Mt Stromlo activation 30th May 2014

WIth mild autumn weather continuing it seemed wasteful not to activate one of the 1 point summits that’s so conveniently nearby the Canberra city area.  I was able to get away from work earlier than usual and made it to a suitable car park on Mt Stromlo.

This time I walked over to the northern part of the mountain, which is readily accessed from the area near the trig point.  Just walk down the gravel road and back up to the northern part of the summit.  The dip is only 7-10m max, so the northern area is within the activation zone.  Up there you will find plenty of places to mount antennas and even a park bench seat to operate from.  However there is a mountain bike trail passing nearby so take care not to set yourself up near that trail.  Antennas across that trail would be a danger to anyone on a bike so have a good look around and plan your operation with that in mind.

The main reason for using that part of the summit for SOTA activations is to get away from a noise source causing interference, which I and others have experienced at Stromlo.  It has been assumed to be from power lines with either faulty or contaminated insulators and it produces s7-s8 noise on 7 and 14 MHz.  It can make reception of weak signals quite difficult and is the opposite of what you want and expect on a summit.

On arrival at the site I found I had left the connector base for the 20m vertical at home so I put up the linked dipole.  It has links for 10, 15, 17, 20, 30m inside the 40m full length. I used automotive type spade connectors for the link connections. Open a link and the dipole is shortened.  Multi band, but requires partial collapse of the telescopic pole to get close enough to the link points for 10m-20m.

I made 4 contacts with European CW ops on 20m, so qualified the summit within about 15 mins of turning the radio on, spotting myself and calling cq two or three times. This was with the 5w from the FT817.  Signal reports indicated the signal was low, 429 up to 539.

I wanted to try an idea I had for adding 12m to this antenna without adding another link.  A short length of antenna wire with a spade connector was added to the 10m point, making it possible to use 12m as well as the existing bands.  The SWR appeared to be ok though some fine tuning may improve it.

I used SMS to contact Matt VK1MA to see if he could give me a contact on 12m.  He was in the middle of a phone call to another ham, so it was quite ok to crank up the radio to 12m and add another contact to our 12m challenge logs.

After all that I went back to 20m and looked for more contacts into EU.  It all sounded rather dead by now, an hour after sunset, so I went to 40m and called on 7090.  One contact with big signal levels into the Coffs Harbour area.  S9 both ways.

There is some interest from US chasers who want to work VK on 20 or 17m.  This may result in a lunch time activation or two, just to see what is possible.  For 17m I will look at making my 20m vertical into a linked type for the vertical element and possibly just add some suitable radials for 17m.

While I was onsite, about 2 hours, I saw about 20 or 30 mountain bike riders arrive near my operating position and then ride off down the trail, their bike and helmet-mounted lights turning night into day.