Saturday, June 27, 2009

DV Dongle Downer

A DV Dongle arrived in the post today - somewhat of a surprise as the online store of Waters and Stanton were showing it out of stock when I ordered it a few weeks back, and is still showing "Back Order" as I write this. I must have been lucky for once!

Anyway, the DV Dongle is a device that simply provides the hardware codec for AMBE, the digital audio compression standard currently used in the D-STAR DV mode. It is somewhat controversial, being a proprietary component of the otherwise open D-STAR spec. The DV Dongle isn't cheap, but it's the only product that I'm aware of that enables computer software to act as a D-STAR DV gateway to the network. Obviously, this has the upshot of allowing you to participate in D-STAR calls even when having a radio isn't too convenient (such as when I'm travelling).

A least that's the plan.

The DV Dongle fully supports the Mac, and indeed the supplied software to drive it "DV Tool" is a Java app, employing the Java audio framework, along with some native components to shuffle audio streams to and from the DV Dongle, connected to a USB port. In the installation instructions you are requested to download the latest serial drivers for the FTDI UDB-Serial bridge chipset. I had done this several weeks ago as I have other devices that use this chipset (including the Black Cat USB to CI-V interface). In any case, the software starts up and seemed to connect to the dongle hardware OK.

My problems began when trying the simple loopback audio tests with my Logitech headset (a recommended configuration). The software offers two loopback tests - one without needing the dongle (presumably just the Java audio stack), and one via the AMBE encoding/decoding hardware. My experience with either of these was not good - choppy sound with a distinct periodic transient (less than 0.5s I think), and a nasty lag. The lag with the dongle in the circuit is getting on for being between 2 and 3 seconds! In any case, the results are hardly broadcastable, and I believe I have a problem somewhere that is introducing enough latency that the audio streams are starved with the 0.5s period. I could also be sequential/blocking behaviour somewhere, where asynchronous behaviour is required. Anyway, at the moment I can only guess.

I've made a posting on the DV Dongle Yahoo discussion list, and so far I have been entreated to check that I am using the 1.6 Java stack (rather than 1.5 that apparently has issues). This has certainly been the case, though I have switched between 1.6 and 1.5 in a quest to find if that makes a difference - it did not.

So, hopefully some further ideas will come forth and I can experiment some more. I'm assuming that normal operation results in smooth/clear audio, and it looks like people are successfully using this on Macs - so I remain optimistic that this will turn out to be some irritating little piece of configuration that will eventually be a simple fix. Fingers crossed.

Sunday, June 21, 2009

D-WARP an idea for "contact agency software" for D-STAR

I was thinking a little about software that would make D-STAR even more interesting and convenient.

D-STAR provides relatively easy to use global communications through its gateway connections between repeaters. I've just been fooling around a little for the first time with gateway routing to some repeaters back in my old stomping grounds in the UK. This works rather nicely, and although I've not used IRLP, the setting up of routing seems less messy than what I've read is required for IRLP.

I don't know how many hams care about long-distance working, but it strikes me that it would be nice to be able to see which stations were on and interested in accepting non-local calls. To that end, I can image a sort of directory of D-STAR stations as a web application, which could show stations cartographically or in a tabular form. Maybe every station could indicate whether it was just "monitoring", "inviting calls" or "actively calling". It might also be nice if every station could offer a "synopsis" and perhaps keywords/tags indicating major interests of the operator. That might facilitate more engaging hook-ups/QSOs between hams who determine they might have similar interests. Clearly, the listings could allow linking through to other station details, such as QRZ, or a station web site.

A key feature of this facility might be to auto-tune/route an attached radio when a calling operator selects a station to call. Furthermore, it would be good if the status of both stations could be automatically updated when either or both stations transmit between them. This would indicate online that the stations are in QSO and are not awaiting a call (though of course other stations might want to join them). To that end, it might also be nice if such connections could indicate online the topic of a conversation (defaulting to "general") and whether others were actively invited to participate. Obviously, when parties sign-off, their status should revert to their original indication - it would be nice if this could happen automatically, but that might simply be a time-out; and of course the user should be able to do this with a single click.

As well as soliciting contacts and showing a global state of D-STAR stations in this fashion, it might also be nice if stations actively in a QSO could be offered a 'dashboard' showing all the contributing parties, and offering extra features such as 'quick email' or 'send file'. These features could be mediated by the central server (i.e. hiding the details of the end-points), and could also be 'unlocked' for a given user by issuing a single-use pin that one station would read to another over the air.

I'm still very new to D-STAR, but a service along these lines would seem to really augment the capabilities of the D-STAR network itself. I'd be very interested in feedback on these ideas, and although I doubt there are too many people reading this blog, I'll see what people think as I meet/talk with them.

Thursday, June 18, 2009

VisualQTH gets an airing

I demoed VisualQTH at the club this evening as part of a preparatory demo of the N1MM logging software by Dave Shipman VA7AM for the club field days (last w/e of June in the North Shore EMO, the club HQ).

We started the app up on the projector in the main meeting room - where we expect to receive visitors while the radios in the permanent club radio room are operating on a contest. Dave then made some entries into the N1MM logging software in the radio room, and these then appeared up on the display. So things went as expected :-)

Tuesday, June 16, 2009

First D-Star QSO, and more arcana

I had about an hour free today to see if yesterday's apparent successful round-trips to the ICM repeater would translate into an actual contact.

From my cursory understanding of routing configuration gleaned from various sources, I tried to cross-band on the repeater from my uplink port A to the 2m port C - I figured that fishing on 2m would most likely to find someone.

I tried a CQ call with
a few times and noticed a funny message "UR? VA7ICM A?" pop up when I unkeyed the mic.
Mmmm... I wonder what that message means, I thought. Maybe there's still something wrong with my routing/set up. I figured there would be something in the ID-1 manual on possible status/error messages, but on inspection... not a sausage. Icom are very light on documenting any operational aspects of the radio in the manual - it's mostly just buttons and menus that they care to comment on.

I then tried the following routing:
figuring that maybe this was an alternative way to address a port C (2m) downlink on the local repeater. This flashed up another message: "RPT?", which was equally indecipherable (though strongly suggested that it didn't like something in an RPT field).

After checking that in both cases, my call was still appearing in the Recently Heard list of the repeater on the web, I resolved to try the original routine config once again, an called once more with that setting. I just wandered back to my computer once again to check that the repeater had seen me, when suddenly for the first time there was a voice emerging from the ID-1's speaker, and I just heard my call from across the room.

The caller was Gord VE7FKY, who kindly responded to my call out through 2m. Apparently I was getting out the whole time, and what I considered (still do!) the odd "UR?" message is simply some indication that nobody has responded.

Gord was kind enough to enquire whether I had completed my gateway registration correctly, indicating that you have to complete at least one extra row of information in the "Personal Information" screen of the gateway registration - something I had not done. It turns out that this extra information is essential to having the gateway accept and route your calls across repeaters, and it occurs to me that this might be why the second form of routing mentioned above resulting in the "RPT?" message.

It's not super-clear during registration that this step is required - though in retrospect I do see it mentioned various web pages. It entails adding a single space into one "initial" field, and adding your lowercase callsign as a "pcname", and finally clicking a checkbox and a button to tell the gateway software to update that row in the registration record.

Having done this, I need to test a gateway routing again, and I'm wondering about simply retrying that second form to see if it is now working (routing out via the gateway, then back into the same repeater to another port).

I've resolved to really read about and understand what the various rows are in the "Personal Information" screen, and how you use them when (unlike me currently) you do have multiple D-Star radios.

Anyway, with my first QSO properly under my belt, I can now safely assume that all the components of my 23cm setup is working satisfactorily. I'd still like to test the VSWR of the Comet CYA 1216E sometime, especially as the ID-1 got pretty hot (enough to actually smell strongly of "new electronics"!) when transmitting on the nominal 10W power. That's probably quite normal, but it would be nice to be confident that the antenna system and feed line are in the best shape they should be. That's going to be another investment in shack gear though (there are only a few SWR meters capable of covering the 23cm band) and you get to pay a pretty penny for the privilege, so it might have to wait a while!

Aside from enjoying a little ragchewing on my newly commissioned toy, I'm gradually accreting an agenda for other things to play with on D-Star. The DD mode is a must-try sometime very soon, but I'm also reading about various tools that make use of the "spare" 1200 bps bandwidth in the DV mode (for text messaging and maybe other purposes - a BBS anyone?).

D-Star lift off!

OK, I just tested my set up into VA7ICM using the trick of setting the local gateway for RPT2 routing, but with the CQCQCQ UR Call. Everything works hunky-dory... at least I get back the error message from VA7ICM saying it can't find the call CQCQCQ.

So it looks like I'm in business, and more to the point that my handiwork in getting the yagi up and pointing in the general direction, with the feed line in good shape, is all OK.

I've tried both 10W and 1W (low power), and seem to have no problem being heard/understood by the repeater, at least for this minimal handshake. It would be cool if you could get the gateway to respond with a signal/quality metric, perhaps displaying this with your call sign in the available online logs (last heard lists), that way I could ascertain whether 1W is genuinely sufficient for reliable communication with the repeater, or whether it is borderline.


I've just tried VE7RAG, which is well off-axis of my beam, and still managed to wake up this repeater too on 1W! So, I'm a pretty happy bunny. When I get time I might see if I can wake up VE7VIC too. I very much doubt I can make it into that repeater as it lies some 61.33 statute miles to the SSW. This is well beyond the stated 20mi range claimed on the repeater. I don't know how this is computed, but it's noticeably less than the 40mi claimed for both VE7RAG and VA7ICM.

More D-Star learnings

Pete (AE5PL) replied to a few questions I posted up on the forum concerning some outstanding questions I had.

Two items of particular interest:
1. I had asked whether there was a way to test D-Star access into a repeater without bugging anyone for a radio check.
Pete said:
Sure, place CQCQCQ in URCALL, VA7ICM A in RPT1, and VA7ICM G in RPT2. You should see VA7ICM G respond back that it doesn't know CQCQCQ (you will see VA7ICM G show up on the front display).

... pretty handy!

2. I asked about gateway registration on repeaters, considering I had registered on one repeater but am likely to be using another for most activity. I was concerned as to whether you should be registered on the gateway you were actually going to be using as a 'home'. Pete's response was that you only need register on one gateway (and indeed should not be registered multiple times), and that registration on any one gateway is sufficient to use all gateways.

Considering I have yet to raise the admins of VA7ICM with this same question, I'm pretty glad my VE7RAG registration (which went through in under a day) will work anywhere.

Tomorrow I intend giving my ID-1 its first airing with an attempt to wake up the VA7ICM repeater in the manner described in (1). If I get any sign of life from the repeater on its port A, then I'll try a CQ call onto its 2m port to see if I can magic up a real QSO!

Sunday, June 14, 2009

23 cm beam to VA7ICM

My 23cm capability got real today (theoretically) with the addition of a real antenna to replace the indoor mobile antenna I had hooked up as a temporary measure. A Comet CYA 1216E is now gracing my tower, pointed in the general direction of the VA7ICM D-Star repeater in Surrey.

The rough direction to point was determined from the location of the repeater available on-line:
VA7ICM location

Using this information, I was able to plot a line between my QTH and VA7ICM using Google Earth, and ascertain the direction to point in according to visible landmarks:

As usual bumbling around up the tower was 'fun'. I especially like the bit where you are holding the antenna, with an awkward 42' of LMR-400 coiled out the back, and trying to get the U bolt/nuts aligned and tightened without slipping anything or dropping anything (least of all oneself).

Anyway, I survived :-), and in theory the antenna is aimed at the right spot for VA7ICM. In practice I may have to wait to find out if everything is working until I'm properly registered on VA7ICM and unregistered from VA7RAG (which I registered with before realising that VA7ICM is probably a better choice in terms of line of sight, even if its a little more distant). I've been waiting for a response from the VA7ICM admin for a few days, so hopefully something will be forthcoming soon.

Here are a few pictures of the new tower denizen:

Friday, June 12, 2009

More D-Star experimentation (and reading)

With the ID-1 hooked up to a temporary indoor antenna, I was hoping to hear some activity on one of the two local repeaters.

The closest repeater is only about 8.5 miles away, but Google Earth strongly suggests that its antenna is not line-of-sight from my QTH. Despite being at almost 1300', and the VE7RAG repeater being at 2700', the southern flank of Mount Fromme comes between the two locations and so this repeater is masked (though this might not necessarily be entirely 'fatal').

The next closest repeater is VA7ICM. As far as I can tell, this should be completely line of sight to my QTH. Google Earth seems to indicate this is the case, though an attempt to verify this with binoculars this afternoon was rather stymied by the haze caused by the hot weather and the results of the wildfire burning near Lilooet. Hopefully the air will clear soon and I can retry the exercise. This repeater lies some 18.3 miles to the SE, but really ought to be perfect given the LOS.

I have not yet tried to fire up either repeater yet, but leaving the ID-1 on for a few hours while surfing for information about how to 'drive' a D-Star rig I heard nothing. This isn't a huge surprise, and I suspect it's mostly likely because I'm on 23cm, the least popular D-Star band (though the one I'm interested in because of its novelty and also the high speed data mode). Also, I imagine my temporary indoor mobile vertical on a mag mount isn't going to perform terribly well - though I simply don't have any experience to draw on at this point as to whether it would be completely useless.

I have decided to erect a Comet CYA 1216E antenna and point it at VA7ICM if all goes well. I'll measure the likely length of required LMR-400 tomorrow - I'm told this will do as a feed line, though obviously it has fairly large losses at 23cm.

My research in how to actually use D-Star to initiate (route) a call has turned up some useful references. It appears that it is generally accepted that Icom's manuals are pretty woeful when it comes to edifying the new users in this regard, so most repeater groups have some sort of "getting you going" notes on the subject. Here's a summary of what I've learnt (CAVEAT LECTOR: I could still be barking up the wrong tree on some of the details!).

To route a call, there are 3 requisite fields, aside from MYCALL, which in my case is never changed as I'm the sole operator. These are UR (your call), RPT1 (uplink repeater) and RPT2 (downlink repeater).

UR is the field that addresses a particular call sign on the network (at the last heard repeater) if set to a station call. This can be set to CQCQCQ to address any station on the destination repeater(s) or on the simplex frequency (essentially to operate like an analogue radio).

If the RPT1 field is set, then this specifies the uplink repeater call. This is composed of the call sign, plus the special band/port ID always at the 8th character position. Thus, if the callsign is shorter than 7 characters, there will be spaces to pad the string out to this 8th character.

When using a repeater to make calls, the uplink repeater is always your local repeater and the port is always the appropriate band ID for your radio's operating band (conventionally A for 23cm, B for 70cm and C for 2m). All transmissions via the uplink repeater are heard on this port of the repeater by everyone.

To this point, things work similarly to an analogue repeater. However, like IRLP, D-Star allows you to gateway to a downlink repeater, or another port on the same repeaters (i.e. talk on 2m from your 23cm radio). Unlike IRLP, this is done conveniently in terms of call signs and entered directly into the radio, rather than messing around with DTMF tones and node numbers. You can use the following routing settings for different purposes (UR, RPT1, RPT2):

1. To route to a 2m port on a repeater "VE7FOO" from the 23cm port and talk to anyone:

2. To route to a 2m port on a repeater "VE7FOO" from the 23cm port and talk to VE7HAM:

3. To route to the 70cm port on a repeater "VE7BAR" from the VE7FOO 23 cm port, and talk to anyone:

Note that the / format call means "all at desination" (repeater/port), and the "G" port in RPT2 is the repeater's internet gateway port.

4. To route to a VA7HAM on whatever gateway/port he was last heard on the D-Star network:

Aside from these basic principles, I have read the following advice:

- You should always put the gateway into the RPT2 slot if you want DV Dongle users to be able participate. In other words RPT1 is always going to carry your call, and even if you don't need to route across repeaters/ports, putting the a gateway port into RPT2 allows internet connected stations to participate. This suggests that the forms:
... would always be preferable for talking to any station on another repeater or another port on this local repeater.

- You can leave the RPT1 slot empty on some radios, and when you key up the repeater, this field will be filled in automatically. Apparently the repeater is not 'opened' by this interaction. I shall try this on the ID-1. It's probably also a simple way to test that you're getting into the repeater.

Apparently V2 of the Icom repeater control software allows conferences, by using a conference name in the UR field.

All sounds like good fun. I just need to be able to make it into a repeater now to give it a go. Though I had registered with the VE7RAG repeater, it now looks like VA7ICM is going to be my home repeater, so I've requested registration there and hopefully this won't be long in coming (the VE7RAG registration was turned around in a day!).

Thursday, June 11, 2009

ID-1 and D-Star in the shack

The station grew a D-Star capability today as an Icom ID-1 was added as probably the last transceiver for a little while :-)
The shack now has at least a basic capability of operating from 40m through to 23cm, though I'm still waiting for a 2m/70cm/23cm vertical antenna to be delivered as the permanent antenna system for VHF/UHF, complimenting the Cushcraft R8 on HF/6m.

While I'm waiting for the antenna, I have a temporary mag-mount and Comet mobile 1.2GHz vertical with which to set up and test the unit.

As usual, I find it a little bit of a shame that there's no Macintosh software provided for the radio, but this isn't unexpected and Parallels or Fusion serves to run small apps such as the provided control software. I think the ID-1 was developed around the turn of the century and the Mac has only recently been making anything like meaningful market share gains.

Commissioning and using a D-Star system is completely different from a 'normal' analogue radio, as you might expect. So far I have only scanned through the manual and made a very few simple configuration settings: basically setting MY CALL and storing the local D-Star 1.2GHz repeater frequency for DV mode in a memory. I was expecting to see some kind of activity on the repeater frequency, but there was no obvious activity in the 10 minutes or so that I had the radio on and tuned to the correct frequency. Thus, I haven't even been able to test whether the repeater is workable from my little indoor antenna arrangement yet. Hopefully I'll figure that out tomorrow.

How one makes a D-Star digital voice (DV) call through the repeater isn't what I'd call super-clear from the manual. From what I can gather, having set up your MY call, tuned the radio to the repeater frequency, and registered your call sign with the repeater administrator, you are ready to actually make a call. The manual deftly omits to show any actual examples of routing a call through a repeater, and only shows CQCQCQ as the call sign to address as UR (your) call to make a CQ call, but it doesn't show what you put into the repeater box in the address strip. As far as I can tell from a bit of web searching, you need to address the right ports of repeaters through which you wish to connect to the desired call sign (or CQ). Thus, it appears that to send a CQ out through my local repeater's 2m port, I would use both repeater address slots, setting the first to VE7RAG A (my side of the connection is the VE7RAG repeater's "A" port, the conventional name for the 1.2GHz radio on the repeater). The second repeater slot would be set to VE7RAG C (the destination end of the call will be the same repeater's "C" port, the conventional name for the 2m radio on the repeater). Keying the PTT is then supposed to send the call/CQ. It turns out that the port letter has to be in the 8th character position of the repeater call to work properly. None of this D-Star-Fu is noted in the ID-1 manual as far as I can see (unless its in some appendix I haven't read yet). Having read that the gateway software has been upgraded since the initial release, I'm guessing that this isn't mentioned in the radio manuals for reasons of allowing for the details to change - accuracy but not precision!

Hopefully my first D-Star QSO will happen successfully tomorrow - if I can find a willing soul on one of the three local repeater ports! Otherwise, I'll see if I can figure how to point my local repeater at a distant one, perhaps one in an mid-evening time zone somewhere in the world where I might be able to drum up someone settling down to play a little radio after dinner on a Friday evening.

Ham Radio vs The Internet

Since getting back into the hobby a few months ago I've occasionally pontificated about the relationship between 'recreational radio' (mostly what Hams do) and the internet. There are lots of dimensions to this of course, and I'm sure this has been a subject pretty much done to death in the various Ham forums as well as on the air.

Taking a quick look around the club during regular meets, you can't help notice a certain skew in the demographic. The hobby has always been male dominated, and certainly the membership is also skewed according to those who have the time to spare on the hobby. Nevertheless, there are surely far too few young people in the mix to ensure a healthy future (it seems to me anyway). Maybe this isn't as bad as it might seem - perhaps the stats would show that enough people enter the hobby in their 40s and 50s when career and family demands begin to lessen a little. On the other hand, there might be a genuine crisis about to break.

Of course, one of the reasons that young people mightn't be quite so motivated to learn about radio and participate in the hobby is that radio is no longer the only/dominant communications medium if you are initially open to be hooked by the promise of being able to make friends at a distance. I think this was one of the real attractions for me - or perhaps in my case it was more the wonder of being able to do this.

These days, with broadband into essentially every home, with the web, email, instant messaging, chat boards, forums, mailing lists, Twitter, Skype, etc. etc., one is hardly starved of communication channels. Moreover, these cover a whole gamut of 'modes': written, audio, telepresence, video etc., so you are even presented with options to suit your preference - even mood!

The computer has become a window on the world like no other tool in history, and is the ultimate communication and information device, as well as providing for more 'traditional' processing requirements. Indeed, the biggest uptick in computer usage has not been with applications to enhance productivity per se, but rather with applications that amplify social and information bandwidth.

Every one of my kids has grown up with the computer and they have always considered it a way to interact with their existing friends, keep in contact with old friends and even make new ones - irrespective of any issues of locality. They hold essentially uninterrupted dialogues and conferences with their entourage, even when circumstances such as vacations dislocate parties. I'm sure this is a pattern that they will expect to be a constant factor in their lives - in other words they now treat constant high-quality communication to anyone, anywhere at anytime as essentially a 'right'.

A related observation about the 'next' generation (my perspective), at least in the West, is that they have a tendency not to want to wait for anything. They are a consumer generation, wanting the end, and seldom being concerned or interested about the means. They also live in a time of wonders, when new 'superpowers' are regularly bequeathed them through the means of new technology - it all happens so quickly and effortlessly, so I suppose there's little need to want to learn how it works, as it will all happen without this!

Bringing this back to amateur radio, the contrast is quite stark. The hobby is of course rather more than simply providing a way to chat to friends and learn interesting tidbits along the way, but that's still why many people got into it at the beginning, even if they subsequently get hooked on the technical aspects of what makes it actually work.

Still, many people in the hobby today are there because they enjoy the science and technology itself (not just what I'll call "the gadgets", and socialising). I'm sure this will always be the case at some level, because there will always be engineers, scientists, educators and others who will enjoy the 'how'.

As a technical hobby, there is a corollary challenge here. Amateur Radio enthusiasts have historically been at the forefront of advances in radio communications technology, but like every other scientific endeavour, the advances create ever depth, complexity and the need to specialise if you want to stay at the forefront. This makes it increasingly difficult for the larger population to contribute at this level - and perhaps you could argue that this is a dynamic that turns the hobby increasingly away from pursuits around technical advancement and more toward other aspects: social, sport radio, emergency support, etc. If that's true, then the hobby is really less and less about the brass tacks of radio per se, but rather more about learning to operate in various ways. Perhaps the hobby should more openly promote those aspects to the great unwashed, rather than allowing the persistent external perception that the hobby is actually all about obscure electronic circuits.

From a purely technical perspective, the internet (and its modern access points such as mobile phones as well as 'regular' computers) wins hands down over technologies currently deployed in amateur radio. Of course, the internet can sometimes 'go away', leaving other media as superior for a time, but in general it's easy to see (and my kids tell me!) that my iPhone is the pinnacle of communications devices while I'm in range of a functioning network.

On the social side, in comparison with the general internet at least, I do think that Amateur Radio has something special to offer in terms of creating a self-selecting community that by and large has a genuine interest in technical and scientific matters (by they radios, propagation, space, engineering, genetics, whatever). My experience, at least, is that you at least get to start a conversation in areas that are a common interest by definition, and thereafter you often learn interesting new factoids in topics that are much removed from the obvious radio-oriented subjects. I find that this existence of a 'starting point' of common interest, coupled with the fact that most participants are relaxed and in a frame of mind to simply enjoy contact with another human being, is quite a differentiator compared to the internet. For all the hundreds of thousands of communications channels and forums offered by the internet, all too often the kind of conversations had there are characterised by less positive dynamics: grandstanding, competitivity, prima-donna attitudes, and other things besides. The internet is not predominantly used in a spirit of fraternity, and that makes a big difference.

So, it will be interesting to see how Amateur Radio evolves in the future with all the pressures and challenges it will face. Hopefully though, at the very least, the sense of camaraderie can be preserved however the technical backdrop evolves, so it remains a positive experience on balance, and in particular a way to discover new friends and learn new things without so much of the noise, uncertainty and 'temperature' of the internet.

Friday, June 5, 2009

Considering an Icom ID-1

My first impetus to get into radio came at the age of 12, when I was enraptured by the idea of CB and got myself set up with a rig and indoor compact antenna (later to grow into a decent 5/8 wave strapped to the chimney - once my father was persuaded to do the hard work of putting it up there). Looking back, I can see that this was a variant of the attraction that today's youths have toward Instant Messaging, Twitter and other social media. It was a way to enjoy conversing with others from the comfort of your own home (or bedroom), whenever you wanted, and at very low cost.

However, as noted before, my first interest in 'serious' radio leading to my UK amateur radio ticket came when I was introduced to the concept of packet radio. Thus, digital radio has always really been a draw. The computer is a unit of universal processing capability, and as we all know, the amazing opportunities it presents are multiplied by networking. Software is magic - within the medium of the computer and the network, I can weave any spell to make amazing things happen. I'm only limited by my imagination, and my grasp of the 'arcane knowledge' of how to wield all the available power and potential capability.

Now, the wired internet is truly a wonder in our time. Perhaps there were those who dared to imagine what might be possible if all the computers in the world were permanently connected together, but now we essentially live in those times. How quickly it happened, and yet how little we have yet to leverage of the sheer potential it creates. But I digress... Radio too is a perfectly viable medium for carrying signals, yet as I have already blogged it is disappointing that amateur packet radio has lost much of the inertia it once seemed to have. Of course, much of the problem is lack of data rate, and this is a bandwidth issue, which translates to both an issue of use of the available ham bands, and the design of popular radios. So, because 2m and 70cm radios are a cheap and apparently rather acceptable set of compromises for most amateurs, we have not seen much opportunity for those interested in 'speeding up' packet to really be able to hit their stride. This is somewhat less of an issue in the 23cm band, and so its interesting to see that at least Icom and the DSTAR system offers the ID-1 digital rig to provide better data rates on this band.

Looking at DSTAR in more detail, I'm quite tempted to add the ID-1 to my station. It offers something quite unique and interesting. I would definitely be happier if the whole DSTAR stack used in the radio was open source (including the voice grain codec employed, which I understand is included in the radio under license). Nevertheless, with the apparent availability of local DSTAR repeaters, this radio looks like it offers an interesting dimension, distinct from the other HF, VHF and UHF radios in the station.

That's the theory anyway. I think I'd like a chance to play with the DD mode (although my shack is perfectly fed by high-speed cable internet). I'd also like to play with the DSTAR global repeater network (even though I've yet to try IRLP).

A local purveyor of radios say they have sold a total of 3 ID-1s ever, which is interesting. There are other retailers in the city, and plenty of online retailers too, but it perhaps provides an idea of how few of these units are actually being used. Nevertheless, DSTAR is much broader than just local 23cm band simplex (that's the whole point), and so it doesn't matter as much how many radios happen to have been sold in your locality alone. Anyway, it would be interesting to hear directly from people who have bought this radio - what their expectations were and how/if they were fulfilled in practice.

Thursday, June 4, 2009

Testing VisualQTH

I took the VisualQTH app to the club (NSARC) today and tested it with the club computers running the N1MM software, with the help of Dave Shipman VA7AM.

The app now has some extra 'stats features' along the bottom of the window, and looks like this:

Once we had added the requisite lines to the N1MM .ini file to have it send out UDP packets to the VisualQTH machine, the software was tested with the master logging machine in the radio room, and it worked fine. The other two stations also needed to have these configuration lines added - I had wondered whether the master machine would transmit UDP for all logging records send from the slave machines, but this is clearly not how it works.

Once running, we did a few tests, including attempting to send near-simultaneous contacts from two machines, and all seems well. There are some cases where there are no QRZ records available at all for callsigns (in which case the station lat/lon will be 0,0), which VisualQTH should probably not plot, even if it adds a database entry and a 'slot' in the QSL cards column. I'll make a change to the software to avoid plotting stations with no lat/lon, and to use a particular image in the QSL cards column if no details are available online.

There was also talk of validating station callsign formats, but this entails finding some list of all legal formats for all countries around the world, and I'm not sure if such a thing exists. One could probably research this and build a list of validation patterns without much technical difficulty, but that would probably take more time than I have available.

Otherwise, the next steps are to present this to the plenary session of the club at next week's "field day planning" meeting, and see if there are any suggestions that I can relatively easily achieve in the remaining time before the field day on w/e of June 27/28.

Monday, June 1, 2009

Adding some polish

Now that the main features of VisualQTH seem to be working, I have time to tweak a little bit.

The app currently looks like this:

This shot is taken after manually entering a few stations that are dotted around the world enough to have the map automatically zoom out to essentially its fullest extent. A station in Australia, North America and the UK was sufficient to do this.

Previously, if no station image (QSL card) had been obtainable via QRZ, then the contact would have appeared mostly blank in the contact stack to the right of the map. This isn't much fun, yet many stations have not registered a station image of any sort with the QRZ database. So, in this case I have opted to display the station country's flag - if this can be obtained via geocoding on other available fields. There will still be cases where no country code can be determined from QRZ information, and in this case the log record could be used, or I could encode the callsign prefixes for all countries (an obvious step really), but getting this data together and formatting it may take a little while. In the meantime, the lookup from other QRZ fields seems to be working very well (it's possible the country field is always filled when a callsign query is made against the QRZ database too - I haven't bothered to verify this though).

Image aspect ratio is now preserved for downloaded images. Before this, images were stretched to fit the standard QSL card aspect, which doesn't work with a surprising number of images I've found in the QRZ database!

In this screen shot, you can also see the beginnings of the stats information in the lower portion of the display. So far there's only a simple pie chart for contact counties, but given time there should be other stats. I'm thinking of adding "most distant stations" and "contacts per hour", being metrics that are possibly of interest to observers during field day operating.