The band rebounded nicely after the approach to storm conditions Sunday morning apparently fizzled out. QRN was very low once again although the lightning map suggests that stations in the southeastern US may have experienced elevated noise overnight due to a cluster of storms in the Atlantic. The trans-Atlantic path between North America and Europe improved on the gains from the previous session and the trans-Pacific path between North America and Oceania has been better than the previous night. Lightning persists in the Sea of Tasman along the eastern coast of Australia and western coast of New Zealand so it may be that signal as “just that strong” overnight to be heard.
Geomagnetic activity continues to abate as additional unsettled reporting periods have not been observed. The Kp remains at “elevated quiet” levels so there is certainly a chance for additional storm conditions. The Bz is pointing to the North as it has been for much of session which is shielding us from much of the high speed solar wind that is currently reported in excess of 600 km/s. The trend is that the velocities continues to decrease with each reporting period. DST values remain negative but are generally stable.
Trans-Atlantic openings continue to show promise during this session as G8HUH was reported by WA3TTS (report detail) and VE1HF (report detail). WD2XSH/17 reported PA0A as well as G8HUH and those report details can be viewed here. Ken, K5DNL / WG2XXM, who was heard by 59 unique stations, was reported by F59706 once again and that report can be viewed here. John, WA3ETD / WG2XKA, was the only other North American station to be reported in Europe and he hit it big with decodes from G0LUJ/1, G3XKR, G8HUH, and PA0RDT. Those report details can be viewed here.
Something that I have found to be interesting is that both WD2XSH/17 and WG2XKA are capable of hearing and being heard in Europe on good propagation nights yet there was a lack of reciprocity in the reports during this session. Its possible that John experienced local QRN that prevented him from hearing European stations but the path appears to have been very open so I’m surprised that a station like G8HUH, that was heard by others in the Northeast, was not heard in Vermont. Similarly WD2XSH/17 has been transmitting recently and has received reports from stations in Europe yet he did not have reports from Europe during this session. This behavior could lead back to what I have mentioned before about high station density masking weaker DX signals. Perhaps WG2XKA was lucky enough to find a clear operating frequency while WD2XSH/17 was not. Trans-Atlantic openings may occur more often than we realize.
John, WA3ETD / WG2XKA, adds:
“Very strong conditions to report following the event. All areas of the USA were well represented, including the PNW and far west coast. XKA was spotted by WH2XCR as well as by PA0RDT, G3XKR, and G8HUH, G0LUJ/1. All good!”
Mike, WA3TTS, reports, “Both T/A and T/P captures overnight. First time in awhile…” He provided the following statistics and comments:
“2 G8HUH captures early in the evening. Surprising as my background noise was S4 minimum at the time and peaking to S8.
Note the 0616 UTC capture was made under strong signal conditions. 36 dB difference between XCR and XKA only 29Hz apart…deep search really works!
73, Mike wa3tts”
Mike added the following comments regarding the lack of reciprocity on trans-Atlantic paths for selected stations observed during this session that I considered earlier:
“…I would assume take-off angle (determining distance per ionospheric reflection) and having the shifting block of ionospheric Swiss Cheese in the right place has something to do with it. Past few weeks NE has been noisy. I tried varying the termination resistance on the NE EWE last night and although I was able to get an additional 10 dB of null on XXM, changing the null pattern on the EWE with a variable termination did not seem to help enough to garner additional G8HUH captures. I did see a few additional WSPR2 traces occurring in 2 minute sequences where G8HUH was transmitting up through about 0400 UTC , but I was not able to decode them….Strong XKA captures in the +7 to +12 range are often associated with T/A occurrences here, so in part it must be having an efficient ionospheric reflection from the last water bounce on the T/A path to the inland destination. Mike tts”
Neil, W0YSE/7 / WG2XSV, reports that he heard nine WSPR stations, including VA7MM, VE7CNF, WE2XPQ, WG2XIQ, WG2XXM, WH2XCR, WH2XGP, WH2XXP, and WI2XJQ. He was heard by 25 unique stations, including K6LG, KK6EEW, KO6KL (new I think), N3IZN/RX, N6RY, N6SKM, NB9E, NO1D, SWL/K9, VA7JX, VA7MM, VE6JY, VE6ZC, VE7CNF, VE7KPB, VE7SL, W0AY, W7IUV, WA3TTS, WA6OURKIWI, WG2XIQ, WH2XCR, WH2XGP, WI2XJQ, and WW6D.
Rick, W7RNB / WI2XJQ, received reports from thirty unique stations in addition to providing report to five WSPR stations. Rick’s unique report details can be viewed here.
Ward, K7PO / WH2XXP, received reports from VK4YB and VK2XGJ. Those trans-Pacific reports can be viewed here.
Roger, VK4YB, received reports from VE7SL, JA1PKG, JA1PKG/R, JA3TVF, and ZL2BCG. Those report details can be viewed here.
John, VK2XGJ, reports that in spite of the storms in the sea of Tasman, he has decoded WH2XCR and WH2XXP a couple of times. John also added that Rick, VK6XT, is, in fact, transmitting now and is the first VK6 to transmit on 630-meter WSPR. John reports that Rick has more details on his QRZ page (I would include some of those details here but the site appears down at the moment).
The band showed real promise overnight with good openings into the Midwest all night long. Stations in New England showed promise as WG2XKA was decoded here multiple times during the evening and overnight at levels not observed since last season. I believe that the band was at least as good as it was in the previous session and probably a little better as the geomagnetic field has found some stability. My CW sessions were nominal. Quiet band conditions could have resulted in any number of QSO’s. My WSPR transmission reports can be viewed here and my WSPR reception reports can be found here.
Regional and continental WSPR breakdowns follow:
VP9GE has returned to listening on 630-meter WSPR but no reports were registered at his station during this session.
Eden, ZF1EJ, operated two receivers and two antennas during this session. He reports that ZF1EJ was configured with the Pixie loop directed at 335 degrees while ZF1EJ/1 was configured for the log periodic array so that provides some explanation for some of the observations from last week’s sessions. Eden decoded WH2XCR at ZF1EJ/1 and those report details can be viewed here.
Laurence, KL7L / WE2XPQ, experienced a respectable session with reports at WG2XXM and two-way reports at WH2XCR. Those report details can be viewed here.
Merv, K9FD/KH6 / WH2XCR, enjoyed another strong session with reports at ZF1EJ/1 and WA3TTS and hearing WG2XKA in Vermont. The path to Asia was also good with reports from 7L1RLL4, JA1NQI-2, PA1PKG, and JE1JDL. In Oceania, Merv was decoded by VK2XGJ and shared two-way reports with VK4YB. Those VK and JA report details can be viewed here.
Jim, W5EST, presents, “GENERALIZED LF/MF STATION BLOCKS & CONTROL”:
“The Nov. 8-11 blogs this last week featured T/R and QSY in station control, and considered the limits of 630m QSK. Also, we know MF/LF station control is diversely station-specific for now and probably will continue that way.
Today’s illustration attempts to block diagram the high-level features of LF/MF stations generally, with central emphasis on station control. You may see station designs that depart from this block diagram by omitting one or more blocks or functions. But I think you’d agree that most LF/MF stations mainly differ on several dimensions inside the blocks: 1) their physical layout spread into or between the shack and outdoors, 2) the electromechanical or electronic way they accomplish their functions, 3) separateness or integration of various station elements, and 4) degree of manual control by operator versus automatic or computerized control.
Starting with the transmit chain, today’s block diagram includes some means of developing LF/MF transmit drive whether directly or by some pre-existing equipment augmented with a frequency converter. Next comes a TX power amplifier, because LF/MF transmit antenna systems* are generally electrically short inefficient radiators that suffer a characteristically high percentage of ohmic losses in the grounding system plus some losses in the antenna tuning unit ATU and antenna itself. LF/MF top-hatted TX single verticals predominate, such as Marconi-T and inverted-L – while vertical arrays, end-fire TX antennas and large TX loops provide further interesting radiative players.
Between the TX power amplifier and the antenna system is situated a complex of shack based and outdoor circuits that I lump together as “Post-TX.” These include the ATU, some means of detuning the TX antenna to promote effective reception, circuitry for detecting the state of matching of the TX power amplifier to the ATU, protective circuitry such as SWR trip, manual or automatic tuning/QSY control, and band switching between 630m and 2200m, if any. Post-TX also includes lightning protection,** even as simple as a manually connected base-mounted shorting bar to ground to contribute to station protection before and during a thunderstorm.
Turning now to the receiving signal chain, we see some kind of receive antenna which might be associated with an always-on grabber RX at considerable distance from TX but generally is not. Generally, folks locate their LF/MF receive antenna(s) in the near field – within one third wavelength from the TX antenna. That means that some not insignificant fraction of the TX antenna power is capacitively coupled between the antennas as illustrated, or inductively coupled (blue arrows), or both. Bidirectional or unidirectional RX magnetic loops are frequently used, thanks to their pattern nulls. Also, BOGs (Beverage on Ground), E-probes, and single or arrayed short verticals show up at stations here and there.
To handle or prevent unhappy TX-to-RX power coupling, a Pre-RX section of the station detunes and isolates the receive antenna on transmit, and then on receive efficiently couples or tunes the RX antenna and activates a preamplifier if a preamp is used. Like the Post-TX section of the station, the Pre-RX section may be concentrated indoors or outdoors or distributed between indoors and outdoors. Stations may run separate control lines, or deliver combined RF and control voltages on coax instead, or do wireless controls. Pre-RX noise canceling and control may be included in the system.
The Pre-RX section supplies signals to the main Receiver, which may be standalone or transceiver-based instead. The Receiver, in turn, provides audio for the operator to copy CW, and can feed one or more digital mode decoders for automatic reception too. Receiver functions are variously partitioned between hardware and software depending on your hardware receiver setup and any one or more SDR instances. Receiver imaging for waterfalls and curtain displays help us see band activity and follow QRSS.
Decoders can upload to the internet and update a WSPR2/WSPR15 database at a central server. Internet connectivity can screen-share your JT9 decoded information with other MF/LF stations. The Decoders section also includes an interface to permit remote control and protective commands to your station such as from a smart phone. “Meep-meep” heads-up signaling from ON4KST reflector is internet-deliverable. Operator notifications of propagation excursions and/or terrestrial storm conditions can be automatically given via internet.
Now we reach the Station Control section. Station Control in the past and primarily even now means the intelligent human operator. You manually control the station by adjusting tuning dials and actuating panel buttons, and by manipulating keyboard and mouse, and operating with a CW key and possibly a station control foot pedal. Voice control may also be used with care. Station control effectiveness and convenience are enhanced with various types of interlocks, relays or equivalent hardware circuits, software features, etc. Antenna rotation, antenna selection and/or antenna pattern control are further included in Pre-RX and Station Control.
In recent years we see increasing amounts of machine-based automation and machine intelligence*** applied in ad hoc modules or more comprehensively for the Station Control. Timing can start up and stop beaconing operations, change transmit percentage TxPct, and support station operations that adapt to band conditions as detected by Receiver and Decoders. Perhaps we will see some form of automatic retuning in QSY Control in the Post-TX section, if a station isn’t already doing it!
At the other end of the automation spectrum, some station strategies try to get rid of as much complication as possible: Provide a receive antenna that needs no outdoor RX preamp. For TX and RX, do all their coupling and tuning indoors or as close to indoors as possible.^ Run the antennas at low enough efficiency (or low system Q) so that QSY involves no retuning at Post-TX or Pre-RX.^^ Do almost everything manually.
Tell us your techniques and solutions for various parts of LF/MF station construction and control. Send us schematics – elegant or ugly, sophisticated or modest – if you have them. We look forward to blogging them!”
*See blogs on transmit antennas from last season, scroll 30% in http://njdtechnologies.net/a-band-opening-that-spanned-the-globe-vk3elv-kl7l-wh2xcr-vk2xgj-vk3elv-jh3xcu-trans-atlantic-activity-from-europe-to-new-england-that-extends-even-further-south-dk7fc-k4ly-wg2xsv/
**Consider a multi-part lightning series: http://njdtechnologies.net/big-night-for-trans-atlantic-reports-including-g0mrfs-portable-operation-dk7fc-ua0snv-wsq2-action-in-the-pacific-northwest-stormy-night-in-vk-results-in-one-pacific-dx-report-for-wh2xcr/ (scroll 40%)
***See smart controls and machine intelligence; start at minute 6:15 of this video: https://www.youtube.com/watch?v=Bwk-r8AJBR0&feature=youtu.be
^Compare WI2XBQ one-turn shack-tuned active loop blogged Sept. 28:
Additions, corrections, clarifications, etc? Send me a message on the Contact page or directly to KB5NJD gmail dot (com).