2m FM Simplex Alive and Well in VK1

What a great drive home tonight. Threw out a CQ on 2m FM on the call freq (146.500MHz) while leaving Deakin and picked up VK1NPW (Peter) over in Erindale. Then as I finished chatting with him VK1MAT (Mat) came up on air for a chat while driving out near/towards Bonython (I was on the Cotter Road near Yarralumla Woolsheds); then for the finale we had VK1GT (Graham – sp?) in Kambah break in and join us.

That's right, a nice little impromptu 2m FM Simplex net with three of us mobile.

Greatest turn out I've encountered in over a year I've been calling CQ on 2m on the way to and from work! Hopefully it'll occur again soon, so listen in and add 146.500MHz to your scan frequencies and feel free to join in! šŸ™‚
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LCWO – When to Progress

I'm now up to lesson 24 of 40 with the LCWO Koch trainer and I thought I'd share a tip with other users.

By default LCWO runs it's lessons with a duration of 1 minute. This is much shorter than the G4FON trainer which defaults to 5 minutes. I like this shorter period, but there are problems with it – and in some cases I increase it when still trying to bed down a character.

One of the problems is that in the later lessons when you've got more characters under your belt, not all characters will be sounded in a 1 minute lesson. Indeed, you can have several attempts at a lessons where the new character will not be heard.

This can result in you getting the recommended pass result of 90% for a lesson, butĀ withoutĀ ever being tested with the new character!!

I discovered this the somewhat hard way. I had a couple of lessons which I passed after my second attempt, so I moved on. But then I got a lesson (17) where suddenly I was really struggling and was not sure why – it ended up taking me about 3 times more attempts than usual.

I realised in that attempt there were several characters I was rather weak on, so came up with the plan of doing all lessons a minimum of ~10 times. This meant even if I reach 90% on my fifth attempt I'd stay on that lesson for at leave five more attempts.

But then more recently I was closely watching the contents of a lesson when I got 90% and indeed noticed some lessons I had 'passed' _definitely_ did not include the new character. As a result I'm now even more adamant in doing each lesson 10 times, but also check any lesson I 'pass' to ensure it included the new character. If not, I don't consider myself to have passed the lesson – even if I've done it more than 10 times.

So, my tip:
1) Make sure when you pass a Koch lesson on LCWO that it at least includes the new character; and
2) (optional) consider running every lesson at least 10 times – even if you pass early on.

Good luck!!

LCWO

Earlier in the year I was trying to learn morse code, but then I got lax as I was more focused on my upgrade study. However, recently VK1DR (James) mentioned on the local mailing list he was using LCWO. I was intrigued so went in search.

Turns out there is a very useful site at http://lcwo.net/ that provides a full suite of CW training tools that run on the site and track all your statistics for you. Further, it has the typical GF4ON Koch Trainer style tool but with built in character verifier – so you just type it into the web site as it plays and then submit for validation. This makes things very easy and more like a game that you can play when you get a chance – and a key to studying effectively is for it to be enjoyable.

As a result, I'm now half way through the Koch lessons at 20wpm (10wpm spacing) and loving it. Maybe in another fortnight or so I might be done learning the characters, then I can start getting them at a full 20wpm and maybe be close to finally being able to receive morse.

Go and check it out. Registration is free and instant and then you have access to all the great tools and the fantastic (andĀ encouragingĀ I might add) metrics.

Cheers,
IS

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VK1HOW No More

Well, that's the end of VK1HOW. You'll find that no such callsign is registered with ACMA. However, now there is a VK1IS.

That's right, my callsign has changed again. From now on, I'll be using the callsign of VK1IS.

As a result, over the week-end I'll again be changing the website address – hopefully to http://vk1is.posterous.com/.

Hope to see you at the new site.

Actually, after about seven weeks of being busy every week-end I'm finally free this week-end. As a result I plan to try and finally take some photos of things like my 'new' FSM, my Digital Interface and hopefully my 2el 2m portable beam. Stay tuned!

Second Hand Books

I’m very happy with my purchase of Solid State Design which being out of print I was only able to acquire through Amazon’s second hand book service (via a 3rd party vendor). As a result though, I see the idea of second hand books in electronics and radio a very valuable resource as many of the basic building blocks (at my level) are fairly fixed and have been for quite some time. The only large changing area (at the foundation) has been around transistors and even then books covering those topics were definitely available in the 60s which gives us some 50 years (half a century) worth of useful books.

Sure there are new things with ICs such as PICs and opamps that have come in leaps and bounds since then. But for someone like me, looking for the fundamentals, they’ll be required later but not just yet.

Further to this, there are also the older books dealing with radio and electronics from the era of valves that are readily found in second hand book shops. These have great appeal to me as I do like the idea of going back to basics and one day I hope to build some valve equipment. It’s also great to just see simpler ideas and technology that with some simple improvements (mainly here talking about meeting emissions regulations) they’re still as useful as today! But further, the written style is rather different and indeed one that I enjoy and seems to be of a slightly higher quality – this is not necessarily objective, but it feels as though due to the printed word being more highly regarded a higher quality was produced.

With that long prelude in mind, I’ve recently taken a greater interest in second hand bookshops in the way of focusing on the electronics/engineering sections. I’ve found some gems in the past, but not really purchased anything. But this week-end that changed.

I came across three (of about five I purchased) related to electronics that I just couldn’t help myself but purchase. Two were older and radio specific with the third being modern being focused on transistors. šŸ˜‰

The two older were Volume I and II of the ‘Handbook of Wireless Telegraphy 1938’ published by the ‘Admiralty’. These two volumes used to be published as one, but with the 1938 edition they became two. These were reprinted many times and indeed my Volume I has a reprint date of 1943 and Volume II has a reprint date of 1946.

A couple of things fascinating about these you will see in the pictures are:
1) The old ads – I love them;
2) The reference to the division of the spectrum – it details how it used to be and that a new standard was coming in which indeed is the one we use today (ie. HF at 3Mhz to 30MHz, VHF at 30MHz to 300MHz);
3) The reference to the recent obsolescences of the Spark Transmitter at the ‘International Radio Telegraph Convention of Washington, held 1927’ due to it’s spurious transmissions;
4) The nice simple fundamental circuits of things such as a single valve CW transmitter; and
5) The details of treatment for electrocution (or, what we would call CPR today) in how it has varied (with even just last year the standard taught in Australia is 30 compressions to 2 breaths – compared to when I started it was 4 compressions to 1 breath).

All these fascinating (and useful) nuggets before I’ve even had a chance of a good read.

But the one I am actively reading is the ‘Basic Transistor Course’. This is rather well written in a somewhat light and accessible way, but a way truly resonant with the era in which it was written. Such a useful book, but not something I’ve seen in recent texts – they wish to cover all components at once or indeed focus on the newer more interesting ICs/PICs.

This book was originally printed in 1962 with the version I have being the ninth reprint from 1977. Through it I hope and expect to further strengthen my understanding of the workings and use of transistors. It doesn’t focus on the mathematical methods needed for designing circuits with it, but does cover more depth on the fundamentals than the material I studied for my license upgrades (as that was all I needed).

So enjoy the pictures and maybe the next time you walk past a second hand book shop, stop and stick your head in there. Electronics and Radio is a modern technology, but not as modern as computers so no need to have the latest books. šŸ˜‰

Note: If you look at the full size version of the images you should be able to read the text if you wish.
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Oscillator Success

Osc

It's a minor thing, but a very important building block if one wishes to build a transmitter (or indeed an SSB receiver). As a result, I'm very happy to report that I've built a simple working oscillator on a breadboard.

The circuit I went with is the 'B' oscillator in the image – taken from Solid State Design. Nothing too special, but an oscillator none the less that I was able to test with crystals for both 80m and 40m. (Tried with a ceramic resonator but with no success for some reason – simple drop in place of the crystal appeared not to work.)

Having it run in the shack will I had fldigi monitoring the spectrum on my laptop I was able to see it very strongly in the waterfall and also observe the changes in frequency as I played with the capacitance.

Now all I need is to solder one up with an variable capacitor and then start building some other parts (balanced modulator and amplifier being the two next ones I'm excited to build). Hopefully this wont be too far away, but still rather busy and still a bit more organising of my junk box to make this kind of thing easier.

Been Busy

Well, that's why there's been not much happening here. But hopefully things will change soon.

I've been away most week-ends of late and busy studying for my upgrade exam. But the week-end just gone I successfully passed my AOCP(A) certification so am now again awaiting a newĀ call-sign. But once I've got that, that'll be the end of upgrades. Yay!

I've also grabbed myself a collection of ceramic resonators, crystals and variableĀ capacitorsĀ so hopefully now with study out of the way I can start trying to buildĀ oscillatorsĀ and VXOs. After that I hope to be well on my way to building a transmitter – hopefully just a simple DSB transmitter to start with.

I'm stillĀ hopingĀ to post up about my FSM and my little portable 2el beam for 2m. Hopefully now I'll have the time – with plans of being around home for the next few week-ends. But that said next week I'm doing a presentation at the club on WSPR, so I'll need to get that together too.

Hope you're all well, and hopefully I'll post a bit more soon as things get moving again.

Cheers,
VK1HOW

P.S. Obviously with the new callsign on it's way in a couple of weeks you can expect the site name to change again. But I'll give fair warning before that. šŸ˜‰