The John Moyle Field Day 2018: Another successful field day.

Another Field Day success. This time my main goal was to rake up a few contacts during the John Moyle Field Day, operating from Mt Coot-tha in Brisbane with my FT-817 and Buddistick antenna. But this time, instead of squeezing the most out of 5W, I hooked up my new HF Packer miniHFPA2 Edition linear amp that puts out a massive 30W. And the beauty of this is that I would only need my 7 A/H gel cell to power it.

My set up for the day, from left: Yaesu FT-817, HF Packer miniHFPA2 amp, LDG-Z100Plus tuner. Behind: Yaesu FT-70D, Sotabeams powwerpole distribution box on top of 7 A/H gel cell.

I mounted my Buddistick antenna to a BBQ grill behind the operating bench that looked as though it had seen better days. Fortunately the G-clamp just fitted.

The Buddistick did a good job and was easy to erect. I chose it over a dipole as there was no ready method to secure my squid pole close to the operating bench.

Well, at the start of my 40 minute activation, my battery showed 12.69 V and at the end, 12.60 V. And that was after continuous SSB work on 40m. So 9 QSOs later, I was content to pack things up and head for home.


Beating the downturn with the miniHFPA2

Everyone’s been complaining lately about poor propagation when it comes to amateur radio. But I think I have found the answer to my situation, especially considering I run an essentially low power operation.
I ordered a miniHFPA2, a linear amplifier that is made for portable operation out in the field.
This little beauty is the 5th generation HF Packer amplifier that comes pre-assembled, tested and calibrated. All I had to do was to hook it up to my Yaesu FT-817, then feed the output through an SWR/Power meter and Antenna Tuning Unit to my long wire antenna.

All set up and ready to test on air.

I happened to notice, on checking SOTA Spotter, that VK2IO Gerard and VK2/G4OBK Phil would be activating three summits, VK2/IL-001, 002 and 005 on Thursday 8 February 2018.. This would present me with an excellent opportunity to try out the new amplifier.

I tuned up on 40m and responded to their calls. Gerard mentioned that he was receiving me well and gave me a signal report of 569. This was excellent news, given the marginal conditions. I worked all three summits as they were activated and couldn’t have been more pleased. You see, normally my 5W output wouldn’t have been up to it in current conditions.

So what is this little gem of an amp all about?

According to Virgil Stamps, who makes the amps, the aim of his project is to give your signal a boost so you can start making memorable contacts under marginal conditions. It certainly has lived up to that! The amp gives a clean, more powerful output signal from a QRP transceiver with a good balance between output power, physical size and weight. And what’s sure to excite any SOTA or WWFF operator, it can be powered by any battery such as a 7.2 AH gel cell or 4.2 AH LiFePo4 battery. The amplifier provides a full output of around 30-35W with as little as 9V DC, making it very tolerant for outdoor battery operation.

What makes this amp a little different is the heat sink that is secured to the top of the enclosure. It isn’t the more common type that features rows of serious fins; it is a flat metal plate of around 1mm in thickness. And it does the job it is intended to do very well indeed. It lends itself to outdoor use as it can easily be accommodated in any backpack, but care does need to be taken so as not to damage the toggle switches on the front panel.

I particularly like the slim heat sink that is secured to the top of the enclosure.

The amp comes complete with two low pass filter modules (60/40m and 30/20m) but mine came complete with additional ones for 160m, 80/75m, 17/15m, and 12/10m as well. These modules are inserted into place by unscrewing the left and/or right hand side panels of the enclosure. They slip in effortlessly, thanks to cleverly designed guide posts on the LPF boards. I think when I proceed on my next SOTA activation, I will decide beforehand what bands I will be operating on as I think unscrewing side panels in a hostile environment such as on a summit could be a little tricky. Virgil did send along a sealed package containing spare enclosure screws, heat sink compound, two spare MOSFETS and some other items. Great service and attention to detail.

At the time of ordering you need to specify what level of input power you will be using. This could range from 1 to 5W; I chose 5W. Output power is an easy 30W. Spurious products are -40dB or better at 35W, with harmonic content at -45dB or better at 35W.

If you’d like to read up on the specifications, visit the web site


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 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 ( 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.

VHF Packer 6m Amp alignment

Andrew VK1DA pointed out to me that I had inadvertently set the bias on the amp to 0.5A instead of my intended 0.7A. This meant I had set it up for use on FM instead of SSB.

This was easily corrected; all that was needed was to adjust the variable resister while monitoring the DMM.

Now the bias is set correctly, it’s time to see if it makes any difference to live, on-air operations.

All set for SSB now.


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 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.