Sunday, November 22, 2009

bicycle hacking imminent

grabbed a few bikes from a neighbour that was having a tidy. two BMXs, mainly for the wheels, for the long wheel base(LWB) recumbent that I've been wanting to make for a while. I made a LWB bent over at Lyns place but it has issues and needs a fair bit of work, mainly brakes and gearing. The steering is now sorted.

Also grabbed a alloy MTB that fits well enough and has a disk up front. Put a straight 26" on the back and it feels ok. Need to tweak the chain line, or drop the 1/8" chain for some thing a little more modern.

Been putting more thought into some touring. Still don't have a destination in mind. I think I want to explore the top end of Tassie and some of the northern NSW coast. Those are both big trips, so I think I better start with something smaller, closer to home and flatter =)

So anyone with suggestions of interesting places to cycle tour around Adelaide, Hills and surrounds please let me know.

Adelaide launches a Perl Mongers

Well my last post about the map and what its missing, is now not missing the entry for Adelaide. Although there still isn't a pin on the map.

Once we have had a few meetings under our belt, Adelaide Perl Mongers will get an official mail list, currently hosted locally. Perhaps even a pin on the Map!

All the kudos to Justin Hawkins for setting up the web site and the mail list =)

So please join the mail list over at Adelaide Perl Mongers, so we can get a meeting rolling for some time early December.



Thursday, November 19, 2009

Interesting rant on where programming languages should go

Has some interesting ideas. I suppose it all depends on what kind of programming you do.

Perhaps an alternative would be a tiny thin language that hides the data type to library massaging.
Having to "import os" in python, is an example of why these "modern" languages are stuck in the 70's or 80's etc.

None the less, make me think about the pre-compile vs soft-dynamic languages.

Tuesday, November 17, 2009

There is something missing from this map

There is something missing from this map.

Can you tell what it is?

No, well we're working on it =)

20091117, quote of the day

"Is there and app for that? Yeah, on both. Wait, no, it looks like it was rejected from the iPhone store. Droid it is, then."

Foundation License limitations and restrictions

I have received a number of emails from concerned VK HAMs about the contents of my posts and my 'use' of homebrew transmitters.

It is well known in VK land that Foundation calls are restricted to using only commercial built transmitters with a maximum of 10 watts PEP. However, no other useful or relevant details of the Foundation license seems to be well known.

So let me make two things clear, firstly, I have explored the LCD on all the issues of transmitting and beacons as this is a topic that interests me greatly. Secondly I have not built any homebrew transmission equipment. Only two homebrew receivers and used my Kenwood HF rig and oscilloscope to check that they are not putting out noise on the bands, fundamental or harmonics.

The LCD is particularly vague about the issues around the use of beacons by Foundation license holder. Except that it precludes the use of "computer controller beacons". This does leave plenty of scope for experimentation in analog generation methods. To be honest, in this day and age I believe those most likely to advance this aspect of the hobby are those that grew up in a digital world and have been programming since they were knee high to a grasshopper. However the folks writing the LCD were no doubt born early last century and these new fangled computers will take some time to catch on... I'm not being rude, just a bit disappointed.

That said, I have the basis for a microprocessor-keyer sitting on the shelf, waiting. Waiting for when I upgrade my license.

Which brings me to upgrading from a Foundation license to a Standard or Advanced license. There is a hand book for studying for a Foundation from the WIA, but not the Standard or Advanced. Why is that?

Perhaps this is the reason that there are so many F-Calls out there now? And so many HAMs complaining about there being so many F-Calls. Apparently one more letter is too hard to deal with.

I've tried ordering materials, as advertised on the internet, but unresponsive is the nice way to summarise. Its too hard to get the materials to study to upgrade, unless you are lucky to be part of a club with materials. If you're not part of one of those few clubs, I've noticed they don't share. Why is that? There doesn't seem to be much collaboration in that space. Or I'm just not in a position to see it, because I'm only an F-Call. Its a bit of a catch-22 if you ask me. I;m sure they work hard to produce the material in the first place, but you will get more recognition and more amateurs if that material is shared around the clubs. Free or at cost or more, it doesn't matter. Get those materials out there!

I've been flamed on mail lists for asking about topics that only Advanced calls are allowed to use. So my response was how am I supposed to get my Advanced license if I don't know about these topics, their response is, you don't until you are a Advanced call. There is definitely a weird head space around learning for your upgrade. You are supposed to learn it all yourself and asking for help is cheating.

That said I want to upgrade to Advanced and to tinker with QRSS and build my own kit.
Its just a shame that there is so much attitude around being a F-Call with aspirations.
There are some local HAMs that are very helpful. They have been inspiring, but their time is quite limited. Which is why I try to make the most of my time at club meetings. There are other clubs north and south that would be beneficial, but getting to and from the meetings is a serious hassle. Perhaps I just need to get a car or motorbike of my own as public transport isn't an option, thanks to Adelaide's central hub transport model.

I know that AR wants articles on what F-Call are up to and think, but I doubt they want to hear about the plight of what F-Calls can't do. "Become a WIA member!" and "Upgrade! Upgrade!" I hear folks say...

Anyhow, I've dropped a lot of other interests and other clubs' activities so I can focus on work and amateur radio. Hopeful over the Christmas break I can finish my upgrade study and sit the exams...

Monday, November 16, 2009

building an oscillator

I'm built an oscillator, for 28.188MHz based on the Genesis Q5 from VK1AA. Well, I had smoke. I'm still working on the plug-in-bread-board. I think the lesson is not to use 12 volt gell cells for testing out new ideas. Can supply far too much current too quickly. Now I understand the little 9 volt battery role in life...

The little 74hc04 squealed then popped! Took only a second. I'd put the 7805 in the reverse position. Its a 50-50 chance ... Lesson there is to not turn the pluging board around all the time and loose track of the orientation of things, I think.

So with the regulator in the right way now, it gets pretty warm, so I've added a heat sink, but not tested it again. Will have another go when the 2 meter AHARS net is on this evening, in the shed.

At the end of this, I might order a G5 or two. I expect that I'll need a few for various prototypes anyway. Just want to get a couple of modular oscillators up and running for receivers =)



Sunday, November 15, 2009

new 10m dipole

Replaced the dipole this morning. Cut to length some pvc coated speaker cable that had once been an end fed long wire. Its light and grey so not so easy to see as the red 30amp power cable I was using before. Also ran coax straight up to the center of the dipole and will run a similar arangement to the QRSS Rx of Hans Summers, G0UPL. Now onto modifying the receiver =).



Saturday, November 14, 2009

Saturday works

It was pretty hot today, was forecast to be 39c. Didn't feel like it, but did slow me down running about the place getting the antenna up. None the less I have a dipole for 28.188MHz up. Its currently mounted as the third guy rope of the mast that I ran the old WiFi gear on. The router board that was running the WiFi stopped for no particular reason, so I'm suspecting the power supply section of the board, needs further investigation. I removed all the WiFi gear from the mast and reset two of the stainless steel guy ropes. Made the 10 meter antenna the third guy...

It works, probably not nearly as well as I'd like, perhaps I should build a Z-Match tuner for it instead. So, I setup the little Kenwood and tuned all around 10m. There was some fast CW but little else was heard on the band.

So, the 'ladder line' is a nasty hack. I grabbed a couple of plastic tent pegs and some cable ties. Its not so good, needs frequent adjusting. There was plenty of activity on 40 meters. This little dipole is about six meters off the ground, double the height of the previous dipole for 40m.

Actually it is the 40m dipole with the rest as the ladder line. And lots of string and a couple of eletric fence insulators. The old balun is currently in, but I'm not sure that the 4:1 is appropriate. Is a 1:1 better suited to a ladder line? Sorted out some coax and connectors too.

Dug through some boxes that I picked up at the last AHARS meet, grabbed some bits for to setup the audio into the peecee. Also found a 0C70 and a 0C71 ... I think they are germanium audio transistors.



Thursday, November 12, 2009

QRSS receiver crystal for 10 meters

The 28.188MHz crystal arrived today from Nick, VK1AA. Have been hanging out for it to arrive and would really like to get a receiver up and running.

This weekend looks like being a scorcher, about 38c, so a bit of indoors building will be in order. Which also leads one to think about oscillator stability. With night time temperatures of 15c to day time temperatures of 35+c degrees there is plent of room for drift.

Thoughts on work to do;

  • An antenna for 10 meters; vertical or dipole?

  • If heading down the di-pole route, balanced or OCFD?

  • Maybe a balun?

  • A transmission line should be straight forward, I have some spare clean RG-213.

  • How about a tuner, then how do I measure if its really working?

  • If a vertical, what about a copper cactus or a just a 5/8 vertical?

  • Should I make the local oscillator in a separate box?

  • If so I could drive the Kenwood to TX test ... wonder what specs are required to drive its VFO port?

  • Then modify the 'sudden tunner' style DC receiver. Based on an NE602 and LM386.

  • Hook up to peecee with 96KHz sound card.

  • Grab with glfer or baudline.

  • Announce its ready...

  • Later develop something more focused around web based delivery.

  • Find a design for a non-computer 'controlled beacon'. A condition of the Foundation Licence.

  • Perhaps a beacon controller as simple as a pair of NE555's and a 4017. The first NE555 at a 30 second on/30 second off interval, driving the clock line of the 4017. The first output pin of the 4017 could then drive the second NE555 with a 3 second on/3second off interval. Effectively sending a '5' every ten minutes in QRSS 3 second dots. The '5' being from the call sign of VK5. My call sign being VK5FNET. But thats a job for another time, but would be nice to know what folks think...

So, thoughts on work to be this weekend;

  • Get any antenna up

  • Get a length of RG-213 terminated with PL259 connectors

  • Blow the dust of my 4:1 balun I made some time back and check the connectors out

  • Modify the 80m DC RX to run on 10m

  • Patch up some audio cable for the DCRx to peecee sound card

  • Work out how to capture images or do screen dumps from glfer

  • Announce it...

Doesn't sound like much on 'paper', but on top of the domestic chores should be a busy weekend.



Tuesday, November 10, 2009

10 meters

On the Knights QRSS mail list theres been talk of activating more HF bands. Specifically 10 and 15 meters. There issues with activating 40 meters as there are access issues for non advance licences in the US and band plan issues across Europe. Not 100% sure how 40 meters is carved up elsewhere, but in Australia, Foundation, Standard and Advance all have access from 7.000-7.300MHz.

There have been a couple of contests on 10 meters with some success. This has lead to conversations on list to start putting SDR receivers and QRSS transmitters on 10 meters. The 100Hz QRSS band is 28.188,000 - 28.188,100 MHz. Folks have used other portions of the 10 meter band, around 28.322MHz if I remember rightly. Which seems to be around the QRP and QRO un-manned beacons.

Nick, VK1AA who is shipping the G80, G40, G2030, and G5 Genesis radios, has put up an offer to send out a batch of crystals on 28.188 MHz to folks free. So long as they get a MEPT or receiver up on the air for QRSS. I shot off an email straight away and am still patiently waiting for it in the mail.

I have started mods to the W1AW NE602/LM386 direct conversion receiver I build up for 80 meters. Needs rework on the band pass filter and local oscillator. Should be fun!