Matching the 2m Colinear for FM

Hi all,

I have described my efforts in building a colinear for 2m over several posts. The base unmatched colinear was sort-of ok at 146.5, but not very good at 144.1, soI set about performing a match for 144.1 using data obtained using BlueVNA and the mrs MiniVNAPRO vector network analyser. This has resulted in a fairly good match, with an SWR around 1.7 and the FT-817 showing only one SWR bar. I can live with that.

Considering a match for FM

Back at 146.5, the FT-817 shows 3 bars. This is not so good – its not a disaster match, but it is not too special either. My earlier analysis suggested that I could put a stub out a few cm further from the feedpoint, but this did not work. I think the reason was that the data I was getting from the MiniVNAPRO was not that good. Recently, I sought to rectify that, as discussed in this post, which the discussion relates not only to the extender but the base MiniVNAPRO as well.

With that in mind, I set up the 2m colinear and did some tests. Here is a screenshot of Zplots showing the data I obtained:

Zplots showing resistance and reactance of the 2m colinear at the BNC connector

Impedance at the BNC connector

Just for piece of mind, I ran the analysis with the extender, and this is what it shows:

Impedance at BNC connector obtained using extender, which shows very similar results

Impedance at BNC connector obtained using extender

The results are quite close, and any analysis done with one data set will pretty much be matched from the other.

The T piece for the 144.1 match

As well as the BNC connector for the radio (or a cable going there), I also have another convenient point to consider matching – the same place I have the stub for 144.1 I have put a BNC t piece here to connect the stub (and disconnect it when I don’t want it). I know I can’t use another stub for 146.5 right at this point on the transmission line, but I could use some surface mount components for a shunt, or add an extra piece of coax and put a shunt off that. We’ll first look at the data from this point:

Impedance at the T piece

Impedance at the T piece

The interesting thing about this is that this is an effective transmission line transformation. If I use zplots to consider the effect of 36cm of RG58 on the impedance, I get the very similar results, and there is about 34cm of RG58, plus the BNC connectors in the middle. The results are not exactly the same – the empirical results are a little flatter because of loss in the cable.

The impedance looks quite different, but if you consider the plot on the smith chart over on the right, it is simply rotated nearly halfway around the centre of the chart. This is the effect of a 50 ohm coax transmission line.

Now I can’t use a stub right here, but lets see what linsmith suggests I can do:

Match design in linsmitch showing the untransformed impedance then two steps of transformation

Match design in linsmitch

First up is to use 15cm of RG58 to get to a point where a series stub could match. The untransformed impedance is the pink dots – this is taken from the Zplots data. If you look carefully at the smith chart from “Impedance at the T piece”, you’ll notice a subset of that curve is shown here. The 15cm of coax transforms this to the green dots. Putting the series stub with a short 18cm away then transforms it to the red dots.

Series stubs are more difficult to create than parallel stubs. The inner conductor of the coax must be broken, but the outer conductor allowed to continue. The stub inner conductor must be connected (eg via solder) to one side of the line inner conductor and the shield to the other. This is logistically quite difficult.

I also provided about 5cm of extra coax with another BNC connector on the other end. This will allow me to easily put this segment into the colinear when I want to match to 146.5, or to take it out. When I am operating on 144.1, I do not want this segment with this stub.

Here is the data with the match in place:

2m Colinear matched in the FM band segment

2m Colinear matched in the FM band segment

I didn’t quite get the match quite right, the best match is around 147.3, however I can live with this. A FT-817 shows no SWR from 146.2 all through to 148.

Now why did it not quite match? I think it’s because I might have stubbed about 10mm too short. Such is life. Here’s a linsmith look at this assumption:

linsmith analysis of the match result

linsmith analysis of the match result

Note: I’ve added an extra bit of transmission line to account for the measuring point of the VNA – it’s not right at the stub point. This means the red dots are replaced with a second lot of green dots, with the new red dots after the extra coax transformation – note that these calculated red dots fairly match the empirical data shown in the zplots smitch chart in “2m Colinear matched in the FM band segment” above.

This analysis shows that I might actually be able to take off about 5mm from the stub and I’ll further improve the match. I’ll not do that straight way – I’ve got a big trip to the Australian Capital Territory coming up and the match is already fairly good – good enough that further improvement might have only marginal effect.

Anyway it’s pleasing to have a good match now at 146.5, and I’ll be using this a lot in the next week.

73, best regards, Wayne VK3WAM

4 summit activation around Mt Dom Dom

Hi all,

Again, it’s time to head for the hills and get into some of that SOTA good oil. For this series of activations, I wanted to have a good look at 2m again, and the colinear was planned to see a lot of action. I did take the end fed for 40m, but the plan was to only use it if I could not get 4 contacts on each summit. We’ll see how things go.

Mt Vinegar VK3/VC-005

This summit is between Dom Dom saddle and Mt Donna Buang. From either place, it would take some time to get in, and this was my original plan. On looking at maps, I thought I might be able to get closer access from Acheron Way, and this proved to be the case.

Access can be via Caters Gap Rd and this is a forest road with large aggregate. Forest Explorer shows it becoming a 4wd track, but the road quality remains good. I thought I would use the Cleft Rock Walking Track, but could not find it. That area had been subject to recent logging, so the track would have been destroyed anyway. I proceeded to point 825356 and turned left, to head up the hill. This went through a logging area, but the track remained passable for a 2wd without too much difficulty. I climbed up the mountain and parked about 843345. I could have gone about another 500m before a locked gate about 1km from the summit. In any case, it was a much shorter walk than I had anticipated.

I put up the colinear and called on 146.5 FM. This was going to be the most difficult summit out of the three that I had planned for the day as Mt Vinegar is hidden from Melbourne by a few closer hills that are part of the Donna Buang system. Even on VK3REC, a EMDRC repeater, action was slow – but this was not because I could not reach it. Perhaps people were slow out of bed today. I was able to reach the repeater with just a HT with a 1/4 wave antenna, so I was able to keep the FT-817 on the colinear. I eventually had to try 144.1 SSB to get the 4th contact. The stub I have for the antenna gives a good SWR at 144.1, so it is good to see that this project has obtained a good result.

Here’s the operating location at Mt Vinegar:

Operating location at Mt Vinegar showing a squid pole. 2m colinear, a backpack, a FT-817 and other radio gear

Operating location at Mt Vinegar

When operating, it’s always nice to have a good rock to sit on:

The shack at Mt Vinegar showing a rock to sit on, plus the pack, a Wouxun HT, a Yeasu FT-817 and other gear

The shack at Mt Vinegar

With the car closer than planned, I thought I might be able to get to Mt Gordon a little before 11am for the UTC midnight change over.

Mt Gordon VK3/VN-027

This summit is part of the 2013 batch to join the SOTA program in Victoria. It is a summit located between Marysville and Narbethong. Access is via a 2wd track that heads off to the north from Marysville Rd which is shown in Forest Explorer as a 4wd track.

There is some commercial gear at the summit as shown below:

Commercial towers at Mt Gordon

Commercial towers at Mt Gordon

With these commercial towers, I imagined that I would suffer from QRM problems with overloaded frontends and it proved to be the case. The colinear is fantastic at bringing in weak signals, but the downside is an overloaded FT-817 front end. With the FT-817 overloaded, there was no point trying the Wouxun HT.

I was able to get two contacts before 11am, and a good number afterwards. I had enough FM contacts to get the SOTA activation points, but sometimes it took some patience. I was getting into Melbourne well enough, but the QRM would take out the readability of other stations. It came and went, and when it was absent, I had a sub s1 noise floor.

A nice touch at the end was getting VK3PF on SSB at 146.475 This frequency is turning out to be a SOTA vertical SSB frequency of choice, just a little down from the national FM calling frequency. I still go down to 144.1 for the SSB chasers down there still, although most of those have horizontal antennas at that frequency, so there’s a bit of a mismatch with my vertical colinear.

Here’s a look through some of the regrowth (and cooked dead trees) towards Marysville from the summit:

Marysville from Mt Gordon, with some dead trees in the foreground. The slopes of Lake Mountain can be seen in the background

Marysville from Mt Gordon

Here was a good view of the Cathedral Ranges from Mt Gordon:

Cathedral Ranges from Mt Gordon

Cathedral Ranges from Mt Gordon

Mt Dom Dom VK3/VN-017

Call me irrational, but a high profile search from a few years ago had me edgy about this place. Still, Mt Dom Dom likely to be the easiest of the three summits to activate on 2m, so the HF antenna would remain unused. I headed in from Dom Dom saddle to about point 813382 on what is marked a 4wd track but is a narrow but good 2wd track. The point where I left the car is about where Forest Explorer shows a walking track. This walking track does not exist. The southern side of Mt Dom Dom has been logged in recent years, so the growth is not too bad. I headed up the side of the mountain “following my nose”. Most of the time it was ok. I think the best approach is to head up the middle on any old logging vehicle tracks that still exist. In a few years, the whole place will be overgrown and access will have to be via the more mature forest on either side of the recently logged areas.

Here’s a look at my operating location there:

Operating location at Mt Dom Dom showing the squid pole and radio gear

Operating location at Mt Dom Dom

Action was still a little slow from Mt Dom Dom. I was getting strong reports from those who did come up from Melbourne, but there were not too many of them.

Got a nice view looking back towards Melbourne from near the summit. See if you can find my car:

Watt River valley and Melbourne from Mt Dom Dom

Watt River valley and Melbourne from Mt Dom Dom

A highlight of this activation was a QSO with Glenn VK3YY on Britannia Range VK3/VC-011. Mt Donna Buang is in the way, but we were able to get the QSO home on SSB. I’ll need to find out from Glenn what antenna he was using.

Mt Toolebewong VK3/VC-033

My final activation was actually an unplanned one, but because I was running ahead of schedule, I was able to put in for a bonus summit. Signals from here were stronger into Melbourne, as more paths were unobstructed. I had a lucky one at the end with Peter VK3ZPF, who called on 146.5 halfway through packing up, but I left the HT on. We were able to exchange reports, but I still had the colinear up in the air. This allowed us to compare the 1/4 wave “rubber ducky” with the colinear. Both ways were significantly up with the colinear.

And with that, it was time to head for home. A nice day with 4 new summits to add to the uniques collection and 18 SOTA points.

Regards, Wayne VK3WAM

2013 John Moyle Field Day

Hi all,

The John Moyle Field Day is a Amateur Radio contest conducted once a year. It, along with the VHF/UHF field days represent the four major line of sight frequencies based contests in Australia. The John Moyle field days (JMFD) also have a substantial HF component that is not present at all on the VHF/UHF field days, and while it also allows activity right into the mm bands, typically operators are exiting stage left at 23cm or 13cm.

It’s a good contest for backpack portable because of the 6 hour section. It also rewards repeat contacts on CW and Digital modes, unlike the VHF/UHF field days. I am finding that I am able to operate chasing contacts nearly the whole 6 hours rather than lots of CQ’ing.

Mt Torbreck VK3/VN-001

Last year I participated in the JMFD from here, and I decided to do the same again this year. Mt Torbreck is the closest 10 point SOTA summit to Melbourne. It has no commercial radio equipment on the summit and is not accessible by road. There is only slight obstruction into Melbourne, so with a reasonable antenna, one can work HT stations on 2 and 70cm. The JMFD has a distance component, and Mt Torbreck is a good distance away to get many Melbourne contacts into the higher point distance bands. A number of JMFD stations also head southwest and west from Melbourne for the field day and this means that those contacts are high value. The EMDRC normally activate Mt Cowley as VK3ER for this contest and Mt Torbreck has LOS to Mt Cowley, about 222km away. Incidentially Mt Cowley is VK3/VC-022, but VK3ER drive to the top and use generators for their high powered station, so they are not a SOTA contact.

Mt Torbreck is accessible by a 2km walking track which climbs about 300m from the car park to the west of the summit. The walking track is steep and good shoes or boots are a plus. It takes about 50 minutes to climb up and 40 back + extra if carrying a lot of weight. I was carrying a lot of weight on this trip.


I normally plan to make two trips up because I have too much stuff for one trip. The stuff to be carried up includes:

  • Yeasu FT-897 all mode rig
  • Yeasu FT-817 all mode QRP rig
  • 2 squid poles for a 2m and 70cm colinear antennas
  • 6 1.5m al segments to make 3 times 3 metre poles for various antennas
  • A turnstile antenna for 6m. This uses four 72cm M10 al segments with M8 taps to screw in 4 more 75cm segments to form two dipoles that are perpendicular horizontal polorization. There is an effective ugly balun for 6m near the feedpoint with a female UHF connector
  • A quadruple quad antenna for 2m, which comprises of 10 al segments. There are two fiberglass poles about 50cm long to mount at the bottom and the top. This goes through a 2 PVC pipes that join together so that they are just over 2m long. This is mounted on the pole by a small al segment to offset it, and a bit of sticky tape to provide a shunt to ensure that the PVC remains vertical
  • A similar setup on 70cm but here I have two quadruple quads
  • 12 Turngy 3S 5000mAh LiPos. I put 3 in parallel x 2 in series when using them, so I effectively have two rounds of this
  • A 12V down DC-DC converter sitting on the output of the LiPo array
  • 3 Turngy 3S 2.2mAh LiPo packs to power the computer for a while
  • A laptop with a supply that takes a 12V input
  • 12 18650 lithum ion cells in 4 lots of 3 in series. Each one can be used to power the FT-817 for a while – my typical SOTA power setup
  • A pile of Anderson Pole terminated power cables, including four 1 to 3 Y cables
  • A collection of LMR195 and LMR400 cables. The 195 cables have either BNC or UHF connectors. The LMR400 are all N connectors. I also brought up a pile of converters. I typically use UHF on 6m and BNC/N on 2 and 70. The FT-897 has a UHF connector for HF/6 and an N connector for 2/70. The FT-817 has a UHF and a BNC connector which can be configured through the menus
  • A one man tent to keep me out of the sun and the forecast showers
  • A MiniVNAPRO and the extender to do some tests on the antennas to ensure all is ok
  • Some plyers, shifters and other misc equipment to do any small repairs to equipment if that proves necessary
  • A collection of HT radios for 2 and 70. The idea being to use these for FM on 2 and 70 for at least some of the contacts to save power
  • Some headphones
  • A CW touchkeyer
  • A Signalink USB for digital modes, plus my Phone/Digital interface for a backup if required

For those who follow my SOTA activations, you would realise that this is far more than I normally take. You may realise why two trips are needed. Practically this means walking UP then DOWN then UP the mountain before the start of the contest, then DOWN then UP then DOWN at the end.

The setup

Upon arrival after the first accent, I put up the tent and piled the stuff in. Carrying all that LMR400 cable, the FT-897 and the 12 LiPOs certainly was a lot of weight and it took 1:10 to get up. I headed back down and got the remainder of the stuff, and it took 40 min down and 50 min up. First was getting the squid poles up. My 2m colinear has seen a lot of SOTA action, and a little stub I made up for 144.1 works well. Very low SWR – nice one. I use it without the stub on 146.5, with SWR around 2. With the stub for 144.1, 146.5 has a SWR around 3.

The 70cm colinear is short, with the good oil around 455MHz. I planned a stub for this to get 439 at least in the game, but I was not successful. There will be more about this in another blog post in the future, but for now I could not effectively use this colinear – what a shame because this was going to be the main game on 70cm vertical. I put up one of my whip antennas on the squid pole about half way up and fed it LMR400 cable back to the radio.

Next up was the 6m turnstile. This is pretty quick to put up. This is not a gain antenna, but it is enough to put me in the game on 6m and it can break up quickly to go in a pack. It gives an SWR below 1.5 at both 50.15 and 52.15

Here’s a pic of the 6m antenna in the foreground with the two squidpoles in the background, plus the operating tent. You can see the trig point to the right in the trees:

Operating location at Mt Torbreck with a 6m turnstile, plus 2 & 70cm colinears on squid poles

6m turnstile, plus 2 & 70cm colinears

The 2m quadruple quad was next. Last year I had two of these in an array, but they were too phyisically heavy to put up, so I jury-rigged up one. This year I did not bother with an array, just going for one with some work to mount it more effectively. There’s a pic below. It was well below 1.5 SWR at 144.1 and around 1.7 at 146.5.

2m quadruple quad at Mt Torbreck

2m quadruple quad at Mt Torbreck

I had thought of trying a longer pole but I would need to use stronger materials. Another idea is to mount it on a squid pole. I’ll think about this for next year, but this will be asking a lot more of the squid pole than a wire inverted V, end fed or a vertical on HF. Why a quadruple quad? Because it is roughly equivalent to a 15 element yagi, especially if I can get it off the ground a bit more.

Finally it was the 70cm quad-quad array. Here’s the pic:

Array of 70cm quadruple quads on Mt Torbreck

Array of 70cm quadruple quads

One of the quads didn’t work so well, and time was running short, so I simply used the other one. Their feedpoint impedance is reported low at about 25 ohms. I’ll need to look into this some more, but I wanted to get operating at around 1:30 to 1:45pm so off I went.

The contest

It started lightly raining about 12pm, so I was a little reluctant to keep the MiniVNAPRO out in the elements. A few mad dashes and doing some analysis on the computer. My plan with the computer was to run it on the three 2.2Ah LiPOs directly until they were flat and then run it on the main supply for an hour. I could then run the computer on its own batteries for the rest of the time without them running out by the end. This worked well, but the 2.2Ah LiPOs gave me more time than expected. Nice to get more than you expect! When the LiPO monitors were reporting individual cells on the 2.2Ah batteries down to 3.55V, I pulled the computer out.

The whole 6 hours of operating was quite fast and furious. Most of the action was on phone, but VK3ER had a digital setup, at least on 6 and 2. They also had CW on 6/20/70 so there was some good triple dipping. I used Fldigi for PSK, and was more comfortable using it in the end in my one man tent lying on my side trying to type on a computer with the pouring rain outside than what I was in the middle.

I was also glad I brought the headphones, because the rain was very loud in that small tent. During the worst periods, I would mainly use the vertical antennas, which the main gun was the 2m colinear. The little whip at the end of the LMR400 cable on 70 was just no match for the 2m colinear. I need to get that 70cm colinear going for next year, these babies are just too good to ignore. The colinear being omnidirectional on the horizontal plane was good during the pouring rain because I did not need to get out of the tent to adjust anything. Same goes for the 6m turnstile (although it’s not a gain antenna). Gain on 6m might be a little hard to do given it needs to fit in a backpack along with everything else.

There was a 2 hour sunny period during the middle of the contest. This allowed me to get a bit more relaxed and I made more use of the quadruple quads. Towards the end it was raining again, but I really wanted some nice juicy contacts north into VK2, and my 2m q-quad was able to get them.

As for power, I already mentioned that the 2.2Ah LiPOs powered the computer well. I ended up not even using half of the 5Ah LiPOs, the first set of 6 were only 80% used at the end, with cell voltages around 3.75V. The “knee” on these is at 3.65V where the voltages start to fall away more quickly. I was hammering away with FM at 50 watts on 2m, but the LiPOs and the 12V regulator powering everything were stone cold. Not even lukewarm. This was a contrast to last year because my old 100 array of 18650 cells could not handle it. The LiPOs are just so much better for this usage.

Come 7:30pm it was finish time. I ended up not even turning on the HT’s. I barely used the FT-817, which is a major change from last year, where because of power constraints, I made most FM contacts on the HTs, and used the FT-817 for a fair amount of the rest. This year, the FT-897 was used for every scoring QSO. Did I mention that half of my big LiPO’s were not even touched? 🙂 I just had to make sure that at least 4 QSOs were at 5 watts so I could keep my QRP SOTA activator’s endorsement intact.

Packing up

So contest finished, and it was time to go home. Too much stuff there to just leave it – although the thought did cross my mind as to what would happen if I just walked down the mountain with all that stuff still up there! It was raining again and it took about an hour to pull down all the antennas. With all the wet conditions, I needed to be careful getting the fragile computer back down the mountain, so I thought I’ll go easy on the weight on the first trip, but still enough to hopefully not have a tonne of weight on the second. One thing I’ll need to make sure of next time is to split up some of the LMR400 cable on the trips because this stuff is heavy.

I left on the first trip down at 8:30, left the car to go back up at 9:20, packed up the tent and did my final checks to make sure nothing was being left and departed Mt Torbreck at 10:20pm for the last time. I arrived at the car at 11:15. It was slow the last time with the heavy pack and the slippy wet conditions on the way down. At least it had stopped raining. I was very tired for the drive home and needed a 15 min powernap in Healesville to keep things safe. My wife thinks arriving home at 2:30am is crazy but it was a very good day with 92 contacts and over 1440 JMFD points.

Regards, 73, Wayne VK3WAM

Three summits around Central Vic Radiofest

Hi all,

Ron, VK3AFW organised a table for Summits on the Air to use at the Amateur Radio Victoria Central Victorian Radiofest, Sunday 10th of February. This was a chance to spread the word about SOTA. I also gave a shortish presentation of 20 minutes about SOTA. Given the trip up to Kyneton, there was a chance to have a look at a few activations on the way.

Mt Macedon VK3/VC-007

I decided that all my activations today would be 2m only. I took the colinear, and had done some work to improve the match, as discussed in Constructing a 2m colinear Part 2. Unfortunately, RG58 is a bit of a pain to work with, because if a little too much dialetric is stripped back, the centre conductor can push back and cause a short in the connector. This happened to me where I put a connector in for my stub. I had to move the stub a little further back, so now I was only going to try to match for 144.1, and leave 146.5 at about 2.5 SWR – make another stub for that later. The stub was tested at a SWR at about 1.6 SWR. This is close enough for me, given I was not actually trying for a 1:1 match, and the point of the stub was not exactly controlled!

I operated from the very impressive cairn that marks the summit. It was a bit foggy as can be seen in the picture.

Large cairn incorporating a trig point at Mt Macedon summit

Mt Macedon summit

The tower seen in the background overloaded the front end of the Wouxun, so I had to use the FT-817 for everything, including FM. The 817 was struggling a little on 144.1 SSB with interference. Still it was a good session with a varied number of contacts from different places, but none quite like Glenn VK3YY picking up a near 600km contact from Renmark from here on the previous day.

Here’s a look at the operating location. Glad I brought the foam for a nice dry place to sit.

Radio and other operating equipment used at Mt Macedon

Operating location at Mt Macedon

With that, it was time to go to the radiofest for a few hours and then the next activation of the day.

Mt Cobaw VK3/VC-015

Accessing this summit was a little interesting. I first headed up Prendergasts Rd, which was shown on a Vicroads directory as a through road. It is not. Perc Boyers Lane goes off it, but is a rough 4wd track only. I headed back and tried then using Reillys Rd from Burke And Wills Track. Reillys Rd is a good quality 2wd gravel road. Burke and Wills is sealed. Camp Track is marked on Forest Explorer, but actually appears to follow a 4wd track at 918777. This has some huge ruts, so it was only 50m in on the 2wd before parking and continuing on foot. It was easy to find Soil Pit Track and I headed along this to about 907776 and then headed due west off track for about 200m to access the summit. There appears to be a track coming in from the north from Camp Track to the summit as well.

Here’s a pic of the final approach to the summit. Easy off track walking.

Forest on the final approach to Mt Cobaw from the east

Approaching the summit from the east

Again, I operated only on 2m. Action here was all FM, with quite a few s2s to be had. There were a few trying out SOTA after the Radiofest. Without any commercial sites here, no problems using the Wouxun on FM.

Pretty Sally VK3/VC-034

The final summit for the day was Pretty Sally, which is only a short distance north of Wallan. The summit area itself appears closed to the general public, but Old Sydney Road enters the activation zone. I operated from a spot near the Beauview Dr junction, northwest of the summit. This had the effect of putting me on the wrong side of the hill for a lot of Melbourne, but it turned out I still was able to work people from the eastern suburbs through the hill.

Again, a 2m activation, most on FM, but one on 144.1 SSB. Here’s a few picks of the operating location and the colinear in action. The colinear works well, but it means there is more unwanted signal also coming in to overload weak radio frontends. Here, the Wouxun could not be used, but the FT-817 was ok.

Radio and other gear operating at Pretty Sally

Operating at Pretty Sally

Colinear on a squid pole at Pretty Sally

Colinear on a squid pole

With that it was time to head home. Three new summits to add to the collection. On the way home, I noticed that a small fire had started on the William range area, near where Rik VK3KAN had been earlier in the day. It looked like it was just a few hectares at that stage. We need some decent rain soon!

Regards, Wayne Merry VK3WAM

Activation of Rocky Peak VK3/VN-009

Hi all,

It’s been a little while since this activation, as I came back from this trip and headed off on another, but here goes.

Rocky Peak is a smaller summit in the Eildon National Park, between Jerusalem Creek and the Big River, south of Lake Eildon. I was in the area, camping for a few days on the Rubicon River and thought I might be able to sneak away for a little bit of SOTA action one morning. I had already activated most summits in this region, but a few around Lake Eildon remained unactivated. It’s always a good thing to add a new fresh summit to the unique SOTA summit activation score.

Rocky Peak VK3/VN-009 can be accessed from the Eildon Jameson Rd, before Torbreck Station. The road basically winds its way around Mt Torbreck, on the lower slopes and then hits flatter ground. After one track on the left and on the right, Taylors Creek track (at ref 102659) to take is on the left. Forest Explorer marks this as a 4WD track, but it is quite passable in a 2WD. I had planned to walk the track, but was able to keep driving up. The track goes over a water course and then climbs the western slopes of Rocky Peak. going up to the junction with the Pinnacle Track at 115677. Turning right to remain on Taylors Creek track, the road continues to be passable in a 2WD, in dry conditions, and I proceeded up to 124667, where I parked the car.

It was a shortish climb up to a nearby high point to the north of this point, and then I picked up some red flagging tape and a faint walking pad that made its way up to the summit along the ridge line. It was fairly easy going, but one thing to watch out for is some sharp grass near where I parked the car. I was wearing shorts and got a number of remarks later about cuts to my knees. Might be a good idea to wear long pants on this summit.

Here are some pics from the summit:

View of Big River Arm of Lake Eildon from Rocky Peak

View of Big River Arm of Lake Eildon

View of Jerusalem Creek from Rocky Peak

Jerusalem Creek from Rocky Peak

Here is a look at the operating location, with the FT-817 positioned on a rock:

Operating gear at Rocky Peak

Operating gear at Rocky Peak

I managed to get to the summit shortly before 11am, which is midnight UTC. Peter VK3PF was operating on VK3/VE-093 as part of an extensive post Christmas SOTA trip, so this convinced me to operate both sides of UTC, and now spoil my 100% unique activation, by having two full activations, one each side of UTC midnight. No extra activation points for me, but it did mean I picked up the chasing points twice. I think we might see a lot more of this come February and onwards when the new SOTA S2S award gets started.

All in all, not a bad morning, and it was back to the family to enjoy camping for the rest of the day.

Regards, Wayne VK3WAM

3 summit activation: Mt Mitchell, Sugerloaf Peak & Federation Range

Hi all,

After my building of a colinear antenna for 2m, it was time to try it out, and what better than a SOTA activation. I picked three summits that were close to each other, and where it was possible to get into Melbourne on 2m, but only one of these summits, Federation Range VK3/VN-003 had anything that was close to line of sight.

Mt Mitchell VK3/VN-012

After getting my gear together early on Friday morning, I headed out (about an hour late) up to Mt Mitchell. There is a well made gravel road that leads up to close to the summit. The main 2WD road skirts the edge of the activation zone, getting about 5m into it. So, it is best to park the car a little down from a junction NE of the summit with a 4WD track. This track is mostly in the activation zone and passes over the summit to the north and then the west. Being 2m, I wanted to be at the summit itself to get good takeoffs in most directions, especially south and west. Approaching from the north west meant summitting.

The vegetation is recovering from the 2009 bushfires. The fire here was intense and killed nearly all the trees. Regrowth is currently about 2m high and is not too bad to get through. There are also rock areas about 10m across to make things a little easier. I found one of these close to the highest point and set up here to operate.

I was wondering how the colinear would go with electrical shorts, and it was no surprise to find that a short had developed when I set it up. Thus began a process of taking down the squid pole and checking the various connections. One thing that I have noticed is that because I used RG58/U – to obtain a shorter antenna – with a stranded centre conductor, the setup is far more susceptible to shorts. When I did the soldering, I did not have the best light. I am going to have to resolder the connections and ensure all strands of the centre conductor are captured by the solder. As it is, there are free strands that make their way where they are not supposed to.

After about 20 minutes of stuffing around, I managed to get a short free colinear. I was running way behind time, so I did not bother getting a VNA readout of the colinear. It has acceptable SWR over the whole 2m band, but it could be optimised as it looks like the centre point is at the top end of the band. This means the positioning of the choke on the input cable could be pushed out a little.

The colinear worked well. I was able to make a contact with Peter VK3PF down in Gippsland, even though there are quite a lot of hills causing obstruction over the path of well over 100km. Clearly this thing has some gain. The only comparison that I made was into VK3REC, an EMDRC repeater. The 1/4 wave on the HT could break the repeater. The RX was scratchy, so you had to move around a little. The Colinear had it well over 5 and 9 plus (I guess 20dB). So I need to fix up the shorting problem to get this baby on the air more often.

I was present at the activation area for about an hour, but with the stuffing around to locate the short in the colinear, I only operated for a little less than half an hour. I headed back to the car, grabbed some quick lunch at Buxton and headed for Sugerloaf saddle underneath Sugerloaf peak in the Cathedral Ranges State Park.

Sugerloaf Peak VK3/VN-011

I have been to this summit twice before. The first was many years ago, when I was not very experienced in overnight walking. We (my wife and I plus some friends but I cannot remember now who they were) camped at Farmyard, about 3 km to the north. We planned to head down to Sugerloaf Peak and return to Farmyard. It was overcast and foggy. We never made it to Sugerloaf due to a few spots on the “track” that were very exposed on the rock.

My second attempt was as part of a warm up for a 16 day walk in SW Tasmania. I was walking with a guy to train him up physically for the Tasmanian walk. He is an experienced rock climber. There is a path that goes up the side of Sugerloaf Peak that he said would be graded 3. He said it is much harder when carrying a full pack. Nonetheless we went up. I would have never have gone up without him, but he clearly knew what to do. Foot here, press against that, move other foot there, etc. I just did what I was told and he made it look easy. I, of course, had no idea of what to do. The tables were turned a few weeks later in SW Tasmania, where luckly I knew what to do out of the group that went down.

So for this my third visit, I headed up the “less hard” track, which still has lots of open, exposed rock. It would be tricky when wet, but in dry conditions, just take good footwear, and don’t look down too much.

Also, since the fires, there has been an upgrade of facilities at Sugerloaf saddle. There is a nice shelter there now which could fit more people than would ever likely be there at one time, ever.

I made the summit in good time. Check the colinear cable – no electrical shorts. Looking good. Raise colinear – shorts! Try as I might for the next 45 minutes, I could not find the short. Do I raise the end fed on 40m, or get out the 1/4 wave. This is supposed to be the hardest summit of the day, will the 1/4 wave on 2m even make it into Melbourne? Turns out it did without too much trouble. I did not get any contacts on FM, but SSB saved the day.

I should make mention of the BHI NEDSP1061-KBD noise reduction module here. I have one of these installed in my FT-817, and in my FT-897 as well. It does make SSB easier to listen to, but it can also improve readability where the signal is on the limit. It helped two of my QSOs today, pulling what would have been R3 to R4, and R4 to arm chair copy. If something is R1, it won’t help it, but if it is R2, it can pull it to R3 and you’ll get the QSO that you would otherwise would have not.

Sugerloaf peak is the most scenic of the summits of the day, so here are some pics.

Looking north west from Sugerloaf Peak

Looking north west from Sugerloaf Peak

Sugerloaf Peak, looking north, with sheer drop off to the right

Sugerloaf Peak, looking north.

Notice the drop off to the right on the pic above (click it for a better view).

Squid pole with colinear on Sugerloaf Peak

Squid pole with colinear on Sugerloaf Peak

Federation Range VK3/VN-003

Time for the final summit of the day, Federation Range to the north of Lake Mountain. I headed up to the ski resort and parked in the main car park. This place is D E A D during summer. I headed up the XC ski trails heading north and after about 30 minutes made it to the top. The activation zone is fairly large, but again, 2m makes you want to operate from the highest ground. This time I did not bother to attempt to operate the colinear. I simply plugged the 1/4 wave into a Wouxun KG-UVD1P and started up. I made two contacts on FM, but then things were slowing down. Time to plug in the FT-817 and I got 5 more contacts on SSB. Even Peter VK3PF got a look in. The path to his QTH is not clear, but there is much less in the way than at Sugerloaf Peak. I still think that if the colinear was able to be operated there, he would have got that summit in his log.

The activation here was short as I wanted to try and be out of the resort area by 6:30pm. In the end it was closer to 6:40 when I was back on the Marysville Woods Point rd, but it seemed not to matter. It was an interesting day for 3 summits and 20 SOTA points, all on 2m. It would have not been possible without SSB, but I need to get this colinear working! Even though its first adventure did not quite work out, I think this antenna has already shown its promise and with a little corrective surgery, need not be a pain in the rear end!

One little side note: I took up some 18650 cells, but in the end the internal battery on the FT-817 was able to last through all three activations. It was getting a little tired in the end, and if I had wanted to keep going, I would have needed to plug in the external power. It lasted about 1 hour 30 minutes of operating, but that included quite a bit of FM at 5 watts, which is going to hit it harder than CW or SSB at full FT-817 power.

Wayne VK3WAM

EDIT: There were a few shorting possibilities in the colinear. I used some unused RG6 insulation to provide a shunt on the joins to provide greater structural integrity. The BNC connector itself had developed a short! I have a good crimping tool, but these are the hazards with working with stranded centre conductor coax.

South Gippsland 6 summit activation

Hi all,

I’ve gone off again on one of these three day trips and activated 6 summits. Some say SOTA is a drug of addiction. Where do I get my next hit? Worse, am I a drug pusher because I took Glenn VK3YY and Kevin VK3KAB along, and helped them get 60 SOTA activator points each? Well, Glenn has already done quite a bit of SOTA work before, but Kevin was a first timer.

After a few hiccups, we left the south eastern suburbs of Melbourne before 6pm and headed towards the hills. After a stop, which involved a stop at a cardboard food production facility for dinner, we headed up the Licola Rd as dusk set in. Kevin drove his “Great Wall” 4WD and we made it to a campsite along the Wellington River inside the boundary of the Alpine National Park for an overnight stop. The tables were a nice touch at the campground (photo courtesy Glenn)

Kevin and Wayne at Wellington River campground

Kevin and Wayne at Wellington River campground

Mt Tamboritha VK3/VT-011

It was only a short drive from there up the hill to the start of the walk to the summit. We then headed up to the Tamboritha saddle. We were able to go along the 4WD track to the east of the summit, but parked before the rough stuff. We walked along the WX station track, but left it at the marker which is to the north of the summit. It was a steady climb from there up to the top, but Mt Tamboritha has a flat top, with the highest point at the southern end. Anywhere on the flat top would be in the activation zone.

On this trip, Glenn brought his end fed half wave for 40m with squid pole, Kevin brought an antenna made up of various Buddypole components to form essentially a Buddistick with a single counterpoise, and I brought a squid pole with two antenna combinations. One was my end fed for 40 and 20, and the other was some components from my old aluminium segment vertical with loading coil, plus a new piece of wire that could hang on the squid pole to complete the vertical. This second configuration was to be used for the first four activations on this trip. It is perhaps 30cm longer than my old vertical configuration. I used it with tuner right on the feed point, with a tapped loading coil 1.6m above the feed point. The Ugly Balun which I have described here was also in attendance. This antenna is a little behind the end fed when the other station is in the end fed lobe, but it is still a solid performer; being able to achieve 5 by 8 to the occasional 5 by 9 report. It does give a lower angle of radiation to open potential DX opportunities, however, and this is something the end-fed struggles with.

The main downside of the vertical is that it simply takes longer to put up and take down than the end fed which is 1) couple to the end of the squid pole, 2) raise squid pole, 3) tie wire ends to something, 4) connect radio. The vertical needs still to be connected together, mount the loading coil and run out the radials. I think the squid pole allows me to take off a good 10 to 15 minutes, but it still takes about 30 minutes to setup and 20 minutes to take down. Better than 45 minutes setup and 30 minutes takedown, but not as good as 15 minutes and 10.

Glenn got the good oil on contacts first. Kevin spent some time tuning his Buddi(stick) setup, but Glenns transmissions nearby upset his antenna analyser. In the end, we all got our contacts, my 4th was with Glenn after he left the summit, but then I got a 5th with a FM simplex station on 2m over 150km away setting up for a field day contest happening the following day. I left the summit with a spring in my step.

Here’s a picture of me operating from the summit (courtesy Glenn). The radials of the vertical are somewhat visible, and some of the ratchet band can be seen on the tree, with the base of the squid pole at the ground.

Operating at Mt Tamboritha

Operating at Mt Tamboritha

Here’s a look from the east of the summit.

Looking east from Mt Tamboritha

Looking east from Mt Tamboritha

We headed down much the way we came, but ended up on a track a little to the west of the marked trail, about 100m it worked out. It took us past the WX station and onto the 4WD access track, with the car parked about 700m further away.

Mt Reynard VK3/VT002

Rejoining the Tamboritha Rd, we headed up to the junction with the Mt Howitt Rd and then towards its closest point to Mt Reynard. There was a 4WD track that initially headed a little closer, and then headed south west. Still this enabled us to miss a cliff face. We parked the car at a point where the road began to move further away from the track. Based on the trip, it can be speculated that a walking track to the summit may exist from this road much further along, but I am not sure about this.

After leaving the car, we headed up and over high ground. There was a great deal of fallen timber, which slowed progress somewhat. We crossed a water course, at a point with a bearing of 100 degrees true from the summit, and then began the climb up, which was mostly a comfortable gradient – but with a few kicks. The total trip was about 3km each way, but mostly off track. We did find a track coming up to the summit from the south when we were still about 50m vertical metres down. This track runs off to the south, and it would seem (but completely unconfirmed) that this might end up on the 4WD track that we parked on, but a few km further along.

Mt Reynard has a very large flat top, more than 1.5km long, with a variance of less than 10m. We decided to activate near the eastern end of this, about 4 metres down from the top, but more than 1km horizontal distance! Again, I used a vertical configuration and Glenn his end fed. We also had a few interesting contacts on 2m FM simplex to spice things up. Something else that spiced things up was the large amount of ants at the summit. It seemed like there were nests everywhere. It does make it a bit hard to key CW when you are always trying also to brush ants off!

Here is a pic of Kevin and myself just below the activation area, with the camera looking south (courtesy Glenn).

Kevin and myself on Mt Reynard

Kevin and myself on Mt Reynard

Again, all three of us successfully activated, but this time (and for the rest of the trip), no one ran down the hill to provide a chase. We headed back down the track, but considering its southward direction, we left it and ended up using much the same access route, (bearing about 110 degrees true from the summit back to the 4WD track).

Bryces Plain VK3/VT-004

It was a little late in the day, and also Kevin was worried about the amount of fuel in the car in order to get back to Licola, but the opportunity of a third summit in the day lured us up the Howitt Rd. VK3/VT-004 is a little rise which is not far from the Howitt Rd. There is a reasonable road that actually goes all the way to the top, where there is a commercial tower with a large solar panel. Care was taken to park the car outside the activation zone, but it was only a short walk to the summit, especially when compared to all the other summits on this trip. This summit is an easy pickup, even with a 2WD. It was in the last hour before sunset when we activated. This time, there was a greater variance in our three logs, with me finally picking up some CW DX on 20 and 30 metres.

Here is a look at my vertical antenna:

Vertical antenna at Mt Reynard

Vertical antenna at Bryces Plain

And the sunset from the summit:

Sunset from Bryces Plain

Sunset from Bryces Plain

From there, we headed to McFarlane Saddle where we camped for the night. There were a few other campers here, plus a group that arrived at 9:30pm who immediately left to head down towards Lake Tali Karng. I would think that it makes for cool walking, but the views are not as good by torchlight.

Trapyard Hill VK3/VT-005

Next morning, we pushed back our planned departure time by 30 minutes, accounting for the late finish the previous evening (because we stretched for the third summit). The Forest Explorer map shows two tracks leaving McFarlane saddle, but there appears to be only one on the ground, the east one – even though there is a Parks Victoria sign on this track that shows one track – the west one (wrong one)! The track from a junction about 500m south where a track heads eastwards before Trapyard Hill is true, but the track is quite overgrown and is indistinct when heading across the saddle at point 1442, grid reference 876521 (55H 0487600E 5852100N for those who are unfamiliar with 6 digit grid references – but if you compare the two, you should be able to identify which 6 digits go into the short form). From here there is a first rise, and the track heads up towards the right of this to the flatter ground above. It climbs the summit to its left, missing the summit itself, with the track passing to the north. We left the track underneath the summit, heading up approaching from the north west. It was a steep climb, but not technically difficult. Attempting this summit is easier with a walking stick.

Once at the summit, I ended up getting all my contacts using Glenn’s radio with his end fed setup. I did get my antenna up, but my first attempt did not work with the tree that I strapped the squid pole onto. I got no joy on 20m CW, but the signal was spotted through the reverse beacon network.

Glenn got a pic of me raising my squid pole (strapped to a better tree stump):

Wayne on Trapyard Hill

Wayne on Trapyard Hill

From there, it was back to camp, but this time from the saddle at reference 876521, we headed north down to the Moroka Rd. It was only about 100m away from the saddle. We then walked along the road, with a little bit of passing car dust, back to our awaiting tents. We packed these up, with the pack carry part of the trip about to start.

Picture Point range VK3/VT-003

Now with full packs, it was time to head down the Wellington Plains towards the Picture Point range. Conditions had now become quite hot and the group started to wonder about carrying all of our gear up the mountain. Something else was playing on our minds – the VHF/UHF field day contest. This might mean that a 2/6m activation might make some sense, especially carrying up a FT-817 to give us some 144.15 SSB capability. Still, I decided to carry up my end fed wire, but without a squid pole. It is closer to the ground, and the reports from this setup are not as good, but it does get the contact. Besides, although we appreciate every contact, having a contact with the dedicated SOTAite chasers is worth more to us than some big gun field day station. Sorry, VK3ER/P. 🙂

In the end, we had a clear 2m simplex contact with VK3PF. Considering we could see the Latrobe Valley from the operating location, this made sense. Peter was going to ring around the repeaters to drum up some further action, but it was not to be. I managed a 2m FM contact with Jack VK3WWW operating VK3ER/P on 2m. Jack seemed pretty happy with the contact. HamGPS, an Android app, was used on my phone to determine the 6 digit maidenhead location of the operating QTH for contest purposes. We handed out the numbers, but we did not consider ourselves contest participants. The focus was ensuring that we all left with 10 SOTA activation points, which we did.

Here’s a pic of Kevin operating at VK3/VT-003. You may be able to make out the end fed half wave on 40m strung in the trees behind him, but you may need to click the picture for a higher res view – note you can do this on all pics on this blog:

Kevin operating on Picture Point range

Kevin operating on Picture Point range

On the way back down, we saw this view of the Wellington Plains:

Wellington Plains from Picture Point range

Wellington Plains from Picture Point range

We made our way back to the packs on the Wellington Plains track, and then headed down to our campsite, at grid reference 839462. There is a toilet and a water tank here. Unfortunately the tap on the water tank was broken, so the tank was empty. This meant we had to do a water run down to the nearby Nigothoruk Creek. There was good flowing water down here.

Using a SteriPen

I should mention that after my recent 6 summit trip around Mt Speculation, I believe that I contracted Giardisis from the water I drunk there. It took 8 days for symptoms to show. I thought first that I had Gastro, but it was much worse than that, with the acute phase lasting about 4 days. It has not been diagnosed, but apparently, it is not easy to medically diagnose as the link discusses. Whatever happened, I did not want to experience it again, so I purchased a SteriPEN adventurer Opti. These take 90 seconds to treat 1 litre of water, and I think I can live with that. The SteriPen got its first use with the water from the Nigothoruk Creek. The UV treatment does not change the taste of the water – which this water tastes fantastic.

Wellington Plateau VK3/VT-007 and the Sentinels

The next morning, we headed off early to get our last activation. The Wellington Plateau is a flat top, but there is a small rise to the highest point. We activated just to the east of this, near the 4WD track. This meant that it would be harder to get VHF/UHF field day contacts, unlike from VK3/VT-003, but Kevin did work VK3ER/p on 6m.

Speaking of the 4WD track, yes it is possible to get a car in to this point, but it would take a great deal of effort. The track is very poor, so a very high clearance vehicle would be needed. Also, the access point is through Miller Gap. It would be an adventurous drive!

After wrapping up the activation, we headed down to the nearby Sentinels, which overlook Lake Tali Karng. It’s a great view from up there, but a little hard to get in the pics:

Lake Tali Karng from the Sentinels

Lake Tali Karng from the Sentinels


We met a Victorian Mountain Tramping Club (VMTC) group that had walked up directly off-track from the lake. It took them about 3 hours to make the 600 vertical metres climb. Tough work with full packs – although these packs did not have any radio gear in them. We kept the full packs only for the trip into and out of our overnight camping spot, only carrying limited food, water, and of course radio gear for the trips to mountain tops for SOTA activating.

After the Sentinels, it was back to camp for lunch, quickly take down the tents, and a walk with the full packs for about 9km back to the car at McFarlane Saddle. It was hot work and we certainly appreciated getting back to the car, and getting to Licola for a fuel topup – that’s both petrol for the car and icecream for other refuelling purposes. It was a great trip and lots of fun for 60 SOTA points.

Wayne Merry

Activation of Point Nepean NP

Hi all,

This is a quick post about my Keith Roget Memorial National Parks Award activation down at Point Nepean National Park. I set up near Observation Point, about 500m from the Gunners Range car park. I worked: vk3pf/p, vk3hra/p, vk3up, vk3azz, vk3fd, vk3asd, vk3hy, Vk7or/2, vk3byd/p, vk3afw, vk2agr. The last three were on CW, the rest on SSB. vk3afw was a suprising CW contact on 20m, but all the rest were on 40m.

One little nice bonus was vk3byd/p on vk3/ve-004, which is in the Alpine National Park. While it was not a SOTA activation for me, it was nice to at least chase SOTA, especially on CW. I have not yet been bold enough to do a SOTA activation relying only on CW, the SSB mic has always been there!

I also had another try at PSK31, but there were no takers. I am aware that I have a bit of splatter myself, it looks like the audio input levels on the FT-817 need to be lower than the FT-897.

I’ve updated my Keith Roget map. While VK3PF, VK3ZPF, VK3VTH and likely even VK3HRA are well ahead of me, I still intend to eventually activate all 45 parks over time.

Regards, Wayne Merry VK3WAM

Three summits before the rain

Hi all,

It’s taken a few days to put this posting up, but it is always nice to revisit activations.

VK3/VW-013 West of England Range

I was up in Ballarat staying with the inlaws for most of the Melbourne Cup long weekend. I have generally taken advantage of getting away during one of the days of these trips to get a few activations, and there are many SOTA summits within a reasonable driving distance of Ballarat to choose from. At this stage I have not yet activated them all, so I can add to my SOTA uniques count. It will be interesting to see what happens after Jan 1 when points for previously activated summits become available for activators again.

The West of England Range is a north south range which is mostly protected by the St Arnaud Range National Park. It is at the northern end of the Victorian Pyrenees. This range is named after the Pyrenees in France/Spain/Andorra for some supposed likeness that I have yet failed to see…..

Anyway, there is a 4WD track that heads north south along the range. Parts are 2WD. I accessed the summit from Redbank using the Barkly-Redbank Rd which is quite passable in a 2WD. I turned onto Centre Rd, but could only go about 100m before needing to park the car and continue on foot. There was about 200m of overall climbing, counting a few ups and downs to continue north along Centre Rd to get to the summit. Here is a look near the operating location:
Near operating location at VK3/VW-013

During operation, I had a 4WD go past, plus some dirt bikes. Conditions were actually quite poor, but I did not have too much difficulty getting the required contacts. It was getting gloomy and a sharp rain shower started, so it was time to pack up. On the way back to the car, a convey of 10 4WD vehicles went by. Obviously a popular spot.

VK3/VW-016 West of England Fire Tower

After heading back to Redbank, I headed up to Stewart Mill and used Teddington Rd to access Centre Rd again, south of the summit. Centre Rd is still quite rough for a 2WD, but I was able to get about half way to the summit, and walked the rest. I was a little closer than what I was at VK3/VW-013 earlier in the day. I operated about 50m NW from the fire tower:
West of England fire tower

Here is the operating gear:
Operating location at West of England fire tower

I had line of sight to the Grampians from here and Allen VK3HRA was activating VK3/VW-002. He was armchair copy with a HT on 146.5FM. Conditions on 40m had improved significantly from what they were at VK3/VW-013, aside from S7 QRN from a noise floor around S1, S2.

I also gave my phone radio interface a go on both 40m and 20m while I was here. It seems to work well on 40m, but it is having a little difficulty holding the PTT open on 20m. Interesting that it is band dependent. My tests on 2m at home showed no problems. I think I will change a few component values to increase the current at the base on Q2, the PTT grounding transistor. This should fix this problem.

After this, it was back to the car for a trip to Mt Moliagul for the third activation of the day. This would involve more unsealed roads, so the car was going to get dirty again.

VK3/VN-024 Mt Moliagul

After travelling for about 45 min, I arrived at the road heading up the mountain. The Google map is a little inaccurate, with the road heading up the mountain a little east of where marked on the map. After sorting this out, I headed up. The road is a little rough, but quite passable in a 2WD in dry conditions. The public road goes all the way to the top, but I parked at a flat section about 40 or so vertical metres below the top, safely out of the activation zone. From there it was just a short walk up to the top where I found a nice spot to activate:
Activating Mt Moliagul

Conditions were similar here to VK3/VW-016. Good signals, but a high level of QRN. It was also getting windy, and a change was arriving when it was time to pack up. I struggled to hold the squid pole up in the wind while I was trying to retract it. Overall, I was quite pleased with the activation, plus the two earlier with 6 SOTA points in the bag when it was time to pack up and head back down. I had one last summit to try for, Mt Bealiba VK3/VN-026, but it had started to rain. We would need to see how this one goes.

VK3/VN-026 Mt Bealiba

This summit is in a Box Ironbark forest with a very open forest floor. I used a road branching off Goldsborough Rd, which got within about 1km of the summit. There are likely 4WD tracks that go all the way up. It would only be a 15 min dash across the very open forest to get up to the top, but given the rain and my lack of wet WX gear, I thought I might give this one a pass for today. Unfinished business for another time.

With that, it was time to head back to Ballarat. 3 out of 4 is better than 2 out of 3 and Meatloaf reckons that ain’t bad.

Regards/73, Wayne

FT-817 (& FT-897) Phone Audio interface part 3

Hi all,

This is a continuation of FT-817 Phone Audio interface part 2.

It has been a while since I have posted on this topic, and the principle reason for that is that I was patiently, and then not so patiently waiting for boards that I had ordered. They arrived while I was away on a series of SOTA activations, but I have populated one of these boards and tested. Apart from getting one of the cables wrong – which I needed to fix, everything works quite well. The markings of the rectifier diodes are wrong, but I already knew that upon ordering as that is a bug in the device files in my design software.

There is quite a lot of latitude with the potentiometer settings, both audio in to the phone and audio out. I ended up using a volume level about 2/3rds on the phone. There is going to need to be individual adjustment of these, as it is a function of the phone used, the digital mic setting on the radio and also the need to ensure that the signal is not being splattered. If you do not have access to two radios with one having an existing audio interface – eg a Signalink for testing, then you will require some on air reports to ensure that your audio is at a good level without causing splatter.

Here is a pic of both an unpopulated board and a populated board. For an Samsung Galaxy S2, I used a 12K resistor for R10. Apple devices might need a lower value, around 4.7K to raise the current that the interface draws. It seems like around 600uA is the threshold for Apple devices, but the Galaxy S2 is happy around 300uA.

FT-817 to phone interface

Populating the board is quite straightforward. Although most components are surface mount, they are either 1206 or 0805 size, and I did not even need to use a magnifying glass. I recommend using a temperature controlled iron with a fine tip.

I have a few spare boards, and can make these available for $12, or $25 with the parts, either $A or $US plus postage. Send me an email at if you are interested.

It should be possible to adapt these boards for use with other radios as the connectors at each end are straight inline. On the phone side, most modern devices have ground on pin 3 and mic on pin 4, but many older non-Apple devices are the other way around, ground on pin 4, mic on pin 3. If you have such a device, then you’ll need to wire it that way. On the radio side, RX audio (phone in) TX audio, GND and a PTT grounded to TX signals are required and most radios should support these. The Yaesu radios provide a constant audio input on their data port, but some radios (I believe the Elecraft KX3 falls into this category) will change the output audio based on the AF gain (volume) setting.

73 de Wayne VK3WAM