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I operate high speed digital meteor scatter on 50 and 144 MHz from home and the car (see photo right) using the incredible WSJT software. The southwestern desert isn't the best place for 2-m DX -- tropo is all but non-existent here and I understand 2-m sporadic E makes its way into New Mexico about once every five years. That's what they tell me anyway. I've actually heard cw aurora signals, but have yet to complete a QSO on that mode. I'm too far south to hope for much aurora. Sporadic meteors, on the other hand, are there pretty much all year round. You can work DX if you have the patience. Here's a map of Grids Worked from my home station using FSK441 HSMS on 144 MHz. I'm located in Albuquerque, NM (small red circle) in Grid DM65. 72 grids; last updated August, 2009. Best MS DX: 1278 miles, VE7SL, Grid CN88. The pattern on the above map is primarily a reflection of available and suitably equipped HSMS operators. To a lesser extent it is influenced by meteor conditions and topography, particularly the 10,000 foot Sandia Mountain Range to my immediate east. My experience is that the ideal range for meteor scatter contacts is something like 650--1000 miles. If you are anywhere in the western USA or Canada you should be able to hear me on 144 MHz, although DX past 1100 miles is going to be tough without one of the annual meteor showers. Please contact me if you would like to schedule a QSO attempt. Note: I have too much city noise to do moonrise/moonset EME with anyone not running a mega-station. On September 3, 2007 I heard and recorded an amazing meteor burst on 144 MHz. This occured during a scheduled WSJT run with N0PB in Missouri, about 850 miles distant. It was early in the run and Phil heard a loud, sustained signal from me right at the end of my 30 second transmit period. He quickly realized this was a very rare long-burn that could possibly support an SSB QSO. In this audio file, you will first hear message 1 of the FSK441 sequence (both callsigns), followed by Phil clearly calling me on SSB. I was too stunned to switch over to SSB in time to call him back (this would have required me to stop WSJT, push two buttons, and grab the microphone!). In the same period, just seconds later, Phil had WSJT back running with both callsigns and report (message 2). This is an example of extremely alert and skillful operating by N0PB. The QSO was completed digitally on the next two periods. It all took place in non-meteor shower conditions and there was no Es or tropo-enhancement. Rover. I first got interested in WSJT for making meteor scatter contacts with my rover setup. You can read all about that by clicking here. I've been all over New Mexico on mini grid expeditions. I have made meteor scatter contacts from the following grids while portable: DM55, DM64, DM65, DM66, DM73, DM74, DM75, and DM84. A map of the grids I've worked on 2-meters using portable WSJT meteor scatter can be seen here. When portable, I use a deep-cycle battery to run all the gear including the computer. To conserve the battery, I keep the rf power below 50 Watts. The antenna is a 5-element beam mounted 15 feet off the pavement; on a few occasions I have used stacked 5-element beams. Compared to my home station, the portable operation is puny. But experience shows I do much better with the rover than from home. The trick is, of course, finding high altitude operating locations away from all the man-made noise. And that's pretty easy to do in New Mexico. The experience of meteor scatter operators is that pings are longer and more frequent on 50 compared to 144 MHz. This has to do with ionization in the E-layer and is essentially the same reason sporadic-E openings are much rarer on 2-m. An understanding of E-layer reflection at VHF frequencies can be gained with elementary plasma physics; a textbook calculation of the problem is outlined in this document. Go back to WB2FKO home page. |
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