (
https://drive.google.com/file/d/10CbwP20vSlZinWxY2YjeersoQZgG6YNs/view?usp=sharing)
More considerations were made and few notes were taken to eventually address to the manufacturer, aside from the predisposed hardware functions as pre-distortion (coupler & connector) for which a SW might be implemented on a later stage, or diversity which does not have a SW behind it for beamforming/null steering, thus works in stereo mode only, the rec&play function is textually “implementation in progress” along with the messages bank.
The above are objective findings based on the on air operations, as a personal note, being a long time direct sampling user, the choice of not always having a driver in front of the ADC, looks like the winning one, as, even on a quiet rural place, preamp1 is deem necessary only from 15m up, while on mid or low bands, -121 dBm of MDS is more than plenty, making the
radio sounding more pleasant and robust.
73, Clay I4LEC