Friday, April 29, 2011

Mystery station Ozyradio broadcasting on 5050kHz

Screen shot 2011 04 30 at 3 13 40 PMStephen, VK2BLQ, mentioned a station he'd noticed on shortwave at 5050 kHz.

When I started listening, the station was simply playing a short list of music with time calls. There was no station identification. Now I'm noticing some short spoken word segments some of which sound like they might be of a religious nature - sort of self help style. Others including "moneymaking moments, from the money maker", whatever that is.

DXing.info has a mention of the station, as does Shortwave Central.

People involved seem to be Ian Baxter, who responded to a QSL request from the US; Craig Morris, who seems responsible for the transmission and wrote "Been on from 5pm 3/4/11 - 300 watts NVIS Dipole, Station Playlist, Breakaway Broadcast & it sounds really good."; and Craig Allen, who holds the VKD963 license according to the ACMA register of Radiocommunications License.

License

They are transmitting from the west of Sydney:

View Larger Map

Today I notice they are saying "if you like what you hear" you can email them. I've done this and asked what they intend for the station.

Update from Craig Allen:

Hi Peter.

At this stage we are still testing and were building a new antenna for 5050khz and 2355khz in the long term the station will be middle of the road music, news & radio programs but we will be fully automated.
Thanks

Craig Allen

Station Manager

Update from Craig Morris:

so is this a new commercial station? No

What audience are you chasing? Anyone that can hear it !

I wrote back asking if it's a religious station. Craig replied:

"Hi Peter,

Were a new shortwave station in Sydney.Our frequency's are 2355khz,
3210khz and 5050khz.

At this stage we are still testing and setting up our TX site. At this
stage we are playing music etc and selling air time.

Thanks

Craig Allen

Owner"

So Craig Allen is now the owner and this kind of suggests it is commercial.

I see that Craig has a registered business name "Ozy Radio" and he's registered OZYRADIO.COM although it's still parked at this point.

There's a Facebook group.

Update: It's religious.

Well, the cat's out of the bag. The programming has now switched to religious content.

I'm currently in Canberra and can hear 5050kHz peaking at 42dBuV quite clearly on a portable radio (Tecsun PL-310) with its whip antenna.

Thursday, April 28, 2011

Homebrew 80m transceiver with DSB Tx and DC Rx

After we built homebrew 80m receivers to listen to the WIA broadcast, the challenge has been extended to a transceiver using a 3.58MHz ceramic resonator. Mine is just starting to work:



My thanks to Patrick, VK2PN who lives not far from me and agreed to have a contact and give me some feedback. I can hear him quite well on the direct conversion receiver but I think there's a problem with my audio at the moment. Quite possibly it's some sort of rf instability - given the ratty construction so far.

The design has an oscillator using a ceramic resonator that is shared between the direct conversion receiver (classic NE602 design), and the transmitter which uses a TUF-1 balanced mixer followed by two gain stages before an IRF-510 final.

An encouraging start, but lots to do to make it a viable transceiver.

Saturday, April 23, 2011

Bid history of a $1 start ebay auction

I've just sold a nice, but in recent years un-used, short wave radio on ebay. My practice is to start at $1 which tends to garner a bunch of bids early on. The theory is that this makes other bidders pay attention and increase the chance of a bit of a bidding war.

Here's a graph of the price bids vs time.

Price graph

The radio sold for $565 and $100 of that was in the last 60 seconds.

I often see items with a starting price at a good price but with zero bids at close presumably because bidders are worried that if no one else is bidding, the item isn't worth it for unknown reasons.

Wednesday, April 20, 2011

Software defined radio repeater system talk

QueenA great lecture night at the Manly Warringah Radio Society, with the Queen looking on with a knowing smile (I bet she understands I/Q demodulators).

Andrew Gilbett, VK2XAG, gave a presentation on his dissertation on using software defined radio for a repeater system including how this might be scaled up to a "repeater hotel" where a single SDR might implement multiple repeaters on different frequencies.

Andrew talked through convolution, gausian minimum shift keying (GMSK), which is used in GSM and DStar, and how all this is easily done in software.

For me, the hi-light was seeing GNU Radio in action using GNU Radio Companion (grc). Although GNU Radio can be used with a Linux PC's audio I/O, Andrew brought along an Ettus USRP (Universal Software Radio Peripheral) for the demonstration.

Gnu Radio

For the demo an antenna was attached to the transmit output connector, the receiver was simply the un-terminated socket, Andrew then used a VHF transceiver to talk and whistle while we watched the FFT and waveform on the live displays in GNU Radio Companion.

I rushed home to my Ubuntu 11.04 machine, installed GNU Radio, but it doesn't currently have GRC in there so I grabbed the source from the git repository and built using instructions here and here. (There are quite a few dependancies to be satisfied before grc will build).

Thanks to the organisers and thanks to Andrew for an excellent presentation.

Saturday, April 16, 2011

Amateur Radio NSW Annual General Meeting

Despite steady rain there was a good turnout at Dural for the ARNSW AGM today.

ARNSW AGM

Proceedings were well run and efficient and we were honoured to have WIA president Michael Owen at the meeting.

Michael OwenMichael talked about the current state of Amateur Radio and how the Foundation license has been successful in reversing the decline in numbers of hams. The decline has been seen in other countries more severely than here so things are looking up.

We heard some of Michael's experiences in Japan where he was when the earthquake struck and it was great to meet and have a talk about ham radio and how we fit in to the world wide regulatory scheme of things.

Monday, April 11, 2011

Why Malcolm Turnbull is wrong about the need for the National Broadband Network (NBN)

Nbnco logoShadow Communications Minister, Malcolm Turnbull, has been tasked by leader Tony Abbott to "demolish" the government's National Broadband Network. On ABC 24's "The Drum" on Monday he accused futurist Mark Pesce of drinking "the cool-aid" on the NBN, presumably a reference to Apple fans who line up to buy the next product without question because it's sure to be cool.

Malcolm argues that there aren't applications for this broadband in the average Australian home. Further, ABC 4Corners on Monday night found it hard to find households which had even bothered to take up a free offer to be connected to the NBN in a trial area.

But they're wrong, it's a "chicken and egg" problem. Businesses that could build their products on top of a high speed network will not invest and may not even imagine new products if the network isn't there.

We laughed when computers started including "postage stamp" sized video in their "multi-media" applications. Now we expect full High Definition playback on a tablet with 10 hour battery life. (That didn't take long).

Our media consumption devices; be they phones, tablets, networked televisions or even desktop computers; are already constrained by internet speed. This bottleneck is only going to get more constrained in the future.

Music has made the transition to digital in just seven years. The Apple iTunes store launched in 2003 and is the number one music vendor in the US. Last year the 10 billionth song was downloaded.

Books are well on the way to transitioning with the worlds biggest book seller, Amazon, selling more electronic than physical books by June 2010. Electronic books sales are set to "hockey stick" up due to the availability and popularity of tablet readers such as the Kindle and iPad.

Movies should now be being consumed "on demand" but a combination of poor title availability, high bandwidth cost, and again low broadband speeds are holding it back.

Physical music, video and book shops are starting to disappear, and this trend will continue.

So, even today, Australia's sub-standard broadband is holding back the average media consumers access to media, although they may not realise it. It's like when you first listen to a really great HiFi system, consumers don't appreciate what they're missing out on until they try it.

3D video potentially demands double the required download speed, and that's just the start.

Avatar director, James Cameron, is already looking beyond 3D and has been experimenting with frame rates much higher than the 24 frames per second that we view now to 48, 60 or even higher rates. These high rates produce an "enhanced sense of detail" and lead to a more immersive, realistic experience.

Even though the eye and brain paper over the missing frames so that we don't perceive flicker, this all falls apart if the subject motion is fast or the camera pans even moderately. Peter Jackson is currently filming The Hobbit at 48 fps.

Along with the doubling of data for 3D, doubling it again for high frame rate, there is another technology, waiting in the wings, that can easily require three times throughput on top.

Googles speedI can imagine a quadrupling of bandwidth to provide High Dynamic Range (HDR) imagery as well.

One of the example applications of a true broadband network is the ability to have a remote medical video conference. A two, or more, way high definition video conference in 3D at a frame rate of 48 or more frames per second again multiplies the broadband requirements. Doctors need to see the wound, observe the operation, sense the mental illness in full fidelity.

Malcolm Turnbull's argument that there aren't the applications for extra bandwidth shows a at least a lack of imagination, but I suspect it's really mis-direction.

Commercial carriers had a go at a broadband roll-out in the 1990s. Both Telstra and Optus rapidly strung out duplicate cables hanging below power lines in a few of the most densely populated areas and then just as suddenly stopped. In many streets those cables are starting to visibly fall apart.

The rest of the population is at the mercy of ADSL connections which, while amazing in the bandwidth they can push over copper wire, suffer a similar problem to Malcolm's other panacea - wireless, in that they share bandwidth amongst neighbours. ADSL works well if you only a few kilometres from the exchange, with few others using it, but it degrades quickly further out and if the neighbours really get into it.

An optical fibre network that reaches into homes is a key piece of infrastructure for the nation. Malcolm Turnbull knows, better than most, that as we head in to a world affected by climate change resulting from humans polluting the atmosphere with carbon, our broadband network will be as important as rail, roads, and hydro.

As the price of oil rises, from factors including: unrest in the middle east, peak oil, and the tax on carbon pollution, the ability for Australians to work and do business remotely may be an important factor in maintaining our competitiveness as a nation.

Update Thanks for all the comments and to the ABC Technology site which has picked up this comment and published it here.

Sunday, April 10, 2011

Getting started with HF Packet Radio

Shack glowI'm enjoying some time off between jobs at the moment. When I get up in the morning, it's as if a mystical glow draws me to the shack.

My electronics and radio room is very small - I have to slide in sideways to fit in the door. It's tucked behind the television in the lounge room.

The first projects have been to route antenna coaxes from other parts of the house in through the ceiling of the shack. I now have 80m, a half sized G5RV and 2m all going in there.

The next project was to get a PacComm TNC-320, which I purchased at the last "Trash and Treasure", working. It's been a bit of a struggle, so I thought I'd record these notes for others.

There's a lot of material out there about packet radio, but it's often very detailed and fails to answer the "obvious" first questions.

One problem for me is that while the TNC (Terminal Node Controller or modem) came with a quick reference card, the manual is lost and PacComm don't seem to put them on their web site.

I found the wiring required for a cable to my Icom radio's accessory socket here.

Tnc 320To get started I'm using a serial USB adapter (with a gender switcher) and the unix minicom serial terminal software.

There is frequent activity on 40m but I couldn't decode it. Patrick, VK2PN gave me some clues about the baud rate I should expect (300 baud) but still no luck. Finally doing a RESET on the TNC seemed to fix whatever brain scrambling it had suffered and it started decoding.

Now I'm seeing traffic with the dial set to 7037.17 LSB at 300 baud. Stations I've seen so far include VK2RX, VK4ALN-2, VK2WL, and VK2TT.

Up at 7039.15 I can see VK2AAB and VK2SLM who seem to be transferring a jpeg image with lots of re-tries - not too interesting to watch!

Minicom

I have successfully connected to another station, so I know it works. Unfortunately there was no-one there and so I stumbled around for a while trying to figure out how to break out of the connection. (I even tried +++ like the old days with Hayes modems {the trick is Control-C}).

TNCs have a huge command set. Here are the ones I've used so far:

  • reset - to return to factory settings
  • mycall VK2TPM - to set your call sign (replace VK2TPM with yours!)
  • monitor on - display traffic (it was on by default)
  • connect VK2XXX - to connect to another station, (to get back to the command prompt use ^C)
  • disconnect
  • display - show all settings
  • mheard - display a list of all stations heard by the TNC
  • mhclear - clear the list of heard stations


I failed to find any friendly packet software for Linux so I've switched back to Windows and am currently using WinPack v6.8. It adds a little to the terminal interface but I'm hunting for something better.

The TNC-320 looks to have some interesting built-in capabilities including a mailbox store, more investigation is required.

Having used PSK31 on 20m for digital keyboard to keyboard chat, which works really well and is easier to tune thanks to the waterfall display, I'm not sure that we still need TNCs but I'll have a play around and see how it goes on 40m.

Friday, April 08, 2011

Preview of Ubuntu 11.04 (beta 1)

UbuntuMy favourite operating system is MacOS X, my second favourite is Ubuntu Linux.

MacOS X has been pretty stable in recent years and Ubuntu, which is clearly influenced by Apple's UI, has been getting dramatically better each year.

The Gnome desktop does work rather like Microsoft Windows and with 11.04 it looks like the MacOS influence is now coming to the fore.

The Unity desktop removes the bottom bar, adds a top bar that is cleverly shared between being global and the current application menu if it is maximised. On the left of the screen is a dock ("Unity bar") for launching applications. Top left is the Ubuntu icon where you can search for things to run, kind of like the Mac's Spotlight.

The dock is of Apple standard with lovely drag-and-drop rearrangement.

I feel like some things I use are now hidden, items in the old Preferences and Administration menus, for example - but they're all still there if you know what to search for. Update: it turns out preferences are a menu item under the "power" menu at the top right of the screen, not a place I guessed.

The top menu bar, which becomes an application's menu bar when it's maximised, is a masterstroke. It's better than what Apple does. This works in some applications but not others.

The dock is good and the popup windows, whatever you call them, during search are quick and nice looking.

Speed

After years of every upgrade of Windows getting slower (Until Windows 7) and require faster computers, it's been great to see both Apple and Ubuntu Linux get faster with each release - or at least have graphics intensive features be optional.

This version of Ubuntu feels really snappy to use and boots even faster than the previous two, that were a great improvement on the past themselves. Even re-connection to WiFi seems faster than before.

The spaces implementation is fantastic and there's an Expose style "Workspace Switcher" view that works really fast too.

Installation

I installed two ways, first using the built-in updater to go from 10.10 and second using a CD to update. The first update took about three hours, the second was maybe an hour (I left it running). Both upgrades went smoothly and kept my settings.

The estimated upgrade time varies wildly during the built-in update but eventually settles down.

After the Beta 1 install, I managed to find Software Updater and applied all the outstanding updates, so my experience is post beta 1.

Issues

Despite some bad press from other early reviewers, I'm finding this Ubuntu very good given there's about three weeks to go.

I'm seeing some minor keyboard focus issues with the dark windows that pop up for searching, (I notice that these windows don't appear in remote desktop (VNC) views of the screen so they must be cutting some graphic corners here).

The "Ubuntu Software Center" told me it needed to repair some files a couple of times but nothing bad happened.

Frustratingly, I can't see how to customise the launchers in the dock, right clicking doesn't show properties, consequently I have some broken launchers that I don't know how to fix.

Summary

Ubuntu 11.04 looks to me to be really solid. The extra screen real estate and the decision to put the dock on the side will work well with wide and small screens. The use of larger, presumably finger sized, elements means that this UI could work OK on a tablet in the future too.

The big change to Unity, plus some sensible default application changes (like LibreOffice), I found refreshing rather than a blocker. If I really can't locate what I want Gnome can be installed if required.

Great stuff Canonical and the Ubuntu team.

Thursday, April 07, 2011

Antenna porn. A tribute to the BBC's 648kHz service.

Tribute to BBC 648 kHz Orfordness - The Enthusiast's Version from Jonathan Marks on Vimeo.



The budget cuts to the BBC are obvious on-air even from here. This video is an interview with an engineer at an amazing transmission site that was used for beaming radio into Europe from a salt marsh with very high power at an ex radar site.

Is running co-ax up the mast, with the mast base grounded and the feed point at the top, common?

Nice glimpses of an old Optimod in there too. It's great to see that the engineers salvaged some valves and coupling coils for a display, it won't be long until these beautiful components are very rare.

Here's a big antenna being demolished:



And another.



Thanks to mate Nigel for these.

Wednesday, April 06, 2011

Re-joined the local Manly Warringah Radio Society

I have a few weeks off and last night I went to the social meeting of the local radio club, the Manly Warringah Radio Society.

Since my last visit they've moved into an excellent new venue in a Guide hall that is currently not used. It's a great radio location with very low noise - I marvelled at the quiet on 20m and 80m compared to my home.

VK2MB station equipment is securely stored in a nice cupboard and well laid out and labeled for ease of use.

Mwrs

The move also prompted a big purge of the masses of junk that had built up at the old club house over the years.

The club has a few regular nets, one at 6:30am on 3590KHz and another at 8:00am on 3585KHz. I have been listening for a few days and called in to the 8am net this morning and was welcomed by the group. It's one of those nets where the participants are so familiar with each other that they know who's who just by a brief transmission.

Weekly meetings are a bit above my current time budget but I'll try to participate a bit more. I heard someone commenting on not having enough time available - as he's retired you know!

Sunday, April 03, 2011

Bush "walker" pocket DAB+ receiver

Bush frontI'm enthusiastic about the DAB+ digital radio system but the receivers still disappoint. Bad user interface, high power consumption and bugs (I'm looking at you Sangean...).

This radio works pretty well, battery life is said to be ten hours, which is terrible compared to my old Sony pocket analog receiver, but good compared to any other DAB+ radio I've tried.

Naturally the headphone cord is used as the antenna and despite the signal strength meter showing full strength I get decode interruptions around the house. Perhaps this is due to interference rather than low signal.

Stations are shown in alphabetical order rather than frequency so sometimes stations you'd expect to be grouped end up far apart. There's a nifty "favourites" feature that lets you skip around your favourite stations

I purchased the Bush Walker BPR07DAB - Handheld DAB+ Radio through the Telstra Bigpond online store for $79, which seemed like a good price as the radio is advertised at $100 or more elsewhere. Delivery seemed a bit steep, at $9.95 but when the box arrived I could see why:

Bush box 2

Amusingly the little radio in its packaging was simply rattling around inside the large box without padding, very strange.

Saturday, April 02, 2011

Emtech ZM-2 Z Match antenna tuner review

Just received a ZM-2 QRP antenna tuner of the Z-Match design that I ordered from Emtech. It seems able to match a random wire with ease on multiple bands. In the video below I threw about 10m of wire into a tree and was able to tune up on 20m, 40m and even 80m.



Tuning is quite sharp and for transmit there is a built-in SWR bridge with an LED indicator that you tune to extinguish.

It's a compact unit, a good companion for the FT-817, and works very well. Rated at 15W maximum it's perfect for QRP operation.

Mine took about a month to arrive here in Sydney and even came with handy hints on how to get into heaven!