November 2000 QST

More documents

Recommendations

Info

(in the clear) are quite usable. A quiet location is always an asset. Don’t worry about hacking up your SSB rig—no mods are needed. Keying is accomplished via audio tones (similar to most digital modes), and standard SSB filters work fine up to about 10,000 LPM (2000 WPM). The emission designator— J2A—produces keying that is indistinguishable from keying the main carrier. It’s the same method used by many rigs to produce CW. 13 Using standard SSB filters, the bandwidth of an HSCW signal is about the same as that of a voice transmission. For more technical information, see the numerous papers on the HSCW Web sites and the resources listed in the article by Jim McMasters, KD5BUR (now KM5PO). 14 HSCW MS operation is decidedly different from conventional CW or SSB meteor-scatter operation. Both require overdense bursts or good (strong and long) underdense pings to complete a contact. SSB and slow CW operators hope for specular reflections from heavily ionized trails instead of “the abominable ping,” as one writer put it. Unfortunately, overdense bursts are usually observed only during major meteor showers. HSCW relies on the numerous subsecond bursts and the weak pings scattered from underdense particle trains. Pings of this type are often produced by the “sporadic” particles that constantly bombard the earth. Most of the debris that the earth “sweeps” into as it orbits the sun are not fragments from the asteroid belt but are particles from the dust trails left by ancient comets. The particles are widely distributed and no longer dense enough to produce recognizable showers. Their number may vary significantly from day to day—and even minute to minute. Most of these particles are no larger than grains of sand or specks of dust, but because of their extreme speed, the ionization they produce as they burn in the atmosphere is often enough to scatter or even refract radio waves. 15 The duration of these pings is usually very short, but the number of tiny pings available on many mornings may surprise you. It’s been estimated that if you have a 5% chance of completing a contact on SSB, your odds improve to 95% on HSCW. Of the approximately 215 completed HSCW contacts between W8WN and KO0U/K0XP, no more than 10 contacts could have been accomplished on SSB. Nearly all of those would have taken place during showers, when SSB MS comes into its own. Meteor scatter (using any mode) is difficult at distances of less than 500 miles (800 km) or greater than 1400 miles (2250 km) because of the height of the meteor trails, antenna characteristics, the 30 November 2000 An 11-element Yagi on telescoping paint pole for portable operation at our son Steve’s home near Clio, Michigan. The “basement-portable” operating position at Clio, Michigan. The hardware includes an IC-706 MKII transceiver, 150-W amp, MFJ switching power supply, Bird wattmeter, GW2K laptop computer running WinMSDSP, audio filter and coffee cup! Notice the very fancy recycled cardboard box operating table they gave me! WinMSDSP. Here we have the main MSDSP screen, and the flutter-type QSB on an overdense burst (burst length, 8.9 sec). scattering mechanism, etc. 16 For close-in communication, back- or side-scatter techniques (or antennas that can be aimed in elevation and azimuth) are usually needed. At distances beyond 1400 miles, a good location and plenty of power are necessary. Although difficult, unusually long and short QSO paths are possible during showers. Because HSCW relies entirely on signals scattered from underdense meteor trains, the typical sporadic ping will be weak and very short. So, when it comes to output power— the more the merrier. Does this mean that a 150-W station can’t take advantage of sporadic underdense pings To see what could be done, I talked my daughter, WD8KVD, into letting me operate portable from her home near Duluth, Minnesota, when I visited in July of 1999. My IC-706 transceiver drove a 150-W amplifier and an 11-element Yagi that was mounted on a telescoping paint pole about 20 feet (6 meters) above the ground. The location was merely fair for VHF. I used an old laptop computer to run the Windows or DOS version of MSDSP. 17 Compared with the kilowatt and the large array at home in Kentucky, contacts were more difficult, of course, but a number of ops were able to add a new grid to their logs. An indoor portable operation was repeated at Christmas 1999 from my son’s home near Clio, Michigan (EN83). Using the same equipment but with very flat terrain, contacts between 500 and 1000 miles were easily made. (Details and photos from both operations are available on the W8WN Web site. 18 ) Since then, K9KNW/MM has completed a number HSCW contacts from his boat, running either a halo or a small beam. During May of 2000, K9KNW completed 28 HSCW contacts while sailing in seven water grids (EL93, FL03, 13, 14, 15, 23 and 24). His 12-element Yagi was only about three meters above the water, limiting his maximum QSO distance to about 1250 miles (2000 km). Stations less than 1100 miles (1775 km) distant found the contacts to be quite easy, usually taking less than 20 minutes. Those at greater distances were more difficult. Joe has plans for more trips, including a possible grid-hopping trip with much more time devoted to Amateur Radio. How Fast is Fast Obviously, higher-speed transmissions can pack more information into each ping. MS speeds were originally 25-35 WPM (still the standard for slow CW operation). Several pioneer operators could operate at 50 WPM, copying in their heads. When the Europeans developed HSCW, routine speeds increased to 2000 LPM (400 WPM) or more. The current version of WinMSDSP is capable of speeds up to 20,000 LPM (4000 WPM). But are these extreme speeds practicable And what is the maximum usable speed Although contacts have been made at higher speeds, the practical MS speed limit is about 12,000 LPM (2400 WPM) (using unmodified SSB transceivers with standard SSB filters and audio tone keying). At higher speeds, the signal-to-noise ratio degrades and the keying begins to sound “soft” and indistinct. Remember that, using a 2000-Hz injection tone and receiving with a 1500-Hz tone, a single dit may not even occupy a full audio cycle! By using wider filters and higher tone frequencies, faster data rates may be possible, but none of the MSDSP test
HSMS Bounty…K9KNW/MM Provides Rare Caribbean Grids to VHF Meteor Enthusiasts Joe Goggin, K9KNW, is an avid deep sea fisherman. His love for that sport is second only to his love for VHF meteor-scatter operation. From May 19 through June 16, 2000, Joe managed to combine a fishing expedition with a 2-meter HSCW MS operation and provided some exciting QSOs and very rare Caribbean grid squares to North American HSMS operators. The robust nature of HSMS techniques allowed K9KNW/MM to operate from seven rare grid squares and complete 29 QSOs. Some contacts were completed in 20 minutes or less, while others took up to an hour to complete the required exchange of information (call signs, signal reports and acknowledgements). Morning operations were the rule, as sporadic meteors—the cosmic debris that provides HSMS operators with day-to-day airborne signal reflectors even in the absence of meteor showers—are most plentiful during the hours around local sunrise. Simple geometry—the height of the meteor trails—determined which US stations were within range of Joe’s reflected signals. The current North American HSMS distance record (anchored on one end by K9KNW from his home station) is a little more than 1400 miles. VHF operators located along the Eastern seaboard and much of the lower Midwest could have—had they been active on HSMS—picked up a handful of very rare grid squares. K9KNW/MM activated grid squares FL03, FL13, FL14, FL15, FL23, FL24 and EL93. Joe worked WB5APD (in EM84) and W5SNX (in EM73) from every one of those grid squares. “Those two guys both had good signals, but, Bob Dodson, WB5APD, pounded me with pings in every grid.” Dodson and Dick Ray, W5SNX, operate sophisticated 2-meter stations and use high transmitter power and large antennas. Both were positioned within ideal MS range of Goggin’s floating station. “But, I also worked Joe Taylor, K1JT, in FN20 from FL23, a distance of about 1164 miles,” says Goggin, “and he runs a modest station (160 W to a single 11-element Yagi), which proves that you don’t need high power and big antennas to enjoy HSMS.” The long-distance QSO champ for this voyage was W9FX, located in EM57. K9KNW/MM was in FL23, and the calculated distance for that QSO, based on K9KNW’s GPS coordinates, was 1256.1 statute miles. Other successful HSMS operators were W8WN, K2TXB and W4WSR. Goggin said he was “a little disappointed in the light turnout of stations who expressed an interest in working me. But since there wasn’t any advance publicity for this trip and it was my first time out, I guess that’s to be expected. For future trips, some of which may be tailored strictly as HSMS DXpeditions, I’ll try to get the word out in advance so that more stations will have the opportunity to join in the fun.” HSMS operations are, for the most part, arranged in advance by sked. Dean Nickless, W4WHN, served as the primary land-based contact (‘pilot’ station in DXpedition terms) for the hungry grid hunters. W9FX filled in when Dean wasn’t available. Sked arrangements made on the internet by HSMS operators were passed to Joe via 2-meter SSB or 20-meter PSK31. “Not having an internet hookup on the boat slowed things down. I’m going to have to see about equipping her with satellite-based internet access,” Goggin stated. K9KNW/MM operated from a custom-built 65-foot sport fisherman, the Island Gyspy. The wood hulled, twin diesel beauty with her 20-foot beam provided a relatively stable platform for Joe’s 2-meter Yagi. Despite the fact that that all of his HSMS operations were conducted while at anchor, the Caribbean wind and waves did pose a unique antenna pointing problem. Joe says, “The boat was constantly changing position. I had to keep one eye on the computer screen and the other on the compass and rotator.” “This trip didn’t demand much planning. We simply loaded supplies on board and took off,” said Goggin. “That’s why I didn’t post an itinerary or publicize the anticipated HSMS operations in advance. There was a lot of thought—and work—involved in figuring out how to mount an effective antenna on the boat without detracting from the operation of the fishing gear or marine electronics.” How was the fishing “Great, “ said Joe. “But,” he added, “I had more fun on 2 meters!”— Brad Pioveson, W9FX, 301 Kirsch St, Benton, IL 62812-1706; w9fx@arrl.net stations had this capability, and no one has had the ambition to purchase new filters or to modify their rigs. Still, North American HSCW speeds are quite peppy! Other Bands HSCW MS operation in North America is mostly limited to 2 meters. Most MS activity takes place there already, and MS work on other bands is too difficult or rather easy, eliminating the need for HSCW altogether. 50 MHz (calling frequency 50.300 MHz): Compared to 2 meters, 6-meter meteor pings tend to be weaker, last longer and somewhat more frequent. The lower-gain antennas and reduced transmitter outputs typically used on 6 meters apparently account for the drop in signal strength. On 6, pings average about one second in length, with occasional pings of five or more seconds. This is why SSB MS is possible many mornings on 6 meters between wellequipped operators. Also, with E s , F 2, tropo and other propagation modes, grids can eventually be worked even without cooperative meteor fragments. Surprisingly, HSCW MS isn’t all that easy on 50 MHz because of the weak signals. Most operators find 144 MHz to be more workable, making HSCW a relative rarity on the magic band. 222 MHz (no random operating; schedules only): As frequency increases, so does the difficulty. On 222 MHz, bursts can be strong but are fewer in number than on 2 meters. One-hour schedules are typical between well-equipped stations. Little HSCW operation has been done on this band, but more is expected this year. In fact, the first known HSCW MS contact was made on May 2 between N7STU and N0KQY—as this article was being prepared. The next day a second 222-MHz contact was completed between N7STU and K0GU. N7STU was running 450 W to a 7-wavelength Yagi, while K0GU had only 25 W to a 22-element Yagi! 432 MHz (no random operating; schedules only): MS QSOs on this band are difficult, but possible. Most 432-MHz MS activity has taken place in Europe. An MS QSO between SM3AKW and UA9FAD (some 2141 km) is believed to be the world record. The North American record (at 2036 km), held by N6RMJ and W7XU, isn’t far behind. Working meteor scatter here takes power and patience. Pings are infrequent and usually short and weak. Schedules are typically one or two hours during showers. The most successful ops elevate their antennas to null out as much ground noise as possible. Also, the notes about antenna aiming and using the “hot spot” should be carefully considered because of the extremely narrow beamwidth of 70-cm long Yagis. Higher frequencies: These bands are generally considered to be unlikely candidates for MS operation, although 902 MHz QSOs should be possible between well-equipped operators during major showers. Using WinMSDSP Although modified cassette recorders and other means are used for HSCW operation, WinMSDSP has become the standard. A limited run-time version (shareware) can be downloaded from the 9A4GL web site and other locations. The software requires a computer running Windows 9x and supporting DirectX (additional operating system “helper” files may also need to be downloaded). WinMSDSP should run with most fullduplex sound cards that support DirectX. The program is easy to use and requires only a few minutes to learn. It’s loaded with features, however, so refer to the brief Manual and the Problems paper (actually, an FAQ) as you do the intial set up. November 2000 31
Page 6 and 7: November 2000 Volume 84 Number 11
Page 11 and 12: THE AMERICAN RADIO RELAY LEAGUE INC
Page 14: Get to Know Your Section Manager Th
Page 18: The FCC Office of Engineering and T
Page 22 and 23: When it’s Kid’s Day, everyone g
Page 26 and 27: CORRESPONDENCE Your opinions count!
Page 30 and 31: By Shelby Ennis, W8WN Utilizing the
Page 34 and 35: Many of the HSCW web sites have a f
Page 36 and 37: By L. B. Cebik, W4RNL A Beginner’
Page 38 and 39: might be very close to zero. As we
Page 40 and 41: “take-off” angle—reported by
Page 42 and 43: Figure 1—Schematic of the flexibl
Page 44 and 45: accessory jack LINE input. If you
Page 46 and 47: fill in other required information
Page 48 and 49: created using SDCHECK, the separate
Page 50 and 51: WORKBENCH PROJECTS AND INFORMATION
Page 52 and 53: THE HELP DESK The relationships bet
Page 54 and 55: Ham University As someone who teach
Page 56 and 57: 54 November 2000 Figure 1
Page 58 and 59: Table 1 KISS TNC DB9 Connector Pin-
Page 60 and 61: RITTY 4.0 Several years ago, Brian
Page 62 and 63: The ONV fullbody climbing harness.
Page 64 and 65: HINTS & KINKS STRENGTHEN YOUR CUSHC
Page 66 and 67: PRODUCT REVIEW Yaesu MARK-V FT-1000
Page 68 and 69: 0 -10 -20 -30 -40 -50 -60 -70 Refer
Page 70 and 71: portation” of the MARK-V during s
Page 72 and 73: The NorCal SMK-1 QRP Transceiver Ki
Page 74 and 75: Astronaut Ed Lu, KC5WKJ, checks sup
Page 76 and 77: ment there. Larry Kayser, VA3LK, an
Page 78 and 79: excellent exposure for Amateur Radi
Page 80 and 81: The team will be QRV from the islan
Page 82 and 83:
2-meter FM DXing. Taiwanese 2-meter
Page 84 and 85:
completed the first-ever 222 HSCW m
Page 86 and 87:
RADIOS TO GO The Good and The Bad I
Page 88 and 89:
The Hallicrafters S-1 OLD RADIO One
Page 90 and 91:
QRP POWER The NorCal 40A—an Insta
Page 92 and 93:
November 1925 ◊ The cover illustr
Page 94 and 95:
I-10, follow Hwy 609 S to second li
Page 96 and 97:
General Rules for All ARRL Contests
Page 98 and 99:
2.1.3.2. Low Power: 150-W PEP outpu
Page 100 and 101:
2000 ARRL 160-Meter Contest Rules 1
Page 102 and 103:
Yoshi, JF2FIU, is putting together
Page 104 and 105:
All artists look for ways to expand
Page 106 and 107:
VE3WIB 782,100 1100 237 B VE3BUC 49
Page 108 and 109:
SP9VRY 828 23 12 C SP7VC (at SP7GIQ
Page 116:
Net Freq Time/Daily/UTC QNI QTC QTR
Page 120:
club meeting. BARC celebrated the 3
Page 124:
Net NM Sess QNI QTC QSP NJM WA2OPY
Page 128:
WA1RI, listing the ARRL affiliated
Page 132:
Stu Johnston, NH6DR. Dennis Niles,
Page 136:
something worth while, please let m
Page 140:
AB4XK 116, KF4KSN 106, KE4VBA 101,
Page 154:
QSL CARDS / CALLSIGN NOVELTIES 100
Page 158:
Anderson Powerpole and OEM power co
Page 162:
160 MORSE 0-20 WPM 90 days guarante
show all

November 2000 QST

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?