Hello Guy, Ian, Don, Eric, Ed…... Very enlightening posts, thank you!
As a ham who has only, in the last 12 months, returned on air after 30 years, this information is very relevant. So on your advice I did some more testing and can confirm that using WinK3Suite remotely via the RemoteRig K3-Twin system works perfectly for CW/RTTY/PSK. No need to use Fldigi/sound card or USB for those modes….nice and clean. For JT65/JT9, which cannot be provided “in the box”, I am forced to use the sound card tones at the control end of the remote link (which the RemoteRig appliances send to the remote K3S via the MIC IN). Elecraft Support insist that I should use DATA-A and keep a close eye on the ALC so as not to cause any spectrum problems. Ed, thanks for doing the tests. I assume WSJT-X is the same as WSJT10, so I think I’m all good. I must say that I am having a ball on these new digital modes and enjoying DX’ing much more than I ever did 30 years ago. The ability to work an Iraq station on JT65 at -20dB who was running 30W into a dipole is extraordinary, particularly from this part of the world in a declining sunspot cycle. Best 73, Graham VK3GA > On 23 Sep 2016, at 6:21 AM, Guy Olinger K2AV <k2av....@gmail.com> wrote: > > [In the following text, "both the K3 and the K3S" is represented by "K3/S". > Text applicable to only one or the other will be "K3" or "K3S"] > > Hi Graham. > > With a warm smile, a soft voice, and friendly demeanor. I have had to go > through this post-analog era "de-analoging" my own radio perceptions, and > have had a fairly painful time of it :>) > > The big lesson from my de-analoging was just how much my traditional analog > thinking, ground in by 50 years of analog hamming experience on analog > equipment, was keeping me from moving on. I needed to understand, cope with > and take advantage of very superior digital methods in a new digital era. I > was really pretty clunky. That said, not reporting any genius-level learning > rate on my part to claim superiority... > > There is no suppressed carrier in software derived radio (SDR). In the K3/S > the single sideband envelope is generated directly from firmware. It begins > with data from analog to digital converter chips (ADC) on line in or mic > leads. Firmware converts this to SSB representative data, sent to a digital > to analog chip (DAC) directly outputting SSB at the 15 kHz TX IF. There is no > carrier to null or filter out. There is no opposite sideband to phase out or > filter out. There are DAC and frequency conversion artifacts which need to be > removed by one means or another (as in going through a 2.7 kHz wide 8 MHz > crystal filter also used for receive). > > CW is not a keyed carrier any more. It is directly generated by the DAC chip > to the 15 kHz TX IF from digital data representing an ideal waveform. The > normal keying "sidebands" of the CW signal are also from that data. The > frequency conversion, and linear amplifier stages following, will add some > additional sidebands based on their degree of linearity, hopefully very well > down. > > For frequency display, in CW mode the K3/S will display the single frequency > of the central signal. > > For SSB and any mode generated through DATA A, the K3/S will display the > traditional amateur radio SSB frequency, which is what you would get if you > could somehow create SSB output from a DC voltage applied to the K3/S > transmitter line in or mic inputs. Note that some other radio services use > center of bandwidth as the frequency for SSB operation. > > Use of audio input for keying should be avoided where possible. Note that you > can generate CW, FSK, and PSK without use of audio input, producing ideal > keying and bandwidth. Signals generated this way are without any audio input > artifacts like 60, 120, 180 Hz hum, audio harmonics from low level > distortion, audio noise or hiss, or miscellaneous unwanted audio from > grounding issues, or feedback from mild RF in the shack, or miscellaneous > audio from other apps on the PC bleeding through PC "soundboards". > > The state of digital direct signal generation for CW is so clean that it is > simply poor amateur practice to generate CW from audio tones. There are so > many ways to screw up CW in the audio. The reputation of very clean CW from > K3/S depends on the direct data generation of CW in the K3/S > > The key jack input on the back of the K3/S is itself converted to data on one > lead of an ADC chip, and sent to the CPU as data, only one data "channel" on > a single multiplexed data line, informing the CPU that the key is *reported* > high or low. That key jack voltage is not used directly for anything except > to be sampled, and advise the CPU whether the jack is keyed or not. The CPU > directs other stuff based upon the *report* of keyed or not. It can do > exactly the same thing from a string of characters converted in firmware to > the *effect* of *reports* of keyed or not. Ditto FSK D and PSK D. > > In a contest, I would not want to be the next station up or down frequency > from you doing audio generation of CW. I urge you to permanently discontinue > that practice. > > I would also urge that you use FSK D and PSK D where possible to transmit > instead of audio tones. These are all successfully employed by some remote > users, though I can't speak to the methods or their complexity. > > FSK D and PSK D will occupy minimum bandwidth by virtue of ideal waveforms > and be independent of all the audio train issues of gain, noise, level-based > distortion and AC power artifacts between user PC generation, audio train, > and the K3/S. > > Use of the K3/S USB "soundcard" in some setups does remove some audio > transmission issues, but you are exporting the "quality control" of waveforms > to the third-party program running on the PC. Third-party programmers are not > going to take responsibility for K3/S output waveshape. > > Sorry to rag on, but not excessively sorry. :>) > > 73 and good luck with all the remote stuff. > > Guy K2AV > > On Thu, Sep 22, 2016 at 1:37 AM, Graham Alston <gra...@alston.com.au > <mailto:gra...@alston.com.au>> wrote: > Hi, > > I’m very new to Elecraft and K3S so hope this is not too obvious…. > > I have a K3S connected to my PC with audio tones coming in via MIC IN (in > reality the K3S is the remote end of a K3-Twin remote setup). > > When I use DATA-A sub mode for CW, the transmission is 600Hz higher than the > VFO frequency. I assume this is because DATA-A transmits on the USB and the > VFO shows the suppressed carrier frequency? > > I want my CW signal to match the VFO, how can I do that? > > 73, Graham VK3GA > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > <http://mailman.qth.net/mailman/listinfo/elecraft> > Help: http://mailman.qth.net/mmfaq.htm <http://mailman.qth.net/mmfaq.htm> > Post: mailto:Elecraft@mailman.qth.net <mailto:Elecraft@mailman.qth.net> > > This list hosted by: http://www.qsl.net <http://www.qsl.net/> > Please help support this email list: http://www.qsl.net/donate.html > <http://www.qsl.net/donate.html> > Message delivered to k2av....@gmail.com <mailto:k2av....@gmail.com> ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
