Variable HF conditions produce surprises

An opportunity for a short activation presented itself this afternoon when I left work. So while the car cooled down a bit from the day’s 30C heating I composed an alert for VK1/AC-041 Isaac’s Ridge. 7pm > 0800UTC > minus 11 hours for the sotagoat time error = 2100 yesterday UTC.

On site and having erected the antenna with all links closed, checked 40m. Very little activity. Ok, self spot via vk-port-a-log with the Lenovo android tablet connected to the iphone via wifi, wait till sotawatch receives it, then run a few cqs. On the third cq an answer from John ZL1BYZ, s9. After that more cqs, and a strong signal starts up 1 khz lower in the band. Went down to give him a call and log contact #2. After that no replies for a while so I wandered up to 10 mhz and looked for activity. V73NS was running a pileup of sorts, 10.118 or so, I disconnected the 30m links and called him when nobody else seemed to. QRZ? Etc and eventually extracted a report of 119 from him (barely detectable and unreadable, so how he cpied a report I don’t know, but he sent R and TU so that was me dealt with). So back down the band a bit, 10.113, QRL? Then a few cqs. The 703 has a memory keyer function, kit key 2 and it sends the canned cq again. During that you can drink water, check 2m fm, make sure the log is ready for a caller.

To my surprise I was being called by ON4VT, not strong signals but good enough. Then an EA who I didn’t recognise (and my log is in the car) but was very pleased to work. Then VK7CW much weaker than the Europeans. Very long skip conditions.

After a while, back on 40m, ssb this time. A few callers including ZL2ATH and finally Gerard VK2IO, who said my signal emerged from below the noise and within seconds was s9. Sporadic E most likely… distance from Canberra to Sydney is only about 250 km so some high angle reflection is essential.

11 contacts over 50 minutes, some not easy, but it shows that if you shop around and use the bands and modes that will most likely produce contacts, they often do.

Don’t really like Isaacs Ridge, some noisy gear up there and our local club has a repeater and a beacon on 2m. So the HT was probably flattened by that even if it survived the other RF up there.

Closing down right on sunset I was able to get back to the car in 20 minutes with a bit of light left to see the thistles and avoid the kangaroos. Ran into a spider web at one point, again not my favourite thing, but no big deal.

Rig: IC703, 10w output, has dual mech filters (W4RT) and home made linked dipole on a 7m telescopic pole, feedline RG58.

Andrew VK1DA/VK2UH


Hi Andrew, the 2m FM repeater on Isaacs Ridge is currently down (the 2m RF connection is being used to keep the 2m D-Star repeaters happy on the rare instances they use it). The repeater site is almost 2km to the north of the usual activation site at the southern end of the hill, so I would expect that the beacon (about 10W IIRC and 2MHz below the 2m calling frequency) should have minimal impact on 2m users there. I think that the main impact on 2m would be from VHF highband transmitters on the other commercial towers on the southern end of the hill.


hi Matt,

I’m surprised Isaacs ridge is that big that the beacon can be 2km away from the trig. But anyway as you say, it is likely the other RF there is the problem with HTs. I have always noticed problems there on 2m fm. I need to build one of the filters like the one Dale published in AR, to just reduce the level of the nearby QRM, probably high band vhf commercial services. I have a suitable enclosure complete with connectors, so should get it done.


Andrew VK1DA/2uh

The next day I activated Livingstone Hill, this time I took the makings of a quarter wave vertical for 30m. After building it and trying it with the 3 radials normally used for 20m, I found it returning very low SWR readings and decided to give it a go. Not particularly successful. Conditions just didn’t support my aspirations.
On 20m I spotted myself and then found several stations calling blind, but they were not hearing me. On SSB I worked ZL but no more distant stations.

40m was the best of the lot, despite high QRN. Made 4 contacts on cw and none on SSB.

A few 2m fm contacts back into Canberra, VK1AD on Mt Ainslie for a S2S and Matt VK1MA at home. Wade VK1FWBD was listening for me without success. Thanks for trying anyway.

Andrew VK1DA in the field, VK2UH at home

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Hi Andrew - actually 1.8km from our repeaters to the southermost towers, but yes it is a long ridge. Good idea re the filters, but yet another thing to have to carry up there!


The filter built by Dale is about 50mm x 20 x 20. Light as. Just screws onto the HT and the antenna connects onto the filter.

Tonight on Mt Ainslie, conditions on 40m were not too good when i first was on air.

Worked a few contacts into vk4,5 and ZL on 40m. 1000km+. Sigs from closer stations were very weak.

Then moved to 80m where there was no noise, s1 on the meter, lovely strong signals from vk2/3/4/7 on ssb. Then moved to cw end and had a contact with Gerard vk2io, much stronger than on 40m a bit earlier. A 250km path. But the vk4s on 40 were s9. And bill 4FW was s9 on 80m and returning s7 reports on my 10w.

Finally returned to 40m cw to work john AC4CA in Texas. S9+10 on peaks and returning s8 report. Heard Ellen W1YL/7 again too but only s9 not quite as strong as the texan. Sunspot lows are always great for 40m dx. Even more thrilling to make those contacts with 10w. Its a long way across the pacific.

Tonight i used the zs6bkw doublet fed with tv ribbon.


While out doing a wwff activation this past weekend I worked my first VK station on 40m running 5w. I was in Michigan. Greyline (my morning). I am still flabbergasted.



What UTC time was that contact? I have not worked a NA S2S contact yet, got close but never made it. I’m keen to try. We lose daylight saving this weekend so my after work activations will be less frequent. That site I was at yesterday is a driveup making exits after dark fairly safe so its an option. Sunset is currently 0800 or so, and in the next 3 months that will move steadily to about 0650 at the winter solstice. I hear US stations from about 0600 onwards even now.

I can also bring a few extra watts if that will help.

Andrew VK1DA/VK2UH

Also, Mt Ainslie is in a nature reserve so if you are into WWFF it would give you vkff-0850.

It was just shy of 1300 UTC. Under normal circumstances I am not usually on a summit by that time, but if I am camping in a wwff location I like to get on the air early in the morning for variety (and apparently, talking to people on the other side of the earth!).

That said: two weekends hence (so the weekend of the 7th and 8th) I may be on a summit overnight. Plans are still fluid, but I would be in an extremely RFI quiet location. If you (or anyone else) wants to try an experiment, I am game. I’ll be backpacking so I’ll be limited to 10W on the KX2, but I theoretically can pack a 40m vertical.

As for wwff refs: I don’t chase them too much, mostly using wwff as more a sport to tide me over between SOTA trips :smile: That said, sure would be cool to add a vkff ref to the log.


Its very early for you i guess around 5am and would be 11 pm here. Lets stay in touch. I’m assuming this was a cw contact, right?

It was cw, yes. This is the time of year when it’s impossible to keep track of what time it is anywhere, but I can say 1300z was 9am local MI time last weekend. That would be 8am on the summit on which I may be camping (W0M/SF-038) so not very early at all.

For no good reason I calculated for the west coast (8 hours off UTC) then wrote east. Oops. And yes the DST changeover occurs this weekend in southern vk but different weekends everywhere else.

So to coincide with the sunrise grey line at your end an 11pm activation time is needed here. On 7th April we have a QRP Hours contest on 80m ending at 10pm local. Anyone out for that could look on 40m after that event. Nick/Wal vk2wp might be up for that too.

Happy to try if you let me know in advance.


Andrew VK1DA/VK2UH

Confitions were promising this morning with John ZL1BYD fair copy on 21, 14, and18 MHz. Later it was a struggle to copy the VK6 activators.
Zip from Mike or Ed. Missed 2 VK summits due to one activator being a chatty type and another seemingly too shy to call CQ often.

It also helps if your report is 33 to give the callers report at least 3 to 5 timrs slowly to try and get a qsb peak.

Hi Ron - S7+ atmospheric noise at this end, so even if you had heard me, I probably wouldn’t have heard you!

Tried both horizontal and vertical antennas on 20m and the horizotal on 40m - just contacts around Europe, no DX.

73 Ed.

No Europeans made the log today, but I could hear Mike very weak and called him but no luck, nothing from you Ed. Even CW was quiet with only one CW contact in the log. Took Luke VK6ZLB on his first Sota Activation and glad to report he easily got his points.

I was using AX6NU for ANZAC DAY and its not a bad prefix for CW. Ended up with 17 in the Log and an S2S with Lewis VK6LDX just down the road at Mt.Cooke.

Beautiful day out in the WA sunshine.

John AX6NU/P

Hi John,

I believe Mike was running 100w and the big Antron A99, whereas I was somewhat more lightweight on the antenna side and only 20w output.

I saw a very high base noise level. I am guessing that was atmospheric, did you see a high noise level in AX ?

73 Ed.


Hi Ed,

I was running 50 watts, however, the 40m band was much harder today. Nevertheless, ZL finished in my log but no VK heard on the band. I heard who I’m 99% certain was VK6LDX on VK6/SW-031 calling me on 40m but he was just too weak to work. Last week, he would have made the trip.

20m was not too good, however, ZL and VK made my log.

The 5c temperature and cold wind was a shock to the system, it would appear winter is back.

73 Mike