Well, the ball is now rolling. Just has the web site and mail list all sorted and we've put up a date for the first social meeting of the Adelaide Perl Mongers. Alternatively known as AdelaidePM.
We will start ariving around 5:30pm on Friday the 22nd of January at The Exeter on Rundle Street. We will most likely filter out to the back of the "beer garden" to find a coulpe of tables. Perhaps we can head out for food afterwards. See you there.
Thursday, January 07, 2010
Wednesday, December 30, 2009
One 8 step sequencer running on the bench
I spent a bit too much time googling for synth music and sequencers over the last few days. I had a lot of fun just reading about folks projects and how they built up various kits or designed from scratch different arrangements. I have not really spent much time working with 4000 series or 7400 series ICs in the last ten years. Well not since first year Uni to be honest. That was a long time ago and my memory for truth tables is long forgotten.
So, I almost cheated but finding the friendliest schematic I could find and trying to build that up. You know how it goes, adapting part of this circuit as a stage one of your project. Well I had a few problems. My 4017 wasn't behaving at all! I spent several hours on the bench trying to figure out why I couldn't get the thing to behave. The first problem was that I missed a ground connection on pin 12, eventually running a bypass cap to the reset pin before it settled down and started to do the right thing. But the first LED wasn't behaving itself at all ...
Some further testing revealed that the LED in the first position was a flashing LED! So its now in its own draw, in the component cabinet. The 555 was a whole lot easier to work with and was pretty much doing what it was supposed to from assembly. The potentiometer has a dead spot right at the fast end of oscillator, so may need to swap the wires on the pads, or get a new 1megaohm 'pot'.
I will say that after having the 'friendly' schematic, I did change most the resistor values, add a few extra capacitors and lay it up differently on the plug-in breadboard. Its not a new circuit, but I learned a lot, mainly how to trouble shoot this little thing.
So what have I achieved here? More motivation to tinker in the shed/shack on the plug-in breadboard and play around with the circuit. Getting things working build up the motivation to do more. I have a tall ladder before me. I'm aiming to make the rungs nice a close together. Easier to climb that way ;)
Anyhow, happy homebrewing to all!
72,
Kim - VK5FNET
So, I almost cheated but finding the friendliest schematic I could find and trying to build that up. You know how it goes, adapting part of this circuit as a stage one of your project. Well I had a few problems. My 4017 wasn't behaving at all! I spent several hours on the bench trying to figure out why I couldn't get the thing to behave. The first problem was that I missed a ground connection on pin 12, eventually running a bypass cap to the reset pin before it settled down and started to do the right thing. But the first LED wasn't behaving itself at all ...
Some further testing revealed that the LED in the first position was a flashing LED! So its now in its own draw, in the component cabinet. The 555 was a whole lot easier to work with and was pretty much doing what it was supposed to from assembly. The potentiometer has a dead spot right at the fast end of oscillator, so may need to swap the wires on the pads, or get a new 1megaohm 'pot'.
I will say that after having the 'friendly' schematic, I did change most the resistor values, add a few extra capacitors and lay it up differently on the plug-in breadboard. Its not a new circuit, but I learned a lot, mainly how to trouble shoot this little thing.
So what have I achieved here? More motivation to tinker in the shed/shack on the plug-in breadboard and play around with the circuit. Getting things working build up the motivation to do more. I have a tall ladder before me. I'm aiming to make the rungs nice a close together. Easier to climb that way ;)
Anyhow, happy homebrewing to all!
72,
Kim - VK5FNET
Monday, December 28, 2009
one dual rail 12V PSU on the bench and working
Spent a couple of hours researching and then building, testing/destroying, then researching and re-engineering a dual rail power supply for +12 volts & -12 volts.
Not sure what kicked it off, but I am kind of over my 10 meter QRSS receiver not working. I was looking at a ham radio blog, found a video of NE555 and 4017 based synth sequencer. Down the rabbit hole I went reading dozens of web pages, until finally finding the coolest sequencer I've ever seen!
On the Natural Rythm Music site I found a 16 step rotary analog sequencer. It is a visually amazing device, certainly feels more intuitive than you regular 4 blocks of 4 linear sequencer. The builder has a great presentation style and can put together some cool tracks.
This discovery then in turn inspired more and more reading until I found some basic building blocks. Everything seemed to need a dual rail power supply, so I though I should start there. Some web searching, followed by checking a couple of different editions of the ARRL handbook led to a simple dual rail regulated supply. I carefully noted down the schematic, made a parts list and marched off to the shed/shack to build.
Stepping back a ways, I purchased for two dollars, a two amp twelve volt power supply at the radio club meeting. I was a bit disappointed that it didn't work, but put it aside for a rainy days hacking I suppose its the risk you take when you buy gear from a deceased estate, no real history on the item. So yesterday was that day, except it was 32c, no rain and no wind. Makes the shack a little warm.
I amassed all the parts, dissected the old power supply, noted the two 10,000uf 24 volt electrolytic capacitors and carefully discharged then with a long screw driver... the spark was impressive for a power supply that had been unplugged and idle for six months. Note to self, be careful around these caps!
Spent a while working out the arrangement on tag strip, then manhattan style, but didn't find a nice way to mount everthing in the space available. Got a coffee then came back with the lost thoughts of some veroboard of yore...
Found the vero board and worked out a layout on the board from the schematic. Assembled it, checked it twice. Carefully hooked everything up and turned on the power. Everything looked Ok until the LM7812 regulator launched a small part of itself into orbit!
Ok, this wasn't part of the plan! Turned everything off, disconnected everything and started the autopsy. Everything was correct according the schematic. So I checked the schematic against the original. Sure enough the pin out of the LM7812 was wrong and had exchanged the ground and incoming unregulated power line, pins 1 and 2. No wonder it went FIZZ POP!
I downloaded the data sheets, just to be sure. Who would have thought that the LM7812 and the LM7912 would have different pin outs? I mean really?!?!?
Anyhow, I spent about an hour looking for a replacement regulator. Almost despondent that I'd never found one, I happened to find a little plastic draw that had been missing out of the component cabinet. Interestingly I must have put it aside when I first looked at the power supply and thought about reworking it as a regulated unit for 12 volts for my 2 meter radio.
Anyhow, it all went together more easily the second time and it passed the smoke test the second time, keeping the smoke on the inside! Along with providing 11.99 volts and -12.01 volts. The simple test load this time was a pair of 12 volt 20 milli amp four inch fans from a peecee power supply.
So, now to find all the parts for an audio VCO for tone generation, an LFO for effects, mixer for multiple channels, various high and low pass filters and an amplifier... The aim is that all of these will be building blocks for test equipment for RF down the track. Cunning plan huh?
Not sure what kicked it off, but I am kind of over my 10 meter QRSS receiver not working. I was looking at a ham radio blog, found a video of NE555 and 4017 based synth sequencer. Down the rabbit hole I went reading dozens of web pages, until finally finding the coolest sequencer I've ever seen!
On the Natural Rythm Music site I found a 16 step rotary analog sequencer. It is a visually amazing device, certainly feels more intuitive than you regular 4 blocks of 4 linear sequencer. The builder has a great presentation style and can put together some cool tracks.
This discovery then in turn inspired more and more reading until I found some basic building blocks. Everything seemed to need a dual rail power supply, so I though I should start there. Some web searching, followed by checking a couple of different editions of the ARRL handbook led to a simple dual rail regulated supply. I carefully noted down the schematic, made a parts list and marched off to the shed/shack to build.
Stepping back a ways, I purchased for two dollars, a two amp twelve volt power supply at the radio club meeting. I was a bit disappointed that it didn't work, but put it aside for a rainy days hacking I suppose its the risk you take when you buy gear from a deceased estate, no real history on the item. So yesterday was that day, except it was 32c, no rain and no wind. Makes the shack a little warm.
I amassed all the parts, dissected the old power supply, noted the two 10,000uf 24 volt electrolytic capacitors and carefully discharged then with a long screw driver... the spark was impressive for a power supply that had been unplugged and idle for six months. Note to self, be careful around these caps!
Spent a while working out the arrangement on tag strip, then manhattan style, but didn't find a nice way to mount everthing in the space available. Got a coffee then came back with the lost thoughts of some veroboard of yore...
Found the vero board and worked out a layout on the board from the schematic. Assembled it, checked it twice. Carefully hooked everything up and turned on the power. Everything looked Ok until the LM7812 regulator launched a small part of itself into orbit!
Ok, this wasn't part of the plan! Turned everything off, disconnected everything and started the autopsy. Everything was correct according the schematic. So I checked the schematic against the original. Sure enough the pin out of the LM7812 was wrong and had exchanged the ground and incoming unregulated power line, pins 1 and 2. No wonder it went FIZZ POP!
I downloaded the data sheets, just to be sure. Who would have thought that the LM7812 and the LM7912 would have different pin outs? I mean really?!?!?
Anyhow, I spent about an hour looking for a replacement regulator. Almost despondent that I'd never found one, I happened to find a little plastic draw that had been missing out of the component cabinet. Interestingly I must have put it aside when I first looked at the power supply and thought about reworking it as a regulated unit for 12 volts for my 2 meter radio.
Anyhow, it all went together more easily the second time and it passed the smoke test the second time, keeping the smoke on the inside! Along with providing 11.99 volts and -12.01 volts. The simple test load this time was a pair of 12 volt 20 milli amp four inch fans from a peecee power supply.
So, now to find all the parts for an audio VCO for tone generation, an LFO for effects, mixer for multiple channels, various high and low pass filters and an amplifier... The aim is that all of these will be building blocks for test equipment for RF down the track. Cunning plan huh?
Monday, December 07, 2009
MTB on the road
I spent some time over the weekend working on the mountain bike I picked up. The complete bike is less than half the weight of my old MTB! Its all aluminium, with the inch wide double walled with eyelets. Currently setup as a single speed, about 70 gear inches. Seems a good balance for pootling around the small hills here. Will fit road tyres at some point in time. Looking at fitting my rack this coming weekend. Then lay up all the gear for a short tour.
VK band plan
Was doing a bit of reading to confirm the frequency range for 15 meters to think through the IF article in this months AR magazine. So 15 meters covers; 21.000 - 21.450 MHz. I have a hand full of 4MHz and 25MHz crystals.
While I was reading through the band plan, I found something new, and entry for 2200 meters. But what grabbed my attention even more was that there was a mention of QRSS;
137.6 - 137.8 kHz Slow CW modes, e.g. QRSS
While I was reading through the band plan, I found something new, and entry for 2200 meters. But what grabbed my attention even more was that there was a mention of QRSS;
137.6 - 137.8 kHz Slow CW modes, e.g. QRSS
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.
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.
72,
Kim - VK5FNET
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.
72,
Kim - VK5FNET
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.
http://www.xent.com/pipermail/fork/Week-of-Mon-20091109/054578.html
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.
http://www.xent.com/pipermail/fork/Week-of-Mon-20091109/054578.html
Tuesday, November 17, 2009
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...
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 =)
72's
Kim - VK5FNET
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 =)
72's
Kim - VK5FNET
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 =).
72's
Kim - VK5FNET
72's
Kim - VK5FNET
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.
72's
Kim - VK5FNET
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.
72's
Kim - VK5FNET
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