160 m SOTA activity day 2018

Several weeks ago, a number of regular SOTA activators started discussing options for what has become an annual event: a SOTA activation event held close to 1 April, with a couple of activities to be considered: AM mode and/or 160 m.

I have heard some SOTA and Parks activators making comments regarding the supposed difficulty in erecting an antenna for 80 m, so one would not expect those activators to consider 160 m operation.

I started to consider how my participation might occur this year. The chosen date was the Saturday of the Easter weekend, so options included getting away from home to somewhere a little more remote, staying at home to avoid the traffic and crowds and/or activating a local summit. In the days leading up to the weekend, I decided on the last option: stay at home and thus avoid the heavy long weekend traffic, but heading out to a local summit for the Saturday late afternoon activation event.

I considered a number of antenna options, but decided to build an inverted L for 160 m. I still had some of the DX Wire UL wire on hand for the main radiator wire. I visited a local electrical supply outlet and purchased some 1.5 mm2 single core cable and started the task of measuring and assembling the various wires. By Friday afternoon I had the components: 4 counterpoise wires, each about 12.5 m long, from the single core cable purchased. The cable was red, so should be easily seen and I settled on the heavier house wiring cable as it should sit on the ground reasonably well. The radiator wire was about 40 .2 m long and wound onto a SOTAbeams antenna winder together with 30 m or so of builder’s line. Also in the kit was a BNC to 2 x 4 mm binding post adapter.

31 March 2018

The 160 m antenna components plus all the usual SOTA and Parks gear was loaded into the vehicle after lunch on Saturday, together with my as yet unused 12 m and 18 m Spiderbeam telescopic poles. I had purchased the 12 m pole about 18 months earlier and had not yet put it to use. The 18 m pole was purchased second hand in late January 2017 but had not yet been used. I had built 2 carry “cases” for the 2 long poles, using appropriate sized poly pipe with a fixed cap at one end of the pipe and a screw cap at the other. The cases would provide some protection when in transit and when handling the poles, plus the case could be used as a base support for the pole, rather than strapping the pole in use direct to a support.

Mount Hooghly VK3/VT-049 698 m 2 points

I have visited this summit on several occasions, as it is the closest summit to home. The summit used to house a low to the ground fire spotting tower, with the platform only a couple of metres off the ground. However, vandals abused the building and its remains were eventually removed from the site. One end of the access road has become very overgrown, whilst the other end is now significantly narrowed due to regrowth from the sides of the track. Eucalypt plantation trees are surrounding the track on the western approach. The final track from the saddle just below the summit has some deep ruts from some of the local hoons tackling the track aggressively in wet conditions.

I left home at about 0520 Z and drove up the approach route. The final approach was slow, with the encroaching vegetation and then the ruts to negotiate. I parked in the area between the trig point and the small knoll on the western end of the summit.

Scouting around, I picked a bush of about 2 m height as the support for the 18 m pole case and started the setup. I pulled out the first section of the pole and used some double sided Velcro to hold the radiator wire to the pole near the junction of the top and next section of pole. I then ran out the radiator wire prior to raising the pole section by section. The 18 m pole is heavy! I ended up not using all sections of the pole, with the high point of the wire at around 13 m above ground. The far end of the wire was run out to the NE and the support line tied off to some scrub at about 2.5 m, leaving the end of the radiator at about 6 m off the ground. I then ran out the counterpoise wires and connected the wires to the adapter. A length of coax then ran to an antenna tune and then the IC-7000 with the power set at about 30 W. I had an antenna analyser with me, but took a simple approach and simply hit the tune button on the radio. The tuner found a match, so I started looking around the band.

The next task was to start up the tablet and VK port-a-log – I was to finally try electronic logging on a tablet in the field. This was the first time that I had actually used the the app, so it took a little extra time to start…..

First in the log was Helen VK3FOLK/p in The Nut State Reserve VKFF-1831. It was a tough contact with 40 m very noisy plus we were a little too close given there had been poor NVIS on 40 m throughout the day. I then worked Paul VK5PAS before checking ParksnPeaks and moving to 20 m. The tuner again found a solution and I soon had Bill VK4FW/p in VKFF-1681 in the log. Next was John VK6NU/p on VK6/SW-039 on 17 m SSB. A quick look at SOTAwatch lead me to 30 m, where I worked Chris DL4FO/p on DM/HE-570. I listened around the bands trying to hear and work some of the EU activators, but could not break through.

I returned to 40 m SSB and spotted myself. A string of chasers were worked, including Bernard VK2IB/3 and Warren VK3BYD/p, both on Mount Hotham VK3/VE-006, and Gerard VK2IO/p on Canoelands VK2/SY-002 in VKFF-0041. I later chased Marcus VK5WTF/p on Mount Gawler VK5/SE-013. After several more chasers were worked on 40 m and 80 m, it was time to add some extra layers due to the rapidly falling temperature.

I again spent some time searching for and attempting to work more of the EU activators, again without luck. Checking SOTAwatch, I saw John VK6NU/p again, this time on 20 m CW and made the contact. I again checked SOTAwatch and saw that Warren and Bernard had started on 160 m, plus Allen VK3ARH/p was now active from his summit. So I switched to 160 m and soon had a good signal from Allen, who was working John VK2YW in Wagga Wagga. When they finished, I sent my callsign and soon had my first S2S contact on 160 m CW in the log. Allen was on Blue Hill VK3/VG-010 in the Cobberas, giving me a new Chaser unique. I then dropped down the band to work Warren and Bernard on Mount Hotham. Three 160 m CW S2S contacts in the bag! Plus the summit was also qualified on both SSB and CW.

I briefly considered my options: to spot myself on 160 m or not? Or perhaps look for more EU stations? It was now almost 1930 local time and the sun was below the horizon, plus the temperature was about 11 degrees. I decided to shut down and pack up whilst I still had a little light left. As I was packing the antenna, I noticed the moon rising over the ridges – with a distinct pink hue induced by the smoke in the air from burns in the region. In the photo, you can make out the pole holder on the left, strapped to the bush. The pole had already been lowered. Not the best photo – taken with the ‘phone in low light!


Moon rise from Mt Hooghly

With all the gear in the vehicle, it was time to make my way back down the hill.

I would not normally use the 12 or 18 m poles for SOTA as they are heavy! But this was a “drive up” summit, so nothing needed to be carried any distance. I also need to consider options for supporting the poles at sites without convenient support structures. I was happy with the performance of the inverted L – I made contacts on all bands 160 to 17 m with only a few seconds for the tuner to match the antenna on each band change.

I also noticed that the Victorian mapping system shows a spot height near the summit of 698 m, but also shows two contours at 700 m, so will pass this information on to the Association Manager – it will mean an extra 2 points for the summit after the update goes through….

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