In The Shack
in a state of flux.

Members at the July Coffee Shop were treated to some facts and figures about lighting and relevant regulation. Just as interesting were the array of lamps, bulbs and elements passed around and the details of light stands at the MCG.
Ray VK3RD, a fully qualified electrician and electrical inspector, confused us with the ‘ins-and-outs’ of Colour Rendering Index, which is independent of the Colour Temperature in Kelvin and the Spectral Power Distribution… but at least the lux, lumens and candelas explanation sounded like radio propagation and field strength measurements.
During the talk, Ray covered the initial technology and evolutionary improvements as well as the specialist uses and light characteristics of incandescent, fluorescent, compact fluorescent, metal halide, sodium vapour, halogen and finally LED technology. On display was a green traffic light LED cluster (discarded after some had failed) and as a special treat, Michael (callsign needed) brought in an antique Edison bulb, apparently dating back to 1904! Robert 3DN took a great photo of it with its owner.

As ever, the club membership had some other insights into the discussion, but none as curious as Andrew 3BFA’s  input about an amateur who’d used only the components from the electronic ballast of a compact fluorescent to construct an 80m-band transmitter! Here’s Michael Rainey, AA1TJA’s writeup of the project.

Peter VK3BFG with a loop yagi for 23cm band.

At the EMDRC’s April Coffeeshop meeting, Peter Cossins VK3BFG presented ‘An introduction to ATV‘ and upcoming improvements to the VK3RTV repeater system. Peter spoke to a larger than usual turnout of club members and visitors, sharing an insight into the current state of ATV in VK3 and his experiences of the last decade and more.

The VK3RTV ATV repeater output is on 444.25Mhz (below UHF28) using two inputs in the 23cm band and one in the 10Ghz range on a first-come-first-capture basis. This frequency is tuneable on all televisions and EMDRC Clubmember Peter Berret VK3PB routinely transmits on Saturday evenings (a good time to tune in your TV for the first time) while most other users are unscheduled. Rather than using expensive to buy and difficult to build combiners, the 3RTV team transmit the audio and video separately via an 8-antenna system for video and a 4-antenna system for audio with good general coverage in almost all directions.

The next step in the upgrade path for the repeater system is to replace the analog output with QAM-16 type digital mode that is common to both the satellite ‘DVB-S’ and terrestrial ‘DVB-T’ standards. This means all newer TVs and digital set-top boxes will soon receive the dual-channel multiplexed digital-ATV output so two separate QSOs can be conducted simultaneously! Those amateurs who’ve experimented with satellite tv will likely already have a suitable receiver in the shack.

Future improvements will focus on the antenna system while the input will remain analog with digital conversion done at the repeater, so existing transmitters will continue to function and new ATV converts will benefit from the lower cost and lower difficulty of building analog.

Further information can be found at the VK3RTV website where you will also find ‘How to receive’ and ‘How to transmit’ articles. Many thanks again to Peter VK3BFG for presenting one of the more exciting parts of Amateur Radio.

I got a call last Sunday night to give Robert VK3DN a hand down at the clubroom. We could really have done with a third set of hands!

VK3DN's Squidpole Vertical MKiii

Standing at over 18.5m tall, with a 9m squid pole atop four sections of 50mm PVC water pipe, and a trailing wire out to the tuner, it’s close to a 1/4wave on 80m and gave an initial 1.5:1, I suppose mainly influenced by the wire’s insulation, the fibreglass and plastic pipes enclosing the radiator and the trailing lead running along the ground. A shorter than desired single radial was also a compromise, but contacts were made with a 5×6 with 100w into a VK2 mobile travelling around western NSW.

While devised for 80m, it’s a pig to put up and VERY scary to bring down. The 4 sections make for too much flex and the 9m squidpole makes it worse. This is the 3rd generation of 3DN’s vertical and will probably live on with 3 plastic sections as a raised 40m vertical with radials along the guy ropes. I might create the same on a single plastic section with base loading for 80m.

More likely, along my previous thinking, I’d like to devise a 20/40m vertical for digi & ssb. with the raised radials on the guys I could even feed it with 50ohm coax rather than a wire to the tuner. It’s easy to create 20m radial by snipping the 40m ones and adding clips for use on 40m. I’m just not sure about switching out the top half of the vertical without having to drop the whole thing and raise it again.

Less guying, less to carry and less setup is what I’m really going for though. I’m also pretty taken by the Moxon Antenna, in particular one by M3KXZ as displayed on the beach. That antenna was the primary reason for sourcing the 9metre squid poles in the first place.

I’ll have the 20m Moxon constructed soon and some sketches of a variety of antennas for 20m and/or 40m bands using the 9metre squid poles.

I was looking for a way to seed a homebrewing Special Interest Group in the Club and decided to create a series of presentations to teach me the things I felt I should have learned but didn’t (due to heavy involvement with running the club rather than participating in the hobby) and eventually provide a path for new Amateurs, particularly Foundation Licence holders.

Knowing that I don’t know much it was clear during the genesis of this Big Idea that I would need help. Andrew VK3BFA, friend and mentor, was the sounding board for my Grand Plan of creating a 3-year, 3-tier lesson plan. In the nebulous logic of the Grand Design I reasoned that we enjoyed 20 club meeting each year and with the expertise around the club coupled with my studying for the Advanced Licence, I should be able to create up to 10 ‘fact sheets’ from topics throughout the year which can be fleshed out into lesson plans for when the topic is revisited, and vice-versa; create lesson plans to be presented at meetings with accompanying ‘fact sheets’. Andrew thinks I’m mental.

With thanks to Andrew’s suggestion and efforts to design and present the topic, ‘Introduction to Soldering’ was the first fruits of this endeavour. I guess I should get started on the fact sheet!

Ultimately I’d like to compile a folder full of presentation topics for future meetings with all the related theory included. The accompanying fact sheets could be handed out on the day, available for download from the Club website or even compiled as a reference, for radio theory, operating practises, construction ideas and even software demonstrations.

The real Pie in the Sky idea is to create a larger project that acts as a library for other clubs and schools to use and swap completed presentations/lessons. Wish me luck!

With a sunspot trough that at times seemed like it would never end, the 20-metre band has been a safe bet for medium and long DX while other bands’ openings have been fickle. ‘20′ and to some extent ‘80′ were the only things on our minds for a while and then the Foundation Licence arrived in October 2005.

WIA President Michael Owen VK3KI writes in the current Amateur Radio Magazine that over 1500 new Foundation licencees have joined the ranks (and many have upgraded) helping swell the number of VK Amateurs to nearly 16,000. As these F-calls don’t have priviledges for 20-metres and the size of 80m antennas are difficult to erect on most suburban blocks, we’ve seen an explosion of activity on the 40-metre band.

With the popularity and looking for fundraising ideas for the club I went out looking for lightweight, field portable 40m antennas and came across a couple of nice verticals that are also suitable for permanent installation at home. They share a similar design and comparing the differences is just as enjoyable as exploring the similarities:

• ‘A 40m Vertical’ by G8OQW shows a simple option with a homemade base-loading coil and sparks ideas for both insulating the vertical from ground and using a spike driven into soft ground when portable.
• ‘40m-Vertical by ON7AMI has engineered a well built alternative that is more suited for permanent installation at home. His detailed article shows a number of photos of the waterproof connection box and the space left inside is begging for a remote-controlled multi-tapped coil for matching to more bands.

Something else to think about is Near Vertical Incidence Skywave (NVIS). As the Maximum Usable Frequency (MUF) almost always allows for reflection on 40-metres, so many Amateurs are relying on this form of propagation without being conscious of the fact. I recommend investigating NVIS and thinking more about your desired outcomes, particularly when portable, but also at the QTH.

Perhaps not as ’sexy’ as Intercontinental-DX, I would expect to see more participation on non-contest Field Days once more Amateurs understand that short and medium distance contacts can be made NVIS. A dipole just a couple of metres above the ground directs most RF upward, is less onerous to erect than launching support ropes into trees and a safe-bet when venturing out portable for the first time or to a place that hasn’t been well explored before. (Near-Real-Time MUF Map)

While low-angle radiation is great for far-off contacts, here in VK3 a portable station targetting other local portable operators can expect greater success without needing great antenna height or high power needed for US and European DX, and can capitalize on other VK operators who are venturing out for the same reasons as yourself without the complications of timezone differences and greyline calculations in chasing QSOs.

While hanging out with Richard VK3TXD last night, I casually asked about the reel of surface mount components he had. Expecting to hear ‘603′ or perhaps even the smaller ‘402′ size, my heart sank when he confirmed they were ‘805’s… the size I’ll be working with on the Pic-A-Star project!

They’re tiny! Looks like a good magnifier is in order!

I’ve had the question of ‘what to tackle first?’ in the back of my head for weeks now. Just a couple of days ago I downloaded Ray G4FON’s Koch CW Trainer software and immediately had it churn out a full 40-character random audio file at 25 words per minute, and three 2 letter files at 25wpm. I was always worried about ever being able to keep up with Morse Code at that speed, let alone learn at that speed from scratch. As it turns out, it’s quite easy to recognise the characters if you disengage the urge to ’speak’ what you’re hearing, even if just under your breath.

I’ve heard before the risks of ‘journalizing’ and not to go through the multi-step process of hearing the sounds, thinking of them as dots and dashes, associating them with a letter, saying that letter and so on. The Koch method, which entails learning at the speed you wish to attain, builds up, one letter at a time at full speed. The Farnsworth method is similar, but begins with large gaps between word sent at full speed, slowly decreasing the pause as you progress in competency.

I presume both these full speed methods (though I can only speak from experience of the Koch method) ensure that you never entertain the idea of a multistep translation. Getting to unconscious competence, where you don’t have to think about something you know how to do, is the final goal in learning any language, indeed any skill, so learning at full speed makes copying code a reflex, not a process.

I’ll admit that I began at 25wpm and had a little trouble. Surprisingly no problem with recognising the characters but it was too fast for me to copy by hand and after 40-50 characters I’d have fallen 2 letters behind and got tangled with worry that I’m falling behind. Then I’d fail to copy a character, wait to the next break between words and continue, again at 100% accuracy! I’m certainly amazed and very proud at how I was able to recognise the first 2 letters at 25wpm the first time I attempted it. Keeping a clear mind and switching off my internal dialogue is the key to success. On my first attempt I was shocked to count 54 characters before my first error, it felt like just 15 or 20!

I’ve since decided to fall back to 20wpm (which somehow seems really slow!) and make progress on learning the alphabet, then numbers and punctuation. G4FON’s software builds from 2 characters to 40 and then allows you to use text files as the source, rather than just random letters.

Once I get to the end of the random training I plan to choose some freely available, public domain classic novels from Project Gutenberg and convert them to audiobooks, or perhaps ‘CW-books’, and try listening to them on my iPod or while I drive. I’ll try 25wpm and higher to see how fast I can copy once I don’t need to write it all down to compare with the program’s random output.

I’m also interested in beginning my homebrew career with some basic transceivers. Eventually progressing up to something like Elecraft’s K-1 and KX-1 kits with all the bells and whistles. I don’t really know how often I’ll be active with CW, but I’m already certain how proud I’ll be when I’m using my new CW skills on a radio I built with my new kit building skills.

I picked up the repeater update for this month and have processed most of the files I usually maintain. The VX-5 Commander software isn’t behaving like I remember it, the Import from CSV is grayed out.

Also, I’ve added a static page to this site where I’ll keep my latest memory files. VK3LOL and I have spoken in some detail about a more intelligent workflow for maintaining all these memory files and I’ll be exploring the options for the ‘base file’ (from which all other files will be generated) in the coming weeks. Do I maintain a database? SQLite? or a text/CSV and do acrobatics in Excel/OpenOffice to produce the different column requirements of the software that accepts a CSV input. That still leaves me with hand updating the Icom 208 and any others that don’t have non-manufacturer software or other options for inputting CSV or converting from other formats.

I have grand plans, which I’ll cover at a later date. I’ll stay quite for the moment so not to dob myself in for a job I’m not able to take on.

I put this one together using the photos from the EMDRC March CoffeeShop presentation by Roger. That would easily have been one of the most interesting presentations in my time at the club (no offense intended to any of our other speakers). Whether it was the simplicity of the mast or that it perfectly solves a problem without over-engineering, the whole idea took-off in the imagination of the audience and sprang into a club project.

I’ll be retaking the photos tomorrow, but all the labels should remain untouched.