Amateur Radio

Well… I’ve now been on-air for a little over a month. It has been over that time, I’ve made a number of observations, both about the equipment I have, the technologies, and the underlying culture of amateur radio.

Cultural observations…

Since becoming an operator… it’s amazing how many other radio amateurs you see crawling out of the woodwork… it’s like a secret society. 😉 For the most part, the house of a serious radio amateur is covered with numerous verticals, dipoles, loops and other assorted types of aerial. Their car often has several whips attached. But if you only know someone via some online means … it’s often surprising when you discover they also indulge in the hobby too.

I’m getting to understand how nets work, and how to participate in the field, the social aspects of amateur radio. Still have trouble catching peoples’ callsigns, especially 7-character ones such as my own. (Believe me … took me a while to get used to saying it properly.) But this is all stuff I’m learning… and I’m quickly picking up how it works. 🙂

Station setup…

I’ve got my station reasonably well set up now. A fellow amateur dropped around with a 2m vertical (see left… it’s that big white stick poking through the yagi TV antenna) to stick on the roof, which seems to do a good job on both 2m and 70cm. Eventually I’ll mount this antenna up a bit higher so it is above the TV antenna (presently, there’s apparently a little bit of interference when I have a QSO) using proper mounting brackets, but this does the job for now.

Using BNC-terminated RG58 (surplus from the days when we ran a computer network using the stuff), some T-pieces and 50ohm terminators, I’ve been able to run a feed out to the front verandah of the house where I do most of my work during summer (see right), and another feed into my bedroom.

This works well… my line-of-sight is crap in this part of Brisbane, but with the antenna up high, I’m able to work a couple of repeaters in my local area — namely, VK4RBC and VK4RBN. Out on the verandah, I’ve also got the bonus that it’s nice and cool, with plenty of fresh air, and natural light. 2W of power gets me into VK4RBN reliably… and while the ACMA recently upped the limit on Foundation license holders to 10W on all modes (previously, we were limited to 3W on FM), I still prefer to use only what is required to communicate — I stay QRP where practical. 😉

The equipment…

I’ve mentioned the rig I’m using before… it’s a handheld, a Kenwood TH-F7E. So far, it hasn’t been too bad to use, does everything I want. I use it to listen to and talk with stations on the 2m and 70cm bands, but also, as a portable AM/FM radio (commercial stations), HF radio receiver and UHF CB scanner. Some of the facilities such as visual scanning are really handy. There are a couple of niggles, however…

My biggest niggle with this set, would be its power supply (see left). It’s a wall-wart power supply, designed for the two-pin power outlets used throughout Europe and Northern Africa (Thanks Tim, again :-D). This is fine… you could get a decent adaptor that will take the weight of the PSU, but it seems that’s not how Kenwood do things. They instead, provided this pissy little converter consisting of a 5cm length of cable, with an Australian power plug on one end, and a line socket on the other. I have to rest the thing on the floor to use it.

The stock power supply is underpowered — sure, you can charge the radio with it… but forget transmitting. Plus, notice the toroidal core? I had to put that in, otherwise when tuned to Triple M (104.5MHz WFM), I’d instead hear ABC Classic FM (106.1MHz) and Triple J (107.7MHz). My advice to people buying this radio — get yourself a 12v switchmode PSU, capable of at least 2A. I’m using a 4A one sold by Jaycar, which works — no tuning inaccuracies, no noise, and I can transmit a full 5W whilst charging without the PSU raising a sweat.

The other niggle, is that the power levels are perhaps a little awkward. When powered by external DC power, I can transmit on 5W (high power), 2W (low power), or 500mW (“economy low” power). If I use the lithium ion battery pack it came with, this becomes a choice between 5W (high power), 500mW (low power) or 50mW (“economy low”). On alkaline batteries, it’s even worse: 500mW, 300mW or 50mW. It’d be nice to transmit on 2W when mobile — this was particularly a bad limitation when my limit was only 3W prior to the ACMA lifting this restriction.

EchoLink experiments…

More recently, I’ve started playing around with EchoLink, a system for linking repeaters via the Internet. It’s similar in many ways to IRLP, however has the added feature of being accessible from a computer with an internet connection. The official EchoLink client is a proprietary Windows-only client, however, there are a couple of free/open-source implementations of the client. I tried two… namely:

• EchoLinux (with echogui) — using an ebuild found on bugs.gentoo.org
• Qtel, part of the svxlink suite (ebuild: media-radio/svxlink)

Qtel seems to work quite well, except when idle, it does seem to chew CPU time for no apparent reason. EchoLinux didn’t seem to want to play nice at all, and had many sharp edges. For what it’s worth, the svxlink package in Portage is a little dated now, you’ll find however that renaming the ebuild file to svxlink-080102.ebuild and running the usual ebuild foo.ebuild digest ; emerge foo dance will work just fine. I’m not sure what’s being done to maintain this package — I can’t, as it’s impossible for me to test the sysop functions in it (I’m not permitted to run an automatic station on a Foundation radio license).

The other night I connected to the EchoLink node KB9OHY-R which AFAIK is in the same general territory as former developer cshields — I wasn’t on for long as it was getting fairly late at night… but we may just make contact at some point in the future. (Yes… what was that about not making contact due to being only on VHF/UHF?)

The purists would probably say I’m cheating using the internet to contact people, but hey… in my situation, it’s about the only way I make reliable contact with people outside of Brisbane. And yes, if either one of VK4RBN or VK4RBC were on EchoLink or IRLP, I’d use the network that way. 😉

Anyway… some time at the end of the year, I might look into getting a HF rig. The hamfests are apparently a good way to pick up gear like this, so I’ll wait and see. There’s one coming up in a few months organised by the Brisbane Amateur Radio Club, a club I’m now officially a member of. My big concern is where to put the enormous antennas needed, I suppose I’ll figure that out in due course too.

Well, so far, people may have noticed I’ve been rather quiet on the Mt. Glorious VHF repeater, much to my frustration. Google Maps in the Terrain view, shows why…

In red, are the mountain ranges in my way. In blue, the attempted path of transmission. The green arrow shows my transmission location.
(Map Source: Google. Map data ©2008 MapData Sciences Pty Ltd, PSMA)

I can get into VK4RBC without any difficulty whatsoever. It’s a UHF repeater, and as it turns out, the rubber ducky antenna on my handheld, is just 10mm shy of 1/4 wavelength at the required transmit frequency (433.525MHz, the wavelength is approximately 692mm). So 0.5W gets in without any trouble. But… the antenna is not efficient at VHF — it’s a lot shorter than the 500mm required for efficiency, and I’m also far too low for my already weak signal to make it.

Now… if I take a bus over the hill to Keperra, I can get into VK4RBN with only 0.5W of power. No problem. However, here in The Gap, the only way I’ve been able to do so, is using my transceiver at full power (5W; 2W higher than permitted under a Foundation license) and I have to practically sit on the roof to get my signal over the range.

Using a 1/4 wavelength dipole, strapped to an old broomstick (pictured right), I was able to get in to VK4RBN. But only just … the signal was weak, and apparently, very crackly. Aiken (regular in #hamradio on Freenode) confirmed this — we could make contact, but only just. Thus it was necessary to construct a better matched antenna, and mount it up high, preferably on the TV antenna mast.

Whilst talking with Grant on VK4RBC yesterday, he mentioned an antenna design commonly called, the “Slim Jim” which can be constructed from a strip of 300? flat antenna cable, often used to connect TV antennas. They are fed with 50? coaxial cable — very convenient for my set — and can be rolled up for storage. So for a portable antenna, they’re ideal.

Asking around in #hamradio, Magne pointed to this site, which explains the theory behind the “Slim Jim”. Apparently it’s one of many forms of J-Pole antenna, which is itself, related to the Zeppelin antenna (used with the aircraft of the same name). They perform pretty much identical to the end-fed folded dipole antenna — in theory.

This afternoon, I wandered into the electronics store, and bought a soldered BNC socket, and 5m of outdoor-type 300? twin-lead cable (Dick Smith Electronics are selling it for about 80c/m, other places may have it cheaper).  About 10 mins of work, and I soon had my antenna constructed.   I soldered it to the BNC plug I had purchased.  The constructed antenna is shown to the left (click for larger image).

For the feedline… we used to run a Ethernet local area network on coax cable, and still had literally oodles of this BNC-terminated RG-58 cable lying around doing nothing.  A small SMA->BNC adaptor on the top of my handheld, and I was soon reaching VK4RBN on the 2m band.

Performance was significantly better than the rubber ducky I had been using.  I still had to use 5W of power, but it got through!  I had some interference trouble at points, the cause is unknown at this stage, certainly my questionable antenna building skills can’t be ruled out, but despite this, I had a around a one hour QSO with Ken on the VK4RBN repeater (a regular on this repeater).  This means I should finally be able to join in with the BARC net on Wednesday nights, instead of just siting back as a spectator.

My one observation —  I had planned to tape the antenna up to a fiberglass rod (originally from a tent — the rods themselves have some cracks in them, thus need replacing) and use that as a mast — however I soon discovered that this particular antenna did not like this kind of treatment.  Doing so yielded very poor signal strength, and seemed to cause the receive frequency to shift — picking up some foreign radio station (not amateur).

Whether the two metal cylinders that link the segments of the rod together are upsetting the EM fields, not sure.  I’ll have to experiment further, but if I let the antenna dangle in the open air, with the matching end up the top — it works fine.

Certainly in future, I’ll have to look at something more substantial, but this at least gets me to the local repeater. 😉

Note: This story has been unwittingly picked up by John Edwards’ Election Blog. Please note the individual I speak of in this post is another chap entirely, and just happens to have the same name, as the US election candidate.

Well, this last few days, I’ve been camping once again. This time, at Basket Swamp National Park, which is about 20km northeast of Tenterfield, NSW. We left Brisbane early in the afternoon. On route to our destination, we happened to stop at a service station outside Warwick — whilst getting some ice for our water cooler, I happened to look around, and see this vehicle:

My father said “Go on, take a photo, you won’t see that vehicle again for a long time.” Not being quite the geek I’m made out to be, I said “No, you like it so much… you go take it.” and handed him the camera. He shot the photos you see above (click to enlarge). Well, it wasn’t the last time we saw it… we saw it parked right beside us when we stopped for dinner in Stanthorpe, parked in the campsite the following morning, and again parked in a carpark at the start of the walk to Wellington Rock. Apparently Linus has seen it, and was quite impressed at the time.
We had some fun finding the actual entrance to the national park… the GPS unit in our car had no idea about the roads inside the national park (funnily enough, it did know the roads at Gibraltar… ahh well), thus it directed us to go travel cross-country through the scrub. Some distance down the road, we found the true entrance, which had suffered some erosion during the recent storms in the area. We set up camp around 9:00PM that evening (Queensland time… we don’t pay attention to that DST nonsense).

Day One saw us walking down to the Basket Swamp Falls, which were flowing rather spectacularly after the recent rain. On route, we saw some trees with an odd foreign growth on the top — the photos below show what I mean:

As for the falls… well… the photos speak for themselves… the creek was flowing well…

On Day two much of the group climbed up to Wellington Rock. John & Di Edwards were doing some exploration elsewhere, but we had amateur radio contact. In fact, my first ever successful amateur radio contact, was with John this weekend — apparently his set would only transmit at 0.5W, but despite this, I received a very strong clear signal (S8~9/5) about 1~2km through the scrub. Some of the adventurous ones in the group actually climbed on top of Wellington Rock, which apparently offered some stunning views. I stayed put, capturing some shots of the group that stayed behind:

Kym Schluter happened to notice that Little Wellington Rock was nearby on the map… and in his words, “had to be walked to.” So after some bush bashing, we arrived at the aforementioned rock. I managed to get an almost 180-degree panorama — which I’ll put up once I’ve constructed it. In the meantime, the pieces are here:

My father managed to get a bit further along the rock, and caught these snapshots:

Later that afternoon, we drove up to Timbarra Lookout. Sadly the ladder up to the top of the actual lookout was locked, thus we couldn’t see any of the really stunning views from the top. However, I did manage to get this panorama… which again is in pieces for now.

Last trip I went on, we complained about leeches… well… it seems trip leader, Brian Reid, scored the ultimate prize in leech collection… taking off his gators, he watched this whopper roll out onto the ground. Beside is a 1920 six-pence coin as a size reference… the leech is so fat it can’t move, it just squirms on the spot.

The weather had been pretty good so far. I had the “dodgy dipole” 40m-band antenna (made from 15m of speaker wire — a knot tied at 10m and the pairs split out) and figured I’d go and see what I could hear on the shortwave bands. Well, in the distance we saw the thunderstorms roll in. It at first got windy… then it started to spit… then it poured… then… hale!

Some of the tent sites got a little damp after that… being mostly decomposed granite (similar to Gibraltar) much of the water drained away, however there were still some significant puddles left in certain spots around the camp.

Day three most of us packed up. The weather was glorious as we pulled down our tents, which was great — on the Gibraltar camp, it poured with rain on the last day, thus we had to spend a good week drying out the tent. A few of the group planned to stay until tomorrow, but for the rest of us, the trip out was uneventful.

Well… I’ve done it. I can now add “amateur radio operator” (or HAM radio operator) to my skillset. I’ve kept pretty quiet about this thus far, but needless to say, I’ve been curious about radio for a very long time. Longer than I’ve been into computers.

It’s only recently that I’ve bothered to do anything about it. Having learned about the various modulation techniques (SSB, FM, PM, VSB, DSB) work, I’ve been keen to put some of these theories to practice and actually get a real-world understanding of them. Well, I’m now an amateur operator on a foundation license — this doesn’t give me the ability to build my own transmitters, but the plan is I’ll stick with this for a year, then I’ll upgrade to an advanced license (ditching the rather awkward F in my callsign) after some study. I figured I’d start with the basics that I knew I could achieve, while for the advanced license, there are some gaps in my knowledge that I’d like to fill in first.

Scratching the itch…

If you’ve got the itch too, like I did… this is what you do to go scratch it. This applies to those in Australia only.

1. Get the Foundation License Manual

The Wireless Institute of Australia sell a softcover book entitled “Your Entry Into Amateur Radio — The Foundation License Manual”. Get it, and have a good read. It covers all the basic principles of radio transmission sufficient to pass the Foundation license exam. Much of what’s covered will be familiar to those who have done 2nd year Electrical Engineering at university.

Once you’ve read through it, and made sure you’re clear on the regulations, and how to connect transceiver, SWR meter, ATU and antenna together, and the procedure for tuning the assembly, you should be set for the next step.

2. Do the exam

This may be organised via the local radio club — the exams are set by the Wireless Institute of Australia. To sit the exam, you must first book in advance — if you’re not affiliated with any radio club, you can usually contact one of the group leaders and they can often refer you onto someone who organises the bookings.

You’ll need the following organised for the exam:

1. Government issued photo ID: Either a driver’s license, passport, or 18+ proof-of-age card*
2. A passport photo (dimensions: 35mm×45mm) to be sent with the license application
3. About $100 for the examination, and to cover the cost of licensing (payment made in cash, cheque, credit card…etc)

(* For minors without a passport, guardians can certify a child’s identity, but must bring their own photo ID)

The exam for the foundation license consists of two parts:

• a practical examination, where you’re asked to identify basic electronic schematic symbols, types of cable/connector, how to hook the station up, and basics such as Q-codes and how to give signal reports.
• a 25-question multiple-choice written examination, where you’re asked about basic theory and regulations (the latter, mostly common sense!). Pass mark is 18/25.

Note you won’t need to know about morse code, but you’re welcome to learn about it if you wish. It’s no longer a requirement.

The exam paper will be marked shortly after the exam, and you’ll know that day if you passed or not.

3. Application and Payment

If you’re unlucky enough to fail, there’s no charge, just go back to step 2 and try again. Otherwise, you’ll be able to fill in the forms to actually apply for a license and callsign, the licensing and exam cost is about $100 (a little less, so bring about $10 in change to cover if you’re paying in cash).

The photo you provide will need to be signed in permanent ink across an area of the photo that doesn’t obscure your mugshot. And make sure it’s the right dimensions (35mm×45mm) — I made the mistake of signing a larger one, and had to rush a correct-sized version to the post office to be sent via express post to the WIA in Victoria.

4. The wait

This will be sent to WIA’s exam service in Victoria for processing. This takes a few weeks (limited resources). The WIA will notify you via post when they forward your details onto the ACMA to assign you a callsign.

In my case, my exam happened on the 16th of December last year. On the 14th of this month (Monday) they forwarded my details onto the ACMA, with this notification arriving in the post today. The ACMA were particularly fast in my situation, looking up my surname in their Register of Radiocommunications Licenses revealed that my license had been approved, that my callsign had been assigned, and was valid from now until the 15th January, 2009.

The ACMA apparently send you a license in the mail, about a week after it appears on the site.

Catching me on-air

If you’re up for a QSO, there are a few repeaters in my area (two of them IRLP nodes) that I should be able to access. Sadly, I can only participate on the 2m and 70cm bands, as I lack transmission equipment for HF (the Kenwood TH-F7E I use can receive, but can’t transmit on HF… and I’m not sure where I can string 20m of cable up in the air in our yard). The repeaters I listen to:

• Mt. Glorious Repeater — 147.000MHz FM: This one is geographically closest to me, and I should definitely be around Wednesday evenings when the Brisbane Amateur Radio Club have their weekly net.
• VK4RBA UHF Repeater — 438.950MHz FM: This is the club repeater operated by the Brisbane Amateur Radio Club. Not sure whether this is accessible from my home location, but I may be able to pick it up when I’m mobile.
• VK4XH IRLP Node 6139 — 146.450MHz FM: This one is located on the South side of Brisbane, thus I may be able to pick it up when mobile.
• VK4ACN IRLP Node 6406 — 146.575MHz FM: This is one is geographically close to where I live in Brisbane.

I’m not sure what other repeaters are in my area… I dare say I’ll learn of their existence over time. I’m rather new to all of this, having just recently joined the community… but as I say, I’m happy to meet up with people on the amateur bands, now that I’ve got my license. 🙂