GippsTech Special Edition (May 2009) - A Review
A ripper event! I got a lot out of it.
Roger Harrison - VK2ZRH
GippsTech Special Edition was the event "wrapped around" the WIA's statutory Annual General Meeting (AGM). Previous WIA AGM events included a meeting at Parkes with a visit to The Dish, and a weekend's tourism in Broken Hill. So, this year's AGM, you'd have to say, was the most amateur radio-oriented event so far. Top marks for that.
Much thought and effort by the organisers went into making best use of every available opportunity to cover topics of interest to amateurs, and subjects that were broader than the VHF/UHF/microwave focus of the annual GippsTech events held each July.
1 May, Friday Night
When it comes to the subject of light, nighttime is the right time. So, attendees were treated to two indoor presentations followed by two outdoor demonstrations - both involving lightwaves.
Amateur Astronomy, presentation by the Latrobe Valley Astronomical Society (indoors).
This was very appropriate from several perspectives: 2009 is the International Year of Astronomy, it is 400 years since Galileo turned a telescope on the sky (and discovered sunspots etc), and amateur astronomers have a lot in common with radio amateurs (like, mounting erections in their back or front yards ). With about 30 members, the Latrobe Valley Astronomical Society is not unlike many radio clubs (http://home.vicnet.net.au/~lvas/).
The presentation readily held the audience's interest, ranging over the history of astronomy; telescope technologies past, present and future; and the activities and achievements of amateur astronomers. Impressive stuff.
Lightwave Communications, technical presentation by Rex Moncur VK7MO & Justin VK7TW (indoors).
Abbott and Costello were back in town. The avalanche of tantalising technical details from Rex and Justin was leavened with a series of hilarious (but true!) anecdotes . . . like explaining to a policeman from a patrol car blocking your drive why you were shining a bright red light across the roofs of Hobart . . . or, how to confound rangers in remote parks seeking the source of a mysterious red light, etc. If you want to take up lightwave communications, be prepared for some "interesting" encounters!
Rex and Justin's talk was not just a re-run of their GippsTech 2008 one, but a lot of the same ground was covered to suit a wider/different audience, along with details on recent experiments. Their goal is to extend terrestrial "cloudbounce" lightwave DX to around 300 km (the "theoretical" limit ?). They're two-thirds of the way there. Inspiring!
After the talks, the audience was able to see some telescopes and lightwave rigs in action (with help from Ralph VK3WRE - lightwave DX record holder, VK3). Pity about the cloudy sky, but you can't always get what you want.
2 May, Saturday
Software Defined Radio - Principles and Practice, by Phil Harman VK6APH.
Behold the future of amateur radio technology! Well, it's kind-of here already (eg. SoftRock Radio kits, Elecraft K3 transceiver, etc). Phil did a great job leading the audience through the basics of the technology and then stunned us with the sort of real-world performance being achieved by the "open hardware" coupled with free open source software (FOSS) approach of the Tucson Amateur Packet Radio (TAPR) organisation.
The technical performance of currently available kits/equipment already exceeds that of the top commercial rigs - at a fraction of the cost. And they're cheap to upgrade as development proceeds and hardware component costs come down. What's more, because the "smart" features are implemented in software, in future you'll be able to play with transmission modes not yet invented. Got powerline noise problems? No problem. Digital signal processing (yep, software) can make the problem 'go away'. All unbelievable, but true! I want one!
Tropospheric Ducting: From Ross Hull to present understanding, by Andrew Martin VK3OE (VK3KAQ).
This subject has been one of Andrew's passions since he was knee-high to a 2m Yagi. He has worked in the field professionally. How's that? - getting paid to pursue your hobby!
I've seen Andrew in action previously. The passion shows. This talk was pitched to a broad amateur radio audience and linked the seminal work of the famous Australian amateur, Ross Hull, with VHF DX experiences of amateurs in the 1950s-60s through recent decades and the last year.
Ross Hull was first to demonstrate in the 1930s that VHF signals could be carried over obstructed paths beyond the visible horizon and that refraction from temperature inversions in the lower atmosphere were responsible.
Tropo refraction and ducting has supported many extraordinary VHF-UHF DX contacts and records over the years, the world over. Andrew outlined regions across the world where DX records could be attained in the future.
136 kHz an introduction to amateur LF communications, by Drew Diamond VK3XU.
Unfortunately, I had to miss this one as I was asked to sit-in on the Beyond Foundation presentation. Dammit! I was told by others who attended it was quite revealing and worthwhile. No doubt we'll see (more) articles in AR mag on the topic, presented in Drew's distinctive style.
Am I really on frequency? Locking our radios to GPS references, by David Smith VK3HZ.
David was one speaker in a group presentation on this subject at GippsTech 2008. I had to miss it as my Solar Cycle talk was on at the same time in a 'breakout' room down the hall from the lecture theatre.
Beyond Foundation the next step, by Ron Bertrand VK2DQ.
As Ron was sent home to bed by his doctor as he was about to set off for GippsTech SE, this session was transformed into a "Community Cabinet" on the Foundation licence education and examination system, and the next steps to attract new licensees, ably chaired by Phil Wait VK2DKN. We had a very mixed audience, ranging across teenaged F-calls to, er, senior F-calls, women, assessors, long-time Advanced licensees, Standard licensees, to dilettantes like myself.
With educators and assesssors in the room, naturally, discussion ranged over many issues, but the examination system was particularly scrutinised. Verdict? Working well - within the ACMA constraints - but possible room for improvement.
A Victorian schoolteacher, Ed VK3FEET, attended in company with two of his young - licensed - students. The enthusiasm displayed by Ed and his students was remarkable and a testament to what can be done within a school club program.
The Foundation bands, the coming Solar peak and propagation, by yours truly.
You'll have to find out from others how this went over. In summary - the coming solar peak will be a contest between "Kiss Your Last Big Solar Maximum Goodbye" (to the strains of Chopin's Funeral March) and "Let the Good Times Roll" (accompanied by a chorus of that title from Linda Hopkins).
Whatever, watch the daily 10.7cm solar flux, keep your eye out for sudden commencements and make intelligent use of the A and K indices. Simple, really. [Yeah. Right].
3 May, Sunday
Aircraft enhancement – how to exploit it, by Barry Miller VK3BJM.
Barry is an AE Practioner Extraordinaire, willing to travel to remote grid squares to pick up and give out a few elusive contacts (or not, as sometimes happened).
This was a combination travelogue to out-of-the-way non-holiday places and a practical prescription to exploit opportunities for diffraction from unsuspecting aircraft on the VHF-UHF bands. I'd summarise Barry's presenation as down to earth, but the pun is too obvious.
AE demystified. Well done, Barry.
Microwave Communications, by Peter Freeman VK3KAI and members of the EZARC.
This could have been titled "Plumbing and the Hollowmen" (with apologies to the ABC). Peter went through the broad gamut of the fascinating technologies and techniques available to play with on the bands from 23cm up. Mechanically quite simple antennas with gain and directivity unheard-of on HF (or even VHF, for that matter) were explained and demonstrated. Mind you, you have to take more care with measuring things - learn to use vernier calipers and micrometers. Fibreglass electric fence stakes make good SHF Yagi booms (East Gippsland is "the country", after all).
A lot of DIY can be involved. Or a lot of money. Most microwavers go the DIY route. Fortunately, a lot of ex-commercial equipment is available from time to time at modest cost and is readily adaptable - with soldering iron, sidecutters and plumbers' tools. It also helps to have suitable RF test equipment available among a pool of like-minded people. Assembling a microwave Tx/Rx system offers huge opportunities for interest and satisfaction. But don't expect to work pileups.
Microwaves and field days naturally go together. That seems like a non-sequitur, until you organise for others to get their microwave gear out there, too (or build two sets and loan out one lot ). Peter's field day vehicle setup has to be seen to be believed. It would make an echidna jealous! [Or horny]
Back to the Future - Broadcast Quality AM, by Phil Wait VK2DKN.
Behold another future of amateur radio technology! Phil's first love was 40m AM. It was a lot of fun, he said. Then he got his licence. 40m AM still holds a special place in Phil's heart. You can understand why.
His presentation took the audience on an illustrated tour of AM broadcasting history, AM ham transmitters of the past and a photo shack-crawl of present day AM enthusiasts and their gear. Magic stuff!
The core of Phil's lecture focused on the technology of Class-E solid-state RF amplifiers and Class-D pulse-width audio modulation. If you've listened to stations on the AM broadcast band lately, no doubt you've heard this technology in action. Not that you'd notice!
Phil's homebrew 40m legal limit AM rig hardware (written-up in AR mag a while back) was described in detail. Gory detail. Including the prototype that caught fire! Actually, it was the windings in the output transformer. Common building wire don't cut the mustard in this application. You live and learn.
His Class-E Tx is kind-of "digital RF" as the output transistors are high speed switching devices that "pump" an L-C circuit, which rings . . . and there's your carrier. Similarly, the Class-D modulator employs switching transistors, driven by square waves that are width-modulated by audio from the mic. Oh yes. Don't forget the filter between the modulator and RF final - just to keep it clean.
The technology has distinct advantages over conventional AM in terms of efficiency and ruggedness. OK, enthusiasts admit that it's not that spectrum efficient. But, like a 1957 Chevy convertible, it's fun to play with!
AM, square waves and switching: yup - back to the future.
WIA AGM (Saturday)
Held on the Saturday afternoon, after the morning's presentations and a BBQ lunch, audience numbers held up well. It was all over in 16 minutes - I didn't even have a chance to nod off! There were no cabals of "concerned amateurs" catcalling from the bleachers, motley miscreants clapping and foot-stomping as the chairperson and directors spoke, or scuffles between protagonists across the aisles. Not even a single "point of order, Mr Chairman!" At least, not that I heard.
C'mon guys, the show was no fun at all! Oh. I forgot. Churchill is in VK3, not VK2. I guess one has to congratulate President Michael Obama (whoops) Owen VK3KI.
WIA Open Forum (after the AGM)
With potential for contentious issues to get an emotional airing, the Open Forum proved a model of gentlepersonly decorum. Extraordinary! Commonwealth and state government Community Cabinet meetings, so popular these days, have rather more life in the audience.
Saturday Evening Dinner
Lastly, the "mystery" after-dinner speaker on Saturday night was a cracker - one of the founders from TechTalk Radio (http://www.techtalkradio.com.au). We all learned some new things and had a good laugh on the way through. Thought-provoking, to say the least.
As an amateur radio weekend: value for money. Congratulations to all involved in its conception, development and execution, with special mention to Robert Broomhead VK3KRB/VK3DN and Peter Freeman VK3KAI. Now - how, where and when do we get hold of "proceedings" ?
Posted in the interests of letting everyone know.
73, Roger Harrison VK2ZRH
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