SOTA – Mount McDonald 52 MHz activation

Mount McDonald VK1/AC-048 789 metrs ASL, Cotter Dam Catchment

Sunday 29 March 2015. I have two homebrew SOTA multi-band link dipoles, my spare lightweight antenna has a 6m link.  Yesterday I modified my primary antenna to include a 6m link with a center frequency of 51.150 MHz. I tested the antenna on 52.2 MHz using an analyser plus the radio combined with a SWR meter.  The SWR on 52.2 MHz is 1.3:1.  Also checked the 10 m link, all ok.  Today my plan is to test the 6m modified link on air with an activation of Mount McDonald on 52.2 MHz USB.  Mount McDonald is 20 km south-west of the Canberra GPO.

Mount McDonald summit walk starts from Brindabella Road, the car park is a short drive from the Cotter Campground.

Mount McDonald ascent: The ascent is 205 metres over 2.8 km taking 40 minutes.

SOTA equipment: FT-817ND QRP, battery LiFePO4 4S 4.2 AH, antenna homebrew half-wave link dipole and a 7 metre telescopic fiberglass squid pole.

SOTA half-wave link dipole. Picture of my SOTA half-wave antenna with links for 6/10/20/40 metres.  The center plate 10 mm hole mounts over the squid pole seating 300 mm below the top of the pole.   You are not restricted to using a pole support, combine the center plate with a length of rope over a tree branch or some other support.

I will post construction details of my link dipole soon. For now I have included 4 pictures showing design.

VK1NAM SOTA link dipole 6/10/20/40 metres

VK1NAM SOTA link dipole 6/10/20/40 metres


link insulator – 40 mm length of 6mm fiberglass rod

TET-Emtron molded UV resistant plastic center plate.

center plate - SO239

TET-Emtron center plate – predrilled for the SO-239 flange

Factor to your calculations 100 mm of wire on the center plate.

center plate - rear of the SO239

center plate – rear view of the SO-239 flange

OzTopo map using Garmin BaseCamp – Route to Mount McDonald from Brindabella Road

Mt McDonald GPS track log

Mount McDonald GPS track log

Track profile

Mt McDonald track profile

Mount McDonald track profile

Start of the gravel walking track from Brindabella Road.  I didn’t see a single sole for the entire activation.

Mt McDonald walk info

Mount McDonald walk info.  Vegetation around the catchment was destroyed in the 2003 fires

Locked gate – Authorised vehicles only and no dogs.

Catchment area - no dogs

Water catchment area – no dogs!

Turn right on to Mt McDonald Road

Turn right on to Mount McDonald Road

Lookout 700 metres and 2 km to the summit

Lookout 700 metres 2 km to the summit

View south along Bullen Range VK1/AC-033

View south along the Murrumbidgee River and Bullen Range VK1/AC-033

view east to Canberra through the smoke haze

view east to Canberra through the smoke haze

Fuel reduction burn on Tidbinbilla Ridge near Camels Hump

Fuel reduction burn on Tidbinbilla Ridge near Camels Hump

Burn off

close up

Mt McDonald Trig

Mount McDonald Trig station supporting the squid pole

Opened the activation at 22:25 UTC (09:25 am local) on 6m 52.2 MHz USB to work Matt VK1MA, Andrew VK2MWP, Ian VK1DI, Steve VK2NSS, Paul VK1ATP and Nick VK1NK.   Post UTC day change on 6m; Ian VK1DI, Al VK1RX and Andrew VK2UH.  Eight unique chasers on 6m terrific.  😉

On 20m 14.310 MHz USB I was very surprised with the band open for short skip to VK3 working Ron VK3AFW, VK2 working Less VK2CPC, Paul VK2KTT and Adam VK2YK.  Mike VK6MB called in for a long haul chase some 3000 km from Western Australia.  🙂

On 40m I worked a range of VK5 National Park and Conservation Park activators.  First chaser on 40m was Amanda VK3FQSO followed by Jenny VK5JEN/M, Paul VK5PAS/P at Leven Beach CP VKFF-814, Adrian VK5FANA, Peter VK3PF QRP, Fred VK3DAC, Gerard VK2IO/M, Peter VK3TKK, David VK5NQP/P at White Dam CP, Ken VK3UH, Andrew VK5KET/P at Penola CP VKFF-803, David VK5HDW/P at Beachport CP VKFF-791.

Post UTC day change.  On 40m, Andy VK5AKH/P at Coorong NP VKFF-115, Matt VK1MA, Lee VK2LEE, Gerard VK2IO, Brenton VK2DDS, Andrew VK2UH, Peter VK3PF, Tom VK5FTRV/P at Gower CP VKFF-798, Chris VK4FR/5 at Mount Taylor CP, Ray VK3YAR/M and John VK2YW.

Summit to Summit contacts (S2S).  Rik VK3EQ on Mt Buller VK3/VE-008, Tony VK3CAT on High Cone VK3/VE-240 VKFF-619 and Glenn VK3YY/P on Federation Range VK3/VN-029 VKFF-556.    Thanks Rik, Tony and Glenn for 27 point towards the S2S log.

Conservation and National Parks chased.  Beachport CP, Gower CP, Leven Beach CP, Mount Taylor CP, Penola CP, White Dam CP, Alpine NP, Coorong NP,and Yarra Ranges NP.

Thanks activator and chasers for an excellent activation at Mount McDonald   🙂

VK1NAM SOTA shack on Mt McDonald

VK1NAM SOTA shack on Mount McDonald VK1/AC-048

Views from the Lookout

Cotter Dam

view west overlooking the Cotter Dam

Cotter Dam

Cotter Dam view north-west

6 thoughts on “SOTA – Mount McDonald 52 MHz activation

  1. I’m a bit late to the party Andrew, but it looks and sounds like it was a great day for a radio outing! Good weather and good contacts. Cheers! 73, Mike, KEØGZT

  2. Pingback: SOTA – VK1 SOTA DX Mount McDonald | Get out of the Radio Shack and Live Life

  3. Pingback: SOTA – 40m link Inverted V dipole antenna upgrade for 3.5 MHz | Get out of the Radio Shack and Live Life

  4. Hi Andrew, Good set up for 6m ..sorry I didnt manage to catch you as I was away. I need to re-do my linked dipole as well and add 6m – another job :). All the best – John 2YW

  5. Hi Andrew
    I like the antenna and what a great effort on 6 metres. The Tet-Emtron gear from Mark is very good and plenty of space on the winders.
    John D

    • Hi John,
      I met Mark at Wyong, great guy. We had a good chat about SOTA, I gave him a plug from the SOTA stand. I received lots of interest in the link HF dipole and winders.
      73, Andrew

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