First C4FM SOTA contacts in Queensland

Going through the Activator Roll of Honour results for QLD recently, I noticed that there were no results for Digital Voice. Checking the state of play for the other states, I saw that the Australian Capital Territory and Victoria had one each.

It was time to put that right, so on Saturday 23rd June, I headed out for Mt Cotton (VK4/SE-115) with nothing more than my Yaesu FT-70DR hand held radio.

I had activated this summit more than a year previously, so if I logged at least four qso’s, it would count as another activation and my tally would increase by one point.

The climb up to the summit was uneventful and I headed to a clearing that featured a rather tatty picnic table and a good view.

I set the radio’s frequency to 147.400, the calling frequency for digital modes, and the mode to DN (Normal Digital Mode).

I had pre-arranged with Wal, VK4CBW, to listen out for me on simplex. His was the first contact I made. The distance between us was 26.33 Km (16.456 miles) and his Yaesu FT-2DR connected to a beam antenna sounded excellent. I ran a few quick tests too, to see what difference it would make to the signal if I placed my radio flat on the ground while he spoke. It made absolutely none!

Trying to get more height when calling CQ.

I am well used to using FM simplex on summits and noticed immediately that with C4FM there was no background hiss at all. The audio was as perfect as can be, very similar to that of a mobile phone.

I then had a long qso with George, VK4HGT, followed by Phil, VK4MOT and Bob VK4YA. All contacts were remarkable in that the audio was perfect. I think C4FM is far superior to FM analogue and it’s a mode I’ll be using more often in future.

 

 

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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.

First portable operation with the Packer 6m amplifier

I decided to take the bull by the horns and activate a SOTA summit on 6m only, using my newly-built Packer 6m 30W linear amplifier. The summit I chose was Tamborine Mountain, VK4/SE-059.

My rig this time was the Yaesu FT-817 and the antenna was a homebrew 6m dipole, strung up as a sloper.

The rig connected to the amp and the LDG antenna tuner. The battery is a 7a/h gel cell. The power cords are routed through a SotaBeams 4-Way distribution box.

As soon as I put out my first call, the game was on. In the space of a short 30 minutes I had made 15 contacts. Wonderful.

The action came thick and fast and the view was excellent.

One aim of the activation was to test the amp, especially how long the battery would last as it draws around 6A.

At the start of the activation my battery had 12.58V, and at the end, 12.49V. That’s pretty incredible, especially seeing I was operating almost continuously. Input power from the radio was 1W and output 30W.

Another test I carried out (with Peter VK4JD) was to get an idea of the difference the amp made to an actual QSO. On bypass, with 1W, my signal was down some 20dB. So the amp was doing a fine job.

Building a VHF Packer 6m Amp

I was given this kit by Wal, VK4CBW, as he had purchased it some years ago and knew he would not get around to building it.

The kit was produced and sold by http://www.hfprojects.com in America and came well packaged in a series of sealed plastic packets. Everything including the enclosure and heavy duty heat sink were included.

This little amp requires 1W drive for 30W output and features a Mitsubishi RF mosfet module mounted on the heatsink. There is also a filtered Anderson Power Pole DC input that takes 12V at around 6.2A. And measuring only 5.25 x 3 x 3 inches and weighing less than 1 lb, I figured it would be perfect for SOTA or VKFF operations.

I started my working on the well-made PCB.

Populating the PCB

Then I began making the power cable assembly, the RF cable assembly and the switch cable wiring.

The cables were installed inside the top enclosure case.

I had to fabricate a make-shift mounting plate for the Anderson Power Poles as this was missing from the kit. It has been ordered but hasn’t arrived yet. Eager to avoid delays so I could catch the 6m band opening, I made a replacement out of PCB material.

This isn’t perfect but it would do until the genuine item arrives in the post.

After a little fiddling it went in well and did the job.

The mounting plate in place.

Next, the circuit board and amp module were installed and the initial check carried out.

Ready for alignment and the first smoke test.

The bias current had to be set to 0.7A if the amp is to be used for SSB work, or 0.5A for FM. I chose the former.

The bias current set correctly.

I skipped the next step, which was to align the low pass filter as I don’t have the correct instrumentation. But as I had constructed coils L1 and L2 according to the instructions, this wouldn’t be too critical.

The power output test was more important. I connected the amp up to my Yaesu FT-817 (with power wound back to 1W) and attached my homebrew dummy load and an SWP/Power meter. RF output was shown to be a mere 16W. So I flicked the bypass switch and measured the output as 1W with an SWR of 1.0:1. All good there.

Tweaking the coils of L1 and L2 soon produced the required 30W, so it was time to disconnect the dummy load and attach my 6m monoband dipole antenna.

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

Keying down produced the power output reading I was after.

RF out was now 30W with the SWR indicated as around 1.7:1. Not bad at all.

Next, I attached my LDG auto tuner to the chain and was ready for an on-air test.

All set up and ready for action.

The result was most pleasing. I worked a bunch of VK7 stations (SSB and CW) and well as VK2s and 3s. I am in business and ready to take advantage of the summer openings.

Oh, and all reports received were most favourable. Nice clear signals, good reports and clear audio were what most operators reported back: they were all impressed that I was only using 30W – most stations were in the 200-400W range.

Mt Beerburrum VK4/SE-112

Getting to Mt Beerburrum is easy: proceed along the Bruce Highway from Brisbane towards the Sunshine Coast for about 55km. Look for Exit 163, which will take you to the Glass House Mountains Tourist Drive. At approximately 4.8km take the Beerburrum Road turnoff and look out for the sign for Mt Beerburrum Lookout. There are a few car parks here, but rather continue along the gravel road for about 800m to the end, where there is ample car parking.

Park your car here and begin the walk to the summit.

The path to the summit is concrete all the way, but be aware, it is very steep. Classed as a Class 4 climb, the going is unrelenting all the way to the top. But there are many resting places along the way.

The concrete track may be only 700m long but it is deceptively challenging.

Allow an hour for the return journey and be sure to take frequent breaks.

This is a Class 4 climb.

It took us 40 minutes up and about 19 minutes down. And enjoy the views.

Take advantage of the many opportunities to take photos.

There is a small fire tower at the summit. As soon as you spot it you’ll know you are just about there.

The fire tower at the summit.

There is not much open space on the summit, especially if you want to erect a long wire antenna. I made use of a wooden pole to attach my squid pole to. Be sure to put out calls on 2m FM as well as there is excellent reception on the summit. I was able to talk to local hams easily from there.

There is also good phone reception from the summit.

Mt Beerburrum is part of the Glass House Mountain range and is within the Glass House Mountains National Park (VKFF-0200).

Matthew Finders mentioned this summit in his journal.

Climbing Mt Ngungun in the Glass House Mountains, QLD.

One of the most recognizable mountain groups in Queensland would have to be what is known as the Glass House Mountains. Named by Capt James Cook during his voyage of discovery, these remarkable geological formations are what remains from ancient volcanic activity.

Getting to Mt Ngungun, the northern most mountain in the group, is easy. Drive up the Bruce Highway and turnoff down Steve Irwin Way. Then follow the signs to the Glass House Mountains National Park. You’ll find a good place to park your car at the car park in Fullerton Road.

Plenty of parking available.

The track to the summit is well maintained, with good dirt surfaces and rock steps. It is a Grade 2 track all the way to the top. However, there is a short section where there is a warning to beware of cliff edges.

Signposting is good.

The walk up is interesting, through open forest with fern understory. There is also an interesting rock that features an overhang.

Looks much like a cave.

The walking track is excellent but care needs to be taken in wet weather as the rocks could be slippery.

The going is steep at times.

There are excellent views of the local area to make the journey up even more enjoyable. Photography is a must as there are good close-up views of nearby Mount Tibrogargan, Mount Coonowrin and Mount Beerwah.

There is plenty of space on the summit but little shade. And there are lots of visitors; this is evidently a popular mountain for day excursions.

The small trees and rocks provided me with a good spot to erect my antenna and operate my low-powered radio station while enjoying spectacular views.

The round trip took about 2 hours, not counting time spent on the summit. The walking distance was around 2.8km.

Building SOTABeams’ PowerPole PP-4 Way power distribution board

One of the challenges I was having while operating portable was making sure that my power polarity was correct. Fiddling around on a mountain peak with red and black connectors on a 7a/h gel cell is fraught with danger. And when I have two or more components to connect, well …

The answer I found on the SotaBeams web site (http://www.sotabeams.co.uk/).

I placed an order for their PowerPole PP-4 Way power distribution board.

A week or so later, a padded envelope arrived in my mail box.

The contents of the envelope.

Construction was easy as the kit is very simple. All that was needed was a soldering iron and some solder.

 

The power poles ready for soldering.

I ordered the kit only (without the enclosure), so I headed to the local supermarket and bought a cheap plastic sealable container that would do just fine. All I had to do was to cut out a piece wide enough from the lid for the connectors to stick through.

The PCB sits under the lid with the connectors sticking through. I secured it into place with four nuts and bolts.

The power supply connects to one set of power poles and the radio, atu and other items connect to the others. Simple.

Works like a charm. Will make a difference in a park or on a summit.