Tag Archives: 1296

VHF/UHF Field day January 2014

I set up my usual station on Mt Ginini QF44JL for this event.

On 50 MHz, a TS670 and a HL66V amplifier producing 60w to a 3 el cushcraft yagi on a 4m mast.

On 144 MHz, the IC910H 100w to an 8 el yagi at 6m agl.  On 432 MHz the IC910H 75w to a 16 el yagi at 4.5m agl with an icom mast head preamp 1.5m from the feedpoint.

On 1296 Mhz I had unfortunately not packed the pair of 18el yagis normally used.  As a token antenna to make some local contacts, I connected a 2m quarter wave vertical with about 3m of RG58 coax and laid that horizontally on the roof of the tent, bisecting the side and centre aluminium stressors that are part of the roof structure of my old Coleman tent.  This “antenna” gave me some local contacts on 1296 and with effort, a contact with vk2smc near Nimmitabel.

On Saturday I found conditions ordinary with no unusual contacts made.  On Sunday morning at 5AM local time I checked the usual beacons from Sydney, Mt Anakie in VK3, Mildura in VK3 and the Gippsland beacon, on both 144 and 432 where possible.  With the very calm conditions overnight I wondered if I would hear any beacons from further afield and checked the Mt Gambier beacon VK5RSE on 144.550 and the Adelaide beacon VK5VF on 144.450.  Both beacons were received at good strength, and during the following 5 hours both beacons remained audible, the Adelaide beacon being the strongest signal most of the time until it faded around 9AM, the Mt Gambier signal remaining audible but weak for a little longer. My log notes that VK5RSE was still audible at 2305 UTC, or 10AM local time. At that stage the Adelaide signal had vanished.  With these beacon signals received so well, how about making some contacts into those areas?

I then worked Bill VK5ACY at 1922 UTC (6:22 local) vk5LA at 1939, vk5AKK at 2006, VK5PO at 2008, VK5DK at 2109, all on 144MHz.  I also worked Vk5AKK on 432.

Much later at 2150 I was called by VK5PJ on 2m while beaming to Sydney direction (NE) and made a good contact with Peter on that band, followed by working him again on 432 MHz, still with the beams NE.  Turning the beams around to the west produced signal levels of S9+20 (indicated) which is a rare event on 70cm dx.  Peter asked whether I had 23cm and I told him that regrettably my real antennas were at home and all I had was a temporary lashup to make local contacts.  He was keen to try it given the unusually good propagation we had on 70cm.  We tried 23cm first with Peter running a series of dots, so I tuned for that signal on the Sub receiver on the IC910 and could tell him “yes I do hear that, I will send the same to you”…  and the outcome was a good 5 x 1 contact on SSB.

Back on our “liaison frequency” 432.160 where signals were still s9+ I told Peter what the antenna was.  “It’s a 2m quarter wave lying on the roof of my tent”.  He asked for a photo…I took the following photo immediately while still sitting at the desk talking with him.

Note the precise calibration of the angles.

horizontal 9/4 wave antenna
horizontal 9/4 wave antenna

Here is what it looked like from the outside.

Tent roof antenna
Tent roof antenna. Note the centre boom and the supporting spines all aluminium. the antenna received best signal on 1296 when at 45 degrees to those tent supports.  Adelaide is close to the direction of the centre boom.

I then asked him to run the beeper again so I could try to optimise the orientation or location of the antenna.  I tried vertical and horizontal polarisation in various orientations.  Eventually I returned the antenna to its original position where by good luck, the signal was best.  You would not read about it.

Later at 2223 I was encouraged to give this antenna a try working VK3ER where Peter VK3QI was keen to make the contact.  And yes it did work, even on ssb.  In the past we have made contacts with my real antennas but sometimes it has been quite difficult, cw-only.  Clearly propagation was unusually good between us.

A later attempt to hear or work Gordon VK3EJ at Cobram was unsuccessful.  Whatever atmospheric effect was allowing these longer distant signals to reach Mt Ginini was not active for the shorter distance to Cobram.

This is where the 1296 yagis would normally go… just below the 70cm yagi on the mast.

2m and 70cm antennas.
2m and 70cm antennas.

Summary: 145 or so contacts, some ordinary and a small number of extraordinary contacts, coinciding with very hot daytime weather and a calm morning.

Once again the beacons were a great indicator of the possibilities ahead.

As my brother Chris VK2DO pointed out, it looks like the many tickets purchased in the “field day lottery” over the past 20 years have finally paid off and I have certainly been rewarded with some great fortune this time.  If only I had my real antennas for 1296, and how about the higher bands?  Will never know, can only continue to take tickets in the lottery and hope it doesn’t take another 20 years to produce results.