Monday, 4 April 2016

630m To Down Under

Today's Sun courtesy:

With the sun remaining reasonably quiet over the past several days, a sudden spike in the geomagnetic field on Saturday afternoon saw a number of trans-Pacific spots showing up on 630m WSPR mode.

In the predawn hours of Sunday morning, my own system decoded the VK3ELV WSPR beacon, located in south east Australia, 12,992 km from here. From an e-mail exchange, it seems that VK3ELV is using a 'drifting' IC706M2G on 10Mhz with a VK3XDK Transverter into an old HF AMP (2x 2SC2290) modified for 630m. This is running about 130-140 watts output. The antenna is an inverted L about 30 metres high and 1/4 wave long.


VK3ELV 630m
Further to my south, the WG2XGP WSPR beacon run by Larry, W7IUV in central Washington, was reported down under by two different VK's on Sunday morning as well ... VK4YB and VK2DDI, both some distance from VK3ELV.

It's interesting to note the time difference for these receptions, with Larry's reception being several hours earlier than my own (1304Z), close to my sunrise. As well, the 'spotlight' effect of propagation over such a vast distance is somewhat intriguing. I would have thought that if I should see any VK's on 630m, it would be the closer ones and not the further one, yet it was just the opposite.

Although VK3ELV's signal was right at the edge of WSPR decoding levels (-29db), it would only take a few more db to allow a two-way JT9 digital mode QSO to take place ... maybe something that will be possible in the coming years of solar minimum and much better LF/MF propagation. To be readable on CW would need an equivalent true power output increase of at least 16 times, requiring VK3ELV to run around 2,000 watts output!

Over the years I have seen ZL6QH a number of times on 2200m (QRSS CW mode) but this is my first reception of VK and, hopefully, not my last.

To keep up to date with overnight activities on 630m, visit the excellent site of KB5NJD. John posts a detailed daily summary of events. In addition, you will find some excellent resources to help you get involved in this part of the spectrum ... and remember, you don't need a big backyard or a big antenna to have fun on 630m.

1 comment:

woyse said...

Very nice write up Steve. Info like this will help to populate the band. The VKs have been doing well into NA lately. It has been fun to watch the "news" on John's daily 630m blog as you mentioned.

Keep the fun rollin'