First Australian SOTA and VKFF DMR contact?

After weeks of poor weather in Queensland, Saturday 10th November dawned bright, sunny and hot. This would be the perfect day to head for the hills and make a DMR contact, in simplex, on Talk Group 99 in Time Slot 1.

At first, my plan was to climb to the summit of Mt Beerwah (VK4/SE-057) but on reading a few blogs about the climb and what it entailed, I decided that discretion would certainly be the better part of valour on my part as I am not as young as I’d like to be. Much of the way up is undertaken on all fours, so the bloggers said; I didn’t want to chance becoming a helicopter Medivac casualty. Moving about on all fours isn’t advisable especially if you have gear that includes a rather long and unwieldy ‘squid pole’ to contend with.

So I set my sights a little further up the Sunshine Coast and settled on Mt Coolum (VK4/SE-114). And to make things even better, it falls within the Mt Coolum National Park (VKFF-0344).

My gear for this activation was my Elecraft KX1 (with six internal AA cells) and 24 ft long wire antenna with two counter-poises of 16ft and 32ft respectively. For seating arrangements I took along my Helinox Chair One.

Mt Coolum is the second largest solid rock mountain in Australia; the largest is Uluru (previously known as Ayers Rock) in the Northern Territory. This fact alone made it fitting that I should climb it as I had visited Uluru in July.

The way up to the summit is very steep but the path is excellent, consisting of suitably arranged rocks that act as steps. It is a very popular outdoor venue with the locals and as a result the way up and down is very busy.

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The was a constant stream of people making their way to the summit.

As soon as I arrived at the top I put out a call to Greg, VK4MHC, on DMR simplex with my CS750 hand held radio. He replied and sounded as if he were a few feet away, so strong and clear was the audio. And considering he happened to be at a local resort some 2km away, the quality of the signal was nothing less than astounding.

The simplex calling frequency in Australia is 439.200 MHz.

This I believe is the first time DMR has been used as a mode for SOTA and WWFF in Australia. (Our local VKFF representative in VK4 later told me after I had submitted my log that he was unable to process the DMR QSO as the system wouldn’t accept a Digital Voice call even though it’s listed as an accepted mode. He has progressed the issue further up the line, something that tells me it hasn’t been encountered before.)

We then proceeded to talk on 2m and 70cm FM; I used my Yaesu FT-70D and he used his Yaesu FT-818.

I then looked for a suitable spot out of the way of curious onlookers to set up my HF station. That spot turned out to be right in the middle of a thicket of sharp bushes that I cleared just enough for the chair.

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Keeping out of the sun was the name of the game.

Once my gear was in place, I settled down into my chair and uploaded a spot to SOTA Spotter. Who said the bands were dead? Here’s the list of the stations I worked using only 2W.

VK4JAZ 09/11/2018 22:39 VK4/SE-114 433MHz DV VK4MHC. (First DMR call in VK?)
VK4JAZ 09/11/2018 22:43 VK4/SE-114 144MHz FM VK4MHC
VK4JAZ 09/11/2018 22:44 VK4/SE-114 433MHz FM VK4MHC
VK4JAZ 09/11/2018 23:26 VK4/SE-114 14MHz CW VK7CW
VK4JAZ 09/11/2018 23:30 VK4/SE-114 14MHz CW VK1MCW
VK4JAZ 09/11/2018 23:35 VK4/SE-114 14MHz CW VK3CAT/P
VK4JAZ 09/11/2018 23:37 VK4/SE-114 14MHz CW VK3ARH
VK4JAZ 09/11/2018 23:40 VK4/SE-114 14MHz CW VK3IL/P
VK4JAZ 09/11/2018 23:43 VK4/SE-114 14MHz CW ZL3GA
VK4JAZ 09/11/2018 23:53 VK4/SE-114 7MHz CW VK2IO/P

In addition, VK3CAT, VK3ARH and VK3IL were also summit activations.

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At leas the view was good amongst the prickly shrubs.

 

 

 

 

 

 

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Testing the miniHFPA2 with the Elecraft KX1

I received a query from a reader yesterday regarding tuning up an antenna using the internal ATU in his Elecraft KX2 if it were connected up to the miniHFPA2 amplifier. The reason he wanted to know about this was because he was considering ordering one for use with his Elecraft KX2.

He wanted to know if it is it possible to run an antenna such as a doublet, by tuning the antenna using the KX2’s internal tuner with the amp in bypass mode, then switching the toggle switch on the amp to put it inline. He said that it appeared to him that this procedure would not work because the amp, once in line, would probably change the SWR of the antenna.

I decided to conduct a test to find out if this would in fact be the case. This is what I found:

I carried out the test in two parts:
Firstly, with the KX1 (powered by a 12V supply voltage) connected to a PWR/SWR meter and 50 Ohm dummy load.

On keying down, the PWR/SWR meter read the following: output 3.5W with SWR of 1.0:1

A straight through test with the signal going to the dummy load.Secondly, connected up the miniHFPA2 directly to the KX1, and the Pwr/SWR meter and dummy load.
With the Amp in bypass mode, the reading was 3W output and 1.0:1 SWR.

The only difference now is that the amp has been connected up but left in bypass mode.

With the Amp switched on and placed inline, the reading was 18W output with SWR 1.0:1.

With the amp in action, the SWR remained 1.0:1

Note: the lower than expected power output with the amp inline was due to the fact that the amp is set up for an input of 5W. My KX1 can only supply it with 3W, so the final output of the amp will be lower too. With 5W in, as is the case when connected up to my Yaesu FT-817, it outputs 30W.

Trends in Amateur Radio

It’s always been accepted that one of the attractions of amateur radio was that it involved the building of kits; if you needed (or wanted) a better or more specific transmitter, receiver or transceiver but couldn’t afford to purchase one from your local retailer, you bought one in kit form and built it yourself.
Kits were ordered over the phone and posted to you. Some were better than others but all had potential risks involved, such as the odd missing component.

The Elecraft KX1 kit came professionally packed with a great instruction manual.

This kit from Virgil Stamps at http://www.hfprojects.com is a good example of a well-produced kit that involves soldering all the components into place in the PCB.

And it wasn’t only on the electronics front that you could heat up your soldering iron and get busy; making a suitable antenna was also a huge part of the hobby.

My homebrew 6m dipole strung up and ready for action.

Baluns are also popular construction projects with homebrewers.

I wound the entire length of coax on a piece of PVC piping I had in my workshop.

Of course, you didn’t have to stick with kits if you needed to construct a radio; you could always build one from scratch with components you happened to have in your proverbial junk box.

I built this regenerative receiver using what I happened to have on hand at the time.

Test equipment is also easy to build from kits.

QRPometer on the left, Hendricks dummy load/power meter on the right.

I have noticed a trend beginning to appear in the world of amateur radio, and that’s a swing away from ‘melting solder’. I first noticed this with the advent of the Elecraft KX3 a few years ago. For the first time this world leader in kit production began marketing a rig that only required mechanical construction; all the electronics came pre-manufactured and only needed slotting into place in the enclosure, which needed first to be put together by the ham. This was due to the high number of surface mount components present.

And now Virgil Stamps, proprietor of the beautifully designed and manufactured HF linear amplifier that is aimed at the SOTA and WWFF fraternity (http://hfprojects.com/) has gone this route with the launching of his latest offering, the HFPacker Amp MiniHFPA2. By all accounts it looks like this new trend in amateur radio is here to stay, but as long as it helps get more people on air, that’s sure to be a good thing.

QRP Hours contest

Sunday 22nd October was a good day for QRP in VK-Land. And even thougth HF conditions haven’t been good at all (especially according to some), I had success and a lot of fun by taking part in this short contest run by the CW Operators’ QRP Club Inc.

This year the contest was restricted to the 40m band and consisted of two sections: the first hour CW and the second Phone. I took part in the CW section only.

The rig I used was my trust Elecraft KX1, this time with 12v gel cell power as I didn’t have to worry about weight: I was to operate from the back deck of my home. The antenna was the Buddistick that I attached to the hand railing of the deck by means of my new Buddistick G-clamp. My key was the Pico Paddle. Power output was 3W.

My set up for the contest. All ready to go.

Tuning up the antenna on 40m was not easy. I couldn’t get a match at all with my Hendricks BLT Tuner, so I hauled out my LDG auto tuner, which gave me a 1.9:1 reading, which was the best I got. QRP is all about compromise, so I went with that.

The Buddistick mounted to the railing with my new G-Clamp.

I do think that the proximity of metal guttering didn’t help, but I had to make do with the situation I found myself in. At least there was some good height, facing south – which would be good for VK1 and VK2 contacts.

Nice height even though I needed to angle the whip.

Noise levels were high on the band but nevertheless, I was able to work VK2IG, VJ2GAZ, VK2FGBR, VK1DA, VK2JDR and VK2IO.

Next time I’ll try a long wire antenna.

Activating Mt Cotton VK4/SE-115

This was one summit I have wanted to activate for quite some time, partly due its proximity and partly due to the excellent Sirromet Winery nearby. So when Sunday 30 April dawned with beautiful clear skies, I knew it was time. My wife decided this would also make an excellent day out.

The drive to the base of the summit took about 40 minutes. We parked at the bottom in a designated car park and headed for the gate that heralded the beginning of the path up.

This is the beginning of the path up to the summit.

Fortunately the path up is sealed, which made walking up easier, even though it was rather steep at times.

It took us 22 minutes to walk up to the summit.

Once at the top it was simply a matter of seeking out the best operating position. This was important as there are a couple of communication towers there and I didn’t want interference.

The going was tough at times.

I found a suitable spot among a pile of rocks, so I erected the long wire antenna on my squid pole, and connected it up to my Elecraft KX1. It tuned up beautifully on 20m and 40m. For power I use six internal AA 1.5v batteries that give me between 1 and 2 watts output to play with.

It was quite comfortable, really.

I put out my first call on 20m and within seconds was answered by VK3CAT in Victoria. Not bad for 2 watts. I then switched to 40m (only 1 watt) and worked VK2NP, VK2BJT and VK4TJ.

I find the Pico Paddle a wonderful device to use with the KX1. It is magnetically held in place on the tin plate on my home brewed QSO board.

That was sufficient for the activation to count, so it was time to pack up and head off down and to lunch at Sirromet.

Reverse Polarity Protection

As the Yaesu FT-817 doesn’t have any reverse polarity protection or an in-line fuse, I decided to build myself one seeing I do a lot of portable work on summits or in parks.
Diodes work fine but they do incur quite high losses in eventual output power, so with only 5W max available, this isn’t desirable.
The answer lies with the P channel MOSFET (FQP27PO6)
A quick search on line turned up this schematic.

Only one component!

This is quite a simple affair: when the battery is connected up correctly, the MOSFET is turned on allowing current to flow. When connected up incorrectly, it turns off.

It works thus: when the gate to source voltage is around -4V or less, it turns on. So if the battery is a 12V gel cell (as in my case), the voltage through the MOSFET  = 12V Р1V loss (due to the parasitic body diode) which equals 11V with respect to ground.The voltage at the gate is 0V as it is connected to ground. This means that Vgs = 0V Р11V = -11V. This is less than -4V so it turns on.

If the battery is connected up incorrectly, then we have Vgs = 0V –11V = 11V. so the devise turns off.

I mounted the MOSFET on a piece of vero board and used an ice cream stick as strain relief. I also included an in-line quick blow 5A fuse in the positive line.

All the components before final assembly.

Once the heat shrink had been slipped over the component, I heated it up with a hairdryer to achieve a nice, tight finish.

While I was at it I built another one for my Elecraft KX1.

Now it was time to test it.

 

All working as expected with the battery connected up correctly.

Now to switch polarity.

No voltage with reversed polarity.

Activating Mt Warning, VK2/NR-001

January 11, 2017 had hardly got going when my son Garrett, his partner Vicky and I set out to activate Mt Warning, an ancient volcano that is said to be over 20 million years old. For this expedition, we hired accommodation in Byron Bay as this would cut down travelling time to the mountain. You see, we wanted to watch the sun rise from the summit.

Mt Warning as seen from Byron Bay.

Mt Warning as seen from Byron Bay.

We packed the car and headed for the base of the mountain at 2.45 am, arriving there at 4.11 am. I was a little surprised to see that we weren’t the only ones with that idea; there were around ten cars parked in the car park already!

An information board advised us that the hike would take between 4 and 6 hours to cover the 9 km track.

We also noticed that right from the start the going was uphill. I could feel this was going to be a most challenging activation. What was beginning to concern me was that I might have bitten off more than I could chew. I mean, Garrett is a professional sportsman and Vicky is an ultra-marathon and Iron Man competitor while I am a newly retired ‘senior’. Was I in the right company or what? At least there were four helicopter landing platforms, which gave some sort of comfort.

The first of four helicopter landing platforms.

The first of four helicopter landing platforms.

Sunrise was around 6 am, but we weren’t at the summit to view it. However, we were close enough and boy, was it spectacular!

This made the climb worthwhile.

This made the climb worthwhile.

We arrived at the hardest part of the climb; this involves a very challenging rock climb that was billed as a grade 5 climb – the hardest in the book. A heavy chain provides essential support all the way up; this part took us a good 20 minutes to complete.

This is a grade 5 climb.

This is a grade 5 climb.

After resting for a few minutes and taking in the view, I erected my squidpole and long wire antenna.

This antenna is prefect for my Elecraft KX1.

This antenna is prefect for my Elecraft KX1.

Then I began calling CQ. After my first contact (with ZL1BZY) the ants appeared. They seemed as fascinated with what was going on as the other mountain climbers.

Ants on my 7 a/h gel cell.

Ants on my 7 a/h gel cell.

I also found out that their bites were painful!

It's hard flicking them away while trying to operate the paddle.

My new QSO board in use. There are some more mods I need to make.

After making six contacts, it was time to pack up and head back down. The weather forecast was for heavy rain and we didn’t fancy the prospect of tackling the chains in the wet.

We passed some massive trees on the way down.

We passed some massive trees on the way down.

We arrived back at the base of the mountain at 10.24 am and headed for a wonderful cafe in the heart of the Wollumbin National Park for breakfast.

This was the hardest activation I have done so far. I still wonder how an old fella who passed us on the way up did so bare foot. He said he could feel the rocks better that way!

This activation bought home to me the absolute necessity of minimizing weight as much as possible. My back pack weighed in at a hefty 8 kg, and that was without our water bottles. The biggest culprit here was my gel cell, which is far too heavy. I think next time I will use six internal AA cells and sacrifice 3 Watts of power. Either that or I will invest in a  LiPo battery pack. I also took up items that I never used, like binoculars.

Having done most of my climbing in the ACT so far, I was inappropriately dressed. All other climbers were in shorts and singlets while I wore long pants and a long sleeve shirt; far too hot.

So there are always lessons to be learned, aren’t there?