Friday, 16 September 2016

First VK-VE 630m Contact!


Shortly before sunrise yesterday morning, VK4YB (Roger) and I were able to work each other on 630m ... 475.300 kHz to be exact!

This is the first-ever QSO between North America and Australia on the relatively new 630m MF band. As well, at 11,802km, it presently represents the furthest two-way contact on this band, worldwide ... but I don't expect this record will last very long once the U.S. gets the band as I believe Roger's fine station is very capable of reaching much further afield.

Our contact on JT9, the WSPR QSO mode, was made at 1319Z, about 30 minutes before my local sunrise with the sky surprisingly bright. Blog readers will know that Roger and I have been carefully watching the pre-dawn Trans-Pacific propagation path for the last week. I have been checking-in with him via the ON4KST LF/MF chat page every morning at around 0345 local time at which point a decision is made ... "get out of bed and head for the shack" or "go back to sleep". Each morning's (or in Roger's case, each evening's) propagation quality is assigned a code number by Roger, based upon what he has been hearing during the early evening hours ... a '6' or below is 'sleep-time', a '7' is a 'you decide' while an '8' or above is 'get your butt moving'.

Yesterday, Roger issued a 'code 7' but as I joked with him later, I think he tricked me as it seemed more like a '6.5' from this end! Trans-Pacific conditions were very good about 500 miles to my south but seemed to drop-off quickly much further to the north. I also need to get over a significant obstruction immediately to the SW of me and in line with Roger. That's me directly at the base of the hill on the right while the remaining peaks are on nearby Saltspring Island and then Vancouver Island before reaching the open Pacific.


I believe this requires some enhancement of high-angle arrival (and departure) which often occurs around dawn due to a short period of ionospheric 'tilting'. This is often noted by topband operators near their local sunrise, who regularly observe stronger signals on low (cloud-warming) dipoles than they do on their normal large (low-angle) verticals or beverage antennas.

We enjoyed significantly stronger conditions a week ago, but unlike Thursday when I could run at full 5W EIRP, I was only able to generate a little less than 1W EIRP at the time. So far, this week, conditions have been improving steadily each day, from a 'code 3' to a 'code 7'. Hopefully they will continue to improve and we can do it all over again sometime soon.

With my new antenna / transverter / amplifier relay control box working nicely, it seems that Roger and I can now fully take advantage of TP propagation from 'mediocre' to 'excellent' but we have yet to see just how good it can get.

Roger's signal is at +1100Hz
As noted on the screen grabs, both of us were operating near the limits of JT9 detection and we have both seen each other's signal several db stronger on previous mornings. For a two-way CW QSO to take place (a possible new goal), we will need to see an improvement of at least 10db ... probably something that the propagation gods will eventually deliver. Hopefully we will be ready for that should it materialize, providing I can continue to crawl out of bed in the ever-lengthening fall darkness.

It is hoped that our contact will inspire new interest among amateurs worldwide and particularly in North America. If you are planning a station, it seems that the main mode of two-way communications will be CW or JT9 ... a simple transverter would allow both modes as well as the use of the WSPR beacon mode. More information may be found here as well as in earlier 630m blogs.

See also:


Daniele Caccia said...

Congratulation Steve !!!

73 + 51 de Daniele from ITALY

SWL I55387FI

visit my blog:

Matt said...

Awesome job. Very inspiring.
de VE6JI

Knight Ao said...

Congrats, Steve!

de Yas JA8SCD/1

Steve McDonald said...

Thank you dr Yas san! I hope we can also QSO sometime on 630m JT9 mode!

Steve 73