AmateurRadio.com

It seems that all of my blogspots of late have focused on 630m propagation ... but what has been happening down there recently has been both amazing and somewhat unexpected. With the growing number of active stations listening and transmitting, the band's propagation capabilities and mysteries are quickly revealing themselves.

Last night was a great example but perhaps the WSPRnet prop map illustrates this best.

courtesy: http://wsprnet.org/drupal/wsprnet/map

The amount of North American activity grows each day, especially now that the DX season has arrived. At one point last night, KB5NJD reports over 100 stations either transmitting or reporting via the WSPRnet activity page! With thunderstorm activity gradually shrinking, reception should only get better over the next few months.

Particularly striking was the long haul propagation from VK to North America, with northernmost VK4YB leading the pack. His 90 watt signal made it all the way to VE3IQB, near Ottawa as well as to NO3M, in Pennsylvania! To provide further hope to those that have little room for big receiving antennas, VE3IQB uses a typical small active e-probe antenna, 20' above ground!

courtesy: http://wsprnet.org/drupal/wsprnet/map

This spotlight propagation to the select regions of the east coast is further mystified by the level of geomagnetic activity overnight, with the K index reaching level 5 and higher!

courtesy: http://www.swpc.noaa.gov/

Interestingly, all of this was right over my head, with not a single peep heard here from Roger. Stations across Georgia Strait, VE7BDQ, VE7CNF and VA7MM all reported hearing Roger as well as being heard by him. For the latter two, yesterday and today represent their initial decodes to down under.

I'm theorizing that Roger's signal was arriving today at much lower angles than normal, evidenced by its far-reaching east coast reception and the fact that it couldn't get over my 600' local obstruction to the west. I've always believed that it takes higher angled signal arrival for me to hear Roger and today's events seem to support this.

Exactly what would cause this to be the case, I'll leave to the experts but I imagine that the sudden surge in geomagnetic activity played a significant role in today's very different propagation paths.

Roger was not the only VK lighting-up the map today. A much more detailed account of all the action can be found on the KB5NJD's daily 630m report here ... all very inspirational and hopefully enough to spur even more new activity on the MF band.

Why not give a listen and see what you can hear?

As our sunsets start to come earlier and dawn arrives later and later, the sun's accelerated southerly excursion has brought sudden changes to 630m propagation.





This past weekend's CLE activity saw universally poor propagation as well as weather related QRN from lightning ... but as usual at this time of the year, things can change rapidly. Wednesday's overnight map of my own 630m WSPR activity illustrates why September propagation on LF and MF can often be spectacular and this is with just 65 watts total power output:

courtesy: http://wsprnet.org/drupal/

Among other things, the map indicates the growing interest among U.S. amateurs in the 630m band. Hopefully they won't have to wait too much longer, although I seem to be saying this more often than I would like to. It is of interest to note that even though these were WSPR reports, signal levels at most reporting stations were either into the 'audible CW' levels or at 'JT9 workable' levels ... all stations should be workable once the 630m ham band becomes a reality for all North Americans. Midwinter conditions over the next several years should see an abundance of transcontinental contacts on both CW and on JT9!

The east-west path is the bread and butter direction for interesting possibilities, when it comes to those of us in VE7 land. Normally it only really sets in when geomagnetic conditions are quiet but, as a result of coronal hole streaming, this week's geomagnetic field has been anything but quiet. As John Langridge, KB5NJD / WG2XIQ reported today in his invaluable '630m daily reports':

The geomagnetic field was extremely active, with many reporting periods at storm levels. The Bz is pointing to the South and solar wind velocities are very high, peaking at 700 km/s. This event is significant and I am just glad to see that it is helping and not hurting propagation. When will the bottom drop out? Clearly there is a lot going on here that we do not understand.

With stormy conditions continuing throughout the week, Friday's path to down-under enjoyed some enhancement as well, not unusual when the east-west path is disturbed. VK4YB's 90 watt signal was widely heard by several VE7's (VE7CNF, VA7MM and VE7BDQ) in the predawn hour, as Roger's signal peaked up briefly for several WSPR decodes.

courtesy: http://wsprnet.org/drupal/

As the coronal hole streaming continues, this morning's path to VK seemed even better along with a new antenna at VK4YB favoring the northwest:

12:24      VK4YB      0.475622      -21   VE7BDQ    11844 km      
12:12      VK4YB      0.475621      -22   VE7BDQ    11844 km      
12:08      VK4YB      0.475622      -17   VE7BDQ    11844 km
11:04      VK4YB      0.475622      -24   VE7BDQ    11844 km     
11:02      VK4YB      0.475623      -22   VE7BDQ    11844 km     
10:54      VK4YB      0.475623      -22   VE7BDQ    11844 km

12:28      VK4YB      0.475626      -21    VE7SL       11820 km     
12:24      VK4YB      0.475625      -23    VE7SL       11820 km     
11:54      VK4YB      0.475623      -25    VE7SL       11820 km     
11:04      VK4YB      0.475623      -23    VE7SL       11820 km    
11:02      VK4YB      0.475625      -26    VE7SL       11820 km     
10:54      VK4YB      0.475626      -21    VE7SL       11820 km

11:22      VK4YB      0.475614      -28    VA7MM      11872 km     
11:04      VK4YB      0.475614      -28    VA7MM      11872 km     
11:02      VK4YB      0.475615      -33    VA7MM      11872 km     
10:54      VK4YB      0.475615      -26    VA7MM      11872 km

I should mention that the other VE7 stations are all operating from noisy suburbs near Vancouver ... clearly fine examples of what can be done on 630m under less than ideal operating conditions and by paying close attention to system optimization. Please don't let living in the city stop you from enjoying the mysteries and challenges that our latest ham band has to offer ... as mentioned earlier, there is still much to be learned about using this band at amateur radio power levels and small backyard antennas. How exciting is that!

Roger, VK4YB

I've been exchanging e-mails lately with Roger, VK4YB, in Queensland, Australia.

Roger is located about 30 miles from the ocean and has been the only VK signal that I have been able to hear on 630m WSPR mode. He seems to have the strongest signal out of Australia on 630m with his 90 watts and 120' tree supported wire vertical. John, VE7BDQ, has been heard twice down under with his modest station running at the allowable 5W EIRP limit, being reported in the fall of 2015 and again this spring. As well, John has heard Roger, the only signal from VK that either of us has copied.

I would like to be able to run some schedules with Roger in the fall, when transpacific paths should peak again. With that in mind, construction has begun on a new 630m transverter that will allow me to drive my present FET amplifier at full EIRP. Our schedules will utilize the JT9 weak signal mode, similar to JT65 but designed for the noisier LF and MF bands. It uses about 10% of the bandwidth that a JT65 signal requires, about 15Hz, and gains about 2db more sensitivity. A two-way QSO, under the best conditions, would take four minutes if all went well. A typical exchange of the required information, if initiated at my end, would look something like this:

                    VK4YB VE7SL
                    VE7SL VK4YB -20
                    R -18
                    RR 73
               73 73 (not really needed but indicates RR received)

The path from my end is difficult as I am on the east side of Mayne Island and in Roger's direction, about one mile from a 600' hill directly in line with VK. Any RF heading Roger's way will need to leave here at a fairly high angle, which is likely the case anyway considering the low and short (in terms of wavelength) inverted-L antenna.

The path profile from here to the open Pacific Ocean is shown below, with my end being on the right edge, just behind those two hills. The rest of the obstructions are on Saltspring Island and then Vancouver Island, before hitting open water.

VE7SL To VK4YB courtesy: Hey What's That Path Profiler

The most consistent west coast signal to reach own under is from Larry, W7IUV, in Washington state, operating experimentally as WH2XGP. Larry's path is a little more forgiving although his inland location certainly doesn't help. His first obstacle is about 10 miles away and about 2,000' higher. I would guess that his signal is well above that before reaching those mountains and the remaining higher Cascade peaks would not interfere.

W7IUV To VK4YB courtesy: Hey What's That Path Profiler

To VK4YB courtesy: Hey What's That Path Profiler

The path from John, VE7BDQ, already heard in VK, is also easier than from here. Not far from the water, John has a pretty clear shot across Georgia Strait, giving his signal lots of time to gain altitude and clear those pesky Vancouver Island peaks.

VE7BDQ To VK4YB courtesy: Hey What's That Path Profiler

VE7CNF's (Toby) path profile is similar to mine in that he is confronted very early with a hill to clear. Once over that his signal should be well above the mountains.

VE7CNF To VK4YB courtesy: Hey What's That Path Profiler

VA7MM's (Mark) path profile looks a little better than Toby's as there is a little more distance for his signal to gain altitude before passing over Vancouver Island. Markus was also able to detect VK4YB's WSPR signal earlier this spring and is looking forward to the fall tests with Roger.

VA7MM To VK4YB courtesy: Hey What's That Path Profiler

VE7CA's (Markus) path profile is probably the best of all of us on the west coast as he is located high up on the hills to the north of Vancouver along with an open shot to the ocean.

VE7CA To VK4YB courtesy: Hey What's That Path Profiler

I think my only advantage here is my quiet receiving location as it's going to take some brute-force to get over those nearby peaks. Like many of those operating from the suburbs, higher noise levels really take their toll on weak-signal reception and that will be the biggest obstacle for those operators in the city. Twenty years ago, this would not have been nearly such a problem!

VK4YB Path To Pacific courtesy: Hey What's That Path Profiler

Shown above is Roger's path to the Pacific and illustrates one of the reasons why he has the best signal into North America on MF! Although 30 miles from the ocean, there are no obstructions, yet ... coming soon is a 120' cell tower, directly in line with North America and less than 1000' from his antenna. Hopefully it won't cause any problems other than being a dreadful eyesore.

As the solar activity slowly abates (but not this week!), propagation on 630m will slowly get better and better ... hopefully along with increased levels of Canadians transmitting on the band, and lots of stations in the USA. It is hoped that our enthusiastic neighbours to the south aren't too far away from getting the band fairly soon. Better get those soldering irons warmed-up so you are all ready to go!