Tuesday, December 4, 2012
Oh, found a nice resource; http://www.vax.si/
Sunday, November 11, 2012
Once in a lifetime experience for theSkyNet citizen scientist.
I'll be putting up a series of posts here shortly about my trip.
Wednesday, October 24, 2012
The is itinerary coming together. So there will be a little bit of driving. About 17 hours round trip. So what is it all about? Its all about going to the SKA, here;
View Larger Map
And talking to the scientists and engineers! I have a few questions now, mostly about the data, lets start with these;
How much of a difference it makes to put the array in a relatively isolated area like Murchinson?
Whats the comparitive S/N numbers?
How many Antennas, LNA and receivers?
How are they comapring the data from those receivers?
Whats the effective gain of a single array, vesus the whole array versus a single Antennas, LNA and receiver?
Is this pahsed to drive direction?
How to shuffle that volume data around?
How is the data going to be processed?
How is the data going to be used?
How is the data going to be stored for reuse?
There are so many pieces of the puzzle that I haven't seen yet. You can see this is only scratching the surface!
I suppose the big question for TheSkyNet crunching public is how can we help? =D
Tuesday, October 23, 2012
While I have been busy posting VK5JST Antenna Analyser kits for the HAM radio club, Erich has been busy circuit bending!
Its a devious hack! I dare say very unsupported by the kits designer Jim VK5TR/VK5JST.
But as Erich says "if you can't modify the software in the box, you don't own it".
I wonder what other kinds of hacks one can build up from the kit?
Monday, October 15, 2012
So there will be a few firsts for me. I have been to see the Parkes radio telescope last year on a trip from Tasmania to Southern Queensland. I had vague recollections of seeing it as a kid on trips through the area, but its *big*. Much bigger than I remembered. The Parkes telescope inspired my reading and interest in robotics. Its one of the reasons that I got into computers and networking. Its also part of the journey that got me into Amateur Radio.
Well, the wheels have been in motion for a while now. Yesterday planning began for a trip to see the SKA! More details as they become available.
In the mean time, if you are interesting in big things, check out this video about the volume of data, comms and computing challenges the SKA faces.
Friday, October 5, 2012
Thursday, September 20, 2012
I have been reading the background on the array installation. Everything about the build is fascinating. They've taken photos of everything from hardware being built and installed to local flora and fauna =)
Read more on the MWA Student Army blog.
So here are some photos of the site, some the team and hows the serenity?
Tuesday, July 31, 2012
sharedopts="--verbose --diff=none --getcontents --ignore-missing-release --ignore-release-gpg --arch $archs --allow-dist-rename --source"
echo "std dists"
/usr/bin/debmirror --method=http \
--dist $dists \
--host $host \
--root $root \
echo "sec dists"
/usr/bin/debmirror --method=http \
--nocleanup $sharedopts \
--dist $secdists \
--host $host --root $secroot \
Saturday, July 14, 2012
/m means "mobile". Well its nearly mobile. I'm nearly finished painting the panels. Honest. Actually after I just cut this rust out...
The last couple of weekends have seen a few hours work each day on the FJ45. I've uncovered some more serious rust. However it will not be too hard to resolve. The fenders and other panels are 1mm steel sheet. I was given some advice "they are 1mm and solid enough and you can stick weld the panels easily." Well I gave it a go. Perhaps the rods I was using were wet or something, but it was a whole lot more difficult that I was expecting. Or I am just out of practice... Either way, I will cut out my repair and try again with a mig or oxy welder down at Lyns place. Just need to find some more 1mm steel and fold it up to the right shape.
In the mean time, you can see the 2 meter band antenna I've put on the front bar. There was an antenna mount there already, it just needed a little convincing with a file to accept the SO239 for the antenna base.
In the future I think I will acquire a pair of spring bases for the front bar and weld on a pair of antenna mounts, both on the left side.
I'm just waiting for my toes to defrost before I head out to do more work on the 45 =D
Monday, July 9, 2012
I've been meaning to deploy puppet or chef or something similar for some time. You know how things get, work gets busy, long commutes eat your soul and you don't have the head space to tinker much when you get home. Although on the last few week ends I have managed to get some quality time working on the ute (read mobile HAM radio platform).
So yesterday after getting that feeling that I've had enough ssh'ing to every server to install a package, I decided that it was indeed time to automate that kind of thing.
I first heard about salt at Linux.Conf.Au in Ballarat this year. A podcast was recommended to me about it. I have had at least two separate attempts to install it at home and one at work. As Salt and its dependencies are not in the Debian repo, it was install from source time. Well yesterday I twigged to the reason why the builds failed. You don't install the dependencies from the repos, you use the release tarballs. One of the dependencies relies of cython in the development repo and completely fails to build.
So here is the simplest install for Salt on Debian/Squeeze (note custom install destination);
apt-get install python-yaml cython python-m2crypto python-pycryptopp python2.6-dev
apt-get install libssl-dev swig python-sip-dev python-sip cableswig
tar -xzvf zeromq-2.2.0.tar.gz
tar -xzvf pyzmq-2.2.0.tar.gz
python setup.py configure --zmq=/usr/local/zeromq/
python setup.py build
python setup.py install
tar -xzvf pycrypto-2.6.tar.gz
python setup.py build
python setup.py install
mv master salt.tar.gz
tar -xzvf salt.tar.gz
python setup.py build
python setup.py install
Wednesday, June 6, 2012
Monday, April 30, 2012
Well I can only say, it isn't so. Today we hit a bit of a milestone. As I left the post office today it slowly dawned on me, "I just posted kit number 100!".
From the email response the feedback has been pretty good. Most people have been pretty happy with the completeness and quality of the kit. Sure we've had a few small hiccups, but we had them sorted pretty quickly. Our suppliers have been wonderful. Our kit packager, Wolf, has been wonderful. The AHARS committee has been nothing but supportive, helping out where ever they can in their busy lives.
So, we have a basic benchmark of twenty kits posted per month. In a years time, hopefully we will continue to see the VK5JST Aerial Analyser ship in similar numbers. This time next year I would hope we have a few more kits to offer too. Time will tell.
So one thing on my to do list, is to finish my Aerial Analyse kit before Winter ;)
73, Kim VK5FJ
Thursday, April 19, 2012
VM on KVM on a VLAN on a bridge interface on a bond interface across multiple NICs on Debian/Stable - Squeeze
* vlan - 802.1q, LACP, VLAN trunking
* ifenslave-2.6 - ethernet bonding or port-channels
* tcpdump - your friendly packet dumping program
So of course you will need to make sure your repository is pointed somewhere useful and run as root user;
apt-get install vlan ifenslave-2.6 bridge-utils
Also you need to make sure the kernel modules are loaded. I put them in /etc/modules so they are loaded at boot time;
# /etc/modules: kernel modules to load at boot time.
# This file contains the names of kernel modules that should be loaded
# at boot time, one per line. Lines beginning with "#" are ignored.
# Parameters can be specified after the module name.
Then we need to update the /etc/network/interfaces file;
iface eth0 inet manual
iface eth1 inet manual
iface eth2 inet manual
iface eth3 inet manual
iface bond0 inet manual
bond-slaves eth0 eth1 eth2 eth3
# 10.0.0.0/24 - VLAN 1000
iface br1000 inet static
Thats it! No really! You end up with the interfaces;
eth0, eth1, eth2, eth3, bond0, bond0.1000 and br1000.
The important difference to notice from other Linux distros is that Debian requires the following statement in the br1000 interface specification;
It quite simply doesn't plumb the bits through to the right interfaces with out it. I also moved the enslave statements back into the bond0 interface specification. Other wise the config is the same as described over at Networking in Ubuntu 12.04 LTS.
So you then use the bridge interface br1000 in virt-manager to plumb your VMs network onto the VLAN on the wire. Make sure you create the NIC device and select the right driver. I have been using virtio. Perhaps the e1000 could be used instead, but folks have suggested sticking with the virtio for latency reasons.
I had previously wrangled the bonding and setup the interfaces, with LACP with our good network folks. Note we use bond-mode 2. You may need to use a different mode, depending on how your switches are configured.
Remember to put add the DNS search and nameserver statements in your interfaces too.
I used tcpdump alot. Mostly like this;
tcpdump -i bond0 not port 1985
Removing the port 1985 drops all the switch chatter. So you can see what is actually coming in from other hosts. I also ran tcpdump on the bridge interface br1000 to see what traffic was going in and out. It too a while for me to realise that the bridge wasn't plumbing the VLAN to the bridge until is added the vlan-raw-device statement. I added it to see what would happen because I had nothing to lose and had to get the server back online so folks could get work done on the DEV server =) So there you have it. Hopefully this post will be useful to someone, I know it would save me a whole bunch of frustration ;)
This post is a beginning of a long journey no doubt.
It started some time early last year designing, quite specifically what we wanted to do when we replace our old servers.
In the design was a pair of machines that would run VMWare for a number of VMs that would replace a bunch of cron jobs, web apps on the old servers, plus a mountain of little things running on a collection of our desktops. These things are all production or new development and new UAT services that we have been working on for the last couple of years in between the deluge of day to day work.
So, we have build a DEV and a UAT machine. DEV is where we create new code and do the initial testing and deployment for new webapps and other tools. UAT is where we our users do testing on that new code. DEV, UAT and PRD, its a model used in the whole organisation, so its a good model as every one is used to it.
So over the last couple of months, I've been building these services, moving things from the old servers to the new. A couple of things popped up that we wanted to run on VMs to limit the damage if something internet facing is pwnd. Hey, it happens unfortunately. Being careful is the more responsible that cleaning up afterwards, IMHO ;)
So, VMWare simple wasn't a viable option, even thought cost isn't a factor because of our licensing arrangements. Latency is a huge problem in all the VMWare server farms we have. High latency and web services is a massive turn off for casual web browsers and your customers/users hate to wait. So it was really the organisational limitations placed on VMWare that lead to its demise for our use. Its technical limitations also didn't help us. The storage and management interface are also limiting.
So we did our homework, spoke to lots of sysops and admins. KVM/QEMU is well supported on Debian/Stable, has all the tools packaged too. It has Linux native management interface, the biggest win really. We just don't do Windows Servers.
When installing the VMs I ran into that fun problem of now what network interface do you want to use? Arrggghh!
Time to re-learn all about bridges and plumbing VLANs around on top of the existing ethernet bonding setup. We bond four one gigabit NICs into a single bond0 interface and then have VLAN interfaces on top of that. Bridging added a whole new word of complexity!
I spent many hours reading up about how to do this. It seems it is not a common approach to run a VM on KVM on a VLAN on a bridge interface on a bond interface across multiple NICs.
It seems there is some doco out there about how to do this on Ubuntu 12.04, but it doesn't work on Debian/Stable (Squeeze).
So finally when I got this all working yesterday I had to document it and post it here on the blog so others can do the same and give some feed back.
Wednesday, March 21, 2012
I think I'd like to get a couple and start to get a working knowledge of vavle gear...
I made 27 contacts! Previously on the JMFD I made 9. This time I worked on and off for six hours, I made contacts on 80m, 40m and 20m. Made most the contacts on 20m.
Also on the weekend I had a QSO with F5PAU and ED4GUI. So I can add a few more DX contacts to the log.
I am really liking the Off Centre Fed Dipole. Although I expect that it is more to do with the height that its suspended at now. Its about 5-6 meters up with the ends folded back.
Saturday, March 10, 2012
I've been testing the dipole, attached to the boom, using c-clamps on the top of the Hills rotary clothes line. That way I can rotate the dipole to get the strongest signal. However rotating it didn't seem to produce much improvement in signal. So I lowered the mast and bolted it up about eight meters above ground level and about five meters above the shed.
I was running 50 watts in both locations. On the clothes line the SWR was 1.2:1. Then on the mast the SWR was around 1.1:1. However the signal strength of incoming stations wasn't much improved.
I tried making contacts for about two hours. The band was quite noisy, S7-S9. Around 0700 UTC the band cleared up locally to S2-S4 noise. Tuning around I heard JH2UZR calling CQ. However the local noise near JH2UZR made for a difficult contact. None the less we exchanged signal reports, 4x8 for JH2UZR and he gave me a 5x9.
Afterwards there was a pileup on 3W7W, Wayne in Vietnam. I had a couple of attempts to call back but he retired for the day. I had a couple of attempts to contact other stations heard, but the noise came right up.
One of these days I am going to have to figure out why everyone seem to hand out 5x9 even when it has been a difficult contact...
Anyhow, it was exciting getting a DX contact on 15 meters this afternoon =)