A brief summary of the military, commercial, and Amateur uses of meteor burst communications has been written by Sascha Segan for ABCNEWS.COM. While short and with only a couple of lines about Amateur work, Sascha has done his homework and it has a good background on commercial and military uses. You can find it on ABCNEWS.COM's Web site. Worth reading.
(If you're interested in learning more about the history of MS, and also some theory behind meteor burst communications, see the several text files bundled with OH5IY's MS-Soft program.
Summary of inititial visual reports from the IMO -
Rates start rising around Nov 17, 2200 UTC, and reach values above 200 from about Nov 18, 0130 UTC onward. ZHRs continue to rise until they almost reach the value of 300 around Nov 18, 0345 +/- 15m UTC. Afterwards, the rates drop again. Towards the end of the European observing window, rates no longer fall and tend to increase again. This increase is matched with the start of the American observing window which starts with a steady increase in rates reaching the value of 300 already around Nov 18, 0530 UTC. Rates continue to rise to a level of 450 around Nov 18, 0715 +/- 15m UTC.
More information available at a lot of Web sites. Try http://science.nasa.gov/headlines/y2000/ast21nov_1.htm?list133415 for a start.
(To see a very interesting graph on this from the Ondrejov backscatter radar, go to http://www.asu.cas.cz/~koten/radar.html).
PROSPECTS FOR NEXT YEAR: There are again predictions for multiple Leonid peaks in 2001, with probable storms. During November 18 and 19, the Earth is predicted to interact with several different trails of dust ejected by Comet Tempel-Tuttle from the years 1666, 1699, 1799 and 1833. Highest activity is expected over eastern Asia and Australia soon after 1800 UTC on November 18, where some forecasts are suggesting rates of up to 15,000/hr!
For North America, the one encounter that seems to yield the greatest promise for high activity is the 7-revolution dust trail (shed in 1767). There are three specific predictions for this trail that have been published . . . all of which are very close in both the predicted peak times and predicted hourly rates. The time of this peak is approximately November 18, 1000 UTC.
To see the predicted times and rates, possibilities for 2001 and 2002, plus lots more background information, go to the Leonids 2000 page (and also follow the links). NOTE - the information concerning the possible peaks for the next two years will be updated with more details on these pages as soon as possible. Please check back.
NEW OPERATORS - remember that there is a large number of papers, many necessary, on both the W8WN Web site and the W6/PAØZN Main NA HSCW Web Site.
For this Web site, go to the W8WN HSCW Home Page (or, if you just came from there, go BACK to it so that the frame display will be correct). Then look under PAPERS, ANTENNAS, MSDSP, and/or PROPAGATION, etc, to find them.
The really necessary paper for U.S and Canadian Hams is the North American "Procedures" ("HSCW-SOP"). Also needed are the "Operating Chart," "Semi-Technical FAQ," and whatever others you need to fill in the gaps.
To keep up with happings on HSCW (and also MS in general), it is strongly suggested that you join the HSCW Reflector (primarily North America) and the meteor-scatter Reflector (primarily Europe, though much overlap now on both). These are where most HSCW announcements and skeds take place, as you will not find much HSCW discussion on the general weak-signal VHF reflectors (and very little concerning anything on MS, except during the handful of major showers. At this time the WSVHF Reflector becomes quite heavy with schedule requests, etc).
To join the HSCW Reflector, send a message to [email protected] with the text, subscribe hsms.
To join the meteor-scatter reflector, send a message to [email protected] with the text, subscribe meteor-scatter.
To join the WSVHF Reflector, send a message to [email protected] with the text, subscribe wsvhf.
And, of course, check out the Ping Jockey, "Hot Rocks" and European MS real-time MS Web sites (and also the several other real-time VHF propagation sites linked from there).
(Most North American non-MS propagation notes, etc, seem to be on the WSVHF Reflector, another of the qth.net reflectors).
North American HSCW Ops - be sure to Register so that we know you're there! Go to the NA List Directory and sign in!
Both NA and European ops, sign in on the World Wide listing, available from the "Make More Miles on VHF" Web site.
Here is Clint's final report of his 144 MHz HSCW MS operation from this trip. (He also operated some 144 MHz and 10 GHZ tropo scatter operation plus some 50 MHz SSB MS, but we have no information on his contacts on these bands and modes).
See new photo of his ship, in the shipyard. Look to the right of the stack, you may be able to see his antennas (150 K).
Hear portion of overdense burst on W4WHN, EL96, as received by W1LP/MM, EK30, in the Pacific. (0.8 sec, WAVE file, 36 K, so will take a while to download. Or, in MP3 file, 15 K. 6000 LPM, FB sig! Full speed - you'll have to copy it yourself, as the file would be too big at an easy speed of 25 wpm).
"Here is a list of stations and the grids I worked them from over the past 5 weeks via 2M HSCW from the Paciific, Caribean, Gulf of Mexico, and East Coast. About 2/3 of the contacts are from calling CQ. The other 1/3 were made during skeds. My ship is now in the shipyard in Houston where it will be until late January. I'll be going home in late Novenmber and will return to the ship in March 2001.
W1FIG (FN41) FM12,EM90
K2TXB (FM29) EL47,EL56,EL65,EL66,EL74,EL84,FL06
W4WHN (EL94) EK30,EK96,EL47,FM36
KM5ES (EM25) EL56,EL75,EL84
W5HUQ (EM35) EL75,EL84
W5SNX (EM73) EL47,EL56,EL65,EL66
W8WN (EM77) EL37,EL47,EL48,EL56,EL65,EL66,EL71,EL75,EL84,FM13
K9KNW (EL95) EK40,EL47,FM13,FM36,FM38
K0PW (EN34) EL37,EM91,FM12,FM25
KM0T (EN13) EL37
N0UK (EN34) EL37
The annual Perseids activity was interrupted Saturday morning (August 12) by a big aurora! Reports indicate that it was seen/heard as far south as LA. (VE3AX was heard working W5RCI, Marks, MI). Because of operators getting up early for MS skeds, the activity was high for that time of day. The Europeans indicated that their radio aurora disappeared about 0800 Z, followed by a brief period of auroral-E. There was some auroral-E reported from the central or western part of North America, also. Several reports tell of great visual auroral displays across the northern Midwest states, and Rocky Mountain operators reported hearing East Coast stations. One Amateur had a broad auroral curtain with a number of meteors streaking past. An interesting morning!
For more, see notes from the NASA Science News (has some great pictures).
(Notes on the April 6 Aurora and July 15 aurora can still be found on the Archive page).
A few reports, primarily from North America, indicate that the Perseids meteor shower this year was not exceptional; but a few other reports, especially from Europe, seem to describe a "normal" shower for the "old standard" Perseids. Both visual and radio reports tell of a fair number of very long, strong burns. There are reports of a large number of quickly-completed contacts, some using only low power.
The peak times for this year's Perseids were predicted to be about 0500 Z for the early peak and 1000 Z for the main peak. Europeans report a sharp, early peak at about 0530 Z and a normal, broad peak about 1000 Z. However, first visual reports to the IMO indicate that there was no early peak seen. This is the first time in the 10 years since the return of the parent comet that the early peak failed to appear (if, in fact, it actually was not present - first visual reports are sparse at the expected time of the early peak). Very little had been expected from the early peak this year, as it had been decreasing in strength the past few years.
The best pings and bursts were noted here (central KY) between about 1400 and 1530 Z.
Was the peak really a little late, or was the aurora to blame for this? Or perhaps there were just a few little filaments giving some extra enhancement at that time? There was no random MS activity heard during most of the aurora, as everybody was busy with it. Routine schedules continued, however. When did you experience the second (main) peak?
Two noteworthy MS contacts was made over a distance greater than 1400 miles (2250 km); one of these may be a new North American HSCW DX record on 144 MHz (we now have at least 3 recent HSCW contacts within a few miles of the same distance, depending somewhat on the accuracy of the coordinates of each station). WØAH had two "near misses" on SSB over 1400 miles. There apparently were a number of other contacts at longer than average distances. (Anything beyond 1400 miles via MS is exceptional, and would have been considered nearly impossible in the past.
Several 222 MHz contacts were completed this year, often very quickly! We have heard of several 432 MHz schedules on the 13th, but no contacts have been reported.
See the link on the next item (and bookmark it - it's very good!), as well as links near the bottom of this page, for more information on the shower and aurora.
Old Sol does it again! The most intense geomagnetic, auroral and solar radiation storm of solar cycle 23 brought the largest auroral storm since the March 1989 event, surpassing the April 2000 aurora. July 15 produced contacts at least as far south as central Texas, Mississippi, and Georgia. N4IS, EL96, southern Florida, reported hearing some weak auroral signals, but was unable to work anyone. A number of stations are reporting 50-70 QSO's in 40 to 50 grids all the way from the East Coast to the Rocky Mountains!
This was an extremely powerful geomagnetic storm. On the 15th, the panetary A index reached 152 and the mid-latitude A index was 148. The planetary K index reached 9 for at least a 9-hour period! This was one of those extremely rare events that happens only a few times each sunspot cycle. At least one satellite, the Japanese ASCA X-ray observatory, is in serious trouble because of the solar storm.
For animations of the CME, as recorded by the Solar and Heliospheric Observator, go to http://sohowww.nasacom.nasa.gov/data/CME/.
(Also, the June, 1968 issue of Sky and Telescope had a map which shows how far south the aurora may be visible, dpending on the planetary K index. It can be found at http://www.sec.noaa.gov/info/kp-aurora.html).
For a brief explanation of these parameters, see K7VVV's summary.
N6CL, CQ's VHF Editor, will have a sidebar in the September issue of CQ and a more extensive report in the October issue. No doubt W3EP will do likewise in QST.
Will there be more auroras? We're near the peak of the current solar cycle, so it might be well to subscribe to one of the auroral alerting services! (Send message to [email protected] with the text, subscribe sun-earth. Or, to [email protected] with the text, subscribe rwc-aurora-alert. Either of these services, and others, will give timely alerts by automated E-mail. Of course, for those living in central and southern latitudes, most of the auroras won't be big enough to do us any good. But they certainly aren't of any value if we aren't on the air!)Several people have asked for more information on the huge March 1989 solar storm. Here are several Web sites that have a little info:
K9KNW/MM went fishing over the Labor Day weekend. While in EL85, he was caught on HSCW by a number of fellows for another new all-water grid. Thanks, Joe (and thanks, Dean, for setting up the skeds).
The April 6 AURORA was the largest of the current sunspot cycle, and probably the largest in the past 10 years. The peak of this sunspot cycle is predicted for this summer. While it is not expected to be quite as high as the last two, we should see a number of auroras, 50 MHz F2 openings, and other "goodies" that VHF operators look forward to! However, remember that the solar activity that produces the good effects can also produce some detrimental events. Several satellites were damaged by radiation during the last peak, and LEO satellites had their orbits pushed closer to the earth resulting in the premature re-entry of several. And don't forget the Hydro Quebec power outage in March 1989, where power was lost to more than 6 million people! Since then, steps have been taken to harden satellite electronics and to protect the power grids. But don't sell all those Y2K supplies too early! We rely even more on these highly technical gizmos than we did in 1989, and Old Sol could throw us another damaging blast!Description, with a lot of photographs. NASA Science News has collected about 40 images of the aurora. Go to today's NASA News page for a look.
The three-year series of 144 MHz HSCW MS schedules between W8WN (EM77bq) and KØXP / KOØU (FN42dg) has ended for now due to KØXP's move. The schedules began in May, 1997, at 250-400 lpm (50-80 wpm), receiving by ear and transmitting with a programmable keyer or OH5IY's "MSSoft" program. DL3JIN's "SBMS" HSCW receiving program was discovered, and it was immediately put into use. In July 1997 9A4GL released his first beta (receive only) version of "MSDSP". This was followed by a number of other versions, which soon also had transmit capability. By the end of 1997, contacts had been completed at speeds up to 8500 lpm (1700 wpm).Other North American stations were becoming interested in HSCW. Several were using "CoolEdit", but most were using MSDSP. (HSCW had been attempted a few times previously in North America, but few if any contacts were ever made due to the lack of activity. It's hard to complete a contact when there's nobody available on the other end!) It quickly became obvious that the procedures in use for SSB and slow-CW MS were inadequate for HSCW MS operation. However, even though HSCW MS was in its infancy in North America, routine schedule speeds were already higher than those in use in Europe. So W8WN and KOØU, among others, began experimenting with HSCW procedures, attempting to preserve as much of the structure and format of the Western Hemisphere's 40-year-old traditions, but also taking the best of the European HSCW methods. Ideas were then discussed, sometimes at length, among the active HSCW stations. Eventually, a set of North American procedures fell into place (found in Procedures). For the first two years, however, most of the schedule time was taken up testing various versions of 9A4GL's DOS versions of MSDSP. Tihomir spent a lot of time working on the program, and he was always receptive to our comments, ideas, and requests. (He eventually put in almost everything we requested!) But this was a difficult program, and it required many versions before it became stable enough for reliable operation. Each version had to be tested in as many ways as possible, looking for bugs that had slipped in while correcting other problems. W8WN and KOØU were two of the dozen or so Beta testers for all versions of MSDSP, so testing the various versions was the most important work for much of this three-year period. Because of the tests of MSDSP, tests of the limits of unmodified equipment capabilities, tests of new procedures, and general checks on MS conditions day by day, no great effort was made to actually complete each contact, though normal procedures were usually followed. The schedules usually ran 5 days per week, depending upon the availability of both operators. Normal sked length was 15-20 minutes, due to other committments, but with a few running as much as 30 minutes. (It was not unusual to complete a contact in 4 to 10 minutes on a good day, but 15 minutes was the nominal schedule length). Here is a brief summary of the schedules. (Numbers may not be exact, but are very close). When one station was on but the other was not able to be there, for this summary it was not counted as an attempt.
HSCW on 50 MHz? A series of skeds has just been run by K1JT (FN20) and W8WN (EM77). Both were running about 100 watts to 4-element Yagis. In spite of the poor sporadic MS conditions expected this time of year, contacts were completed in 6-12 minutes every time. Compared with the same path on 144 MHz, pings were much weaker and longer on 50 MHz. Instead of fractional-second pings, most were about a second in length. (The actual number of pings was about the same on both bands, with too much day-by-day variation to determine further). The reason for the weaker signals on 6 meters was probably due to the much lower gain of the antennas - on 144 MHz, K1JT runs a single 12-element Yagi while W8WN runs a quad array of 16-element KLM Yagis. K1JT runs about the same power on both bands while W8WN normally runs about 1 Kw on 144. (See the next note for more).WANTED FOR SKEDS - Someone about 600-1000 miles/1000-1600 km distant from EM77 who can transmit (or receive) on both 144 and 50 MHz HSCW at the same time, as several people would like an actual same ping comparison between 144 and 50 MHz. Contact W8WN.
More information on the "soft keying" when using MSDSP at speeds higher than 10,000 lpm.
It has long been observed that at keying speeds of 10,000 lpm (2000 wpm) or less, signals are normally very easy to read when slowed down. But at 12,000 lpm and higher, copy becomes difficult because it is hard for the ear to separate the elements of the code. In other words, the keying sounds "soft" when slowed down and played back. Yet experimental contacts have been made at speeds up to 16,600 lpm (the maximum speed of the DOS version of MSDSP), even though the signal-to-noise ratio also seems to become poorer at these speeds. The reason for the "soft keying" was not known for sure. But, due to the loss of S/N ratio at the very high speeds, few additional tests had been run.
However, as the typical schedule speed has increased to 6000 lpm, and a number of recent schedules have been run at speeds up to 10,000 lpm, interest has increased in going even faster to take advantage of the very shortest pings.
At 12,000 lpm, as had previously been observed, keying seemed "soft." Now several more tests have recently been run.
The first set of tests consisted of feeding the transmit signal of WinMSDSP from one computer directly into another computer, running either WinMSDSP or the DOS version. Upon playback, the keying remained sharp with no signs of mushy or fuzzy leading edges, even at speeds up to 20,000 lpm (4000 wpm)!
The second set of tests consisted of transmitting from one computer and transmitter to a separate receiver and computer, side by side. Different speeds, tone injection frequencies, receive tones, IF Shift settings, etc were tried. At speeds of about 14,000 lpm the keying was slightly softer, but the ringing caused by heterodyning the converted signal was becoming bad. At 20,000 lpm, the signal was unreadable in nearly every test. (These tests have now been run by two different stations using completely different equipment, but with very similar results).
More tests need to be run, attempting to discover what changes can be made, if any, to improve readability at speeds of 12,000 lpm and higher. With the SSB filters commonly used by modern rigs, sharp keying at these speeds may not be possible. But we will not know until additional tests are run. If you are interested, here are several notes:
1. Several contacts have been made in the past between 15,000 and 18,600 lpm. The S/N loss and ringing were bigger problems than the soft keying. However, these were all made using the DOS version of MSDSP at each end. (The injected tone was 2500 kHz. SampleRate was probably 44100, tho it might have been 22050). Is there a difference between the DOS and Windows versions of MSDSP here, or was this just "beginners' luck"? (The generated tones are somewhat different).
2. The filters in most modern SSB rigs begin their roll-off at about 2.1 kHz.
3. In order for MSDSP's dits to be a full sine-wave cycle, the injection frequency must be raised as the speed is increased. (Tnx to VE5UF for the following table):
LPM Rate Dit length Frequency 10,000 600 1666.67 Hz 15,000 400 2500.00 Hz 20,000 300 3333.33 Hz
The information is now in - we have a new North American HSCW distance record. KMØT (EN13vc) and K9KNW (EL95dx) completed an HSCW contact during the Leonids over a distance of about 1434 miles or 2307.764 km. The contact, on 1999 November 18, required an hour, at 6000 lpm. The previous record was 1433 miles or 2306.385 km (K2TXB and NØKQY). These distances were determined using BD and locations measured by GPS receivers. There's only about one km difference! Congratulations to all in working at these distances! 1400 miles has always been the "wall" for MS work in North America, with contacts beyond that distance considered a near impossibility. Now, in the past year, there have been at least 3 contacts beyond this distance, all using HSCW. Who will be the first to work beyond 1500 miles/2400 km?
A very inexpensive programmable keyer kit, capable of HSCW operation, is now available. K1EL has recently released his "K10" single-chip semi-kit. Speeds of 5-59 wpm and 1000, 2000, 4000, and 6000 lpm, with provisions for output of a keyed tone (apparently square wave). Cost is very reasonable. Operation is said to be very smooth, and one is currently being used on the air for HSCW. A few additional programming changes are said to be in progress. For more information, go to K1EL's Web site at http://members.aol.com/k1el/ .
Some very good questions about MS, operating, and showers have recently been asked not only by people new to MS, but also by some experienced operators. Good explanations are found in the paper MOREON50.TXT, which is part of the OH5IY MS-Soft package, available from his Web site. I strongly suggest that you again read this very interesting paper.
Another source is The RSGB VHF/UHF DX Book (available from the ARRL). While not as complete in some areas as the old ARRL VHF Handbooks, it is current, with good MS and HSCW info. (Remember that some of the Region 1 Procedures are the reverse of ours in North America).
Necessary for anyone seriously interested in any form of VHF/UHF propagation is Beyond Line of Sight from ARRL. It contains reprints of nearly all the important VHF propagation articles from QST.
Other references are listed at the end of the "Semi-Technical FAQ", available on the W6/PA0ZN Web site.