All posts by Andy VE7CXZ

FT8, VHF and a side of W*TF

*Why

I’ve parked in worse places

For a hobby that’s been around for years, there’s always something new with amateur radio – and right now that thing is FT8. Released as a new mode as part of WSJT-X in 2017, it’s quickly become the dominant digital mode due to its ease of use, suitability for low signal environments and fast exchanges. Such is its popularity, the vast majority of spots currently submitted to PSK Reporter are FT8 (and you can see the current statistics here). For those familiar with other modes, the best way to describe it is as JT65 but transmitted by excited raccoons on crack, with each cycle taking just 15 seconds instead of JT65’s 60. This allows for a complete exchange from an initial CQ to the final 73 to take just 90 seconds. It’s definitely not a ragchewing mode though – again like JT65, each transmission is only capable of carrying a handful of characters – 13 in free text mode, and slightly more when using one of the predefined formats. Like most things related to amateur radio, it has its detractors (even I’ve moaned on Twitter about the effect it’s had on other digital modes), but that still doesn’t take away from the fun of having a new mode that makes it possible to make a whole bunch of contacts in sometimes less than favourable conditions.

*cue Enter Sandman*

Anyway, as fun as it is, there’s nothing more fun than pushing the envelope a bit. I’m not going to win any prizes for anything novel, but going a little bit outside of the norm is always good for a laugh. So, this past Saturday I decided to give 6m a try. Checking PSK Reporter showed a few stations monitoring 6m in and around the Pacific Northwest, so I dusted off the multiband vertical, stuck it on the roof of the truck and tuned it for 6m while sitting at my usual spot on Mt Tolmie. After a few tests to make sure nothing caught fire (did you know you can melt the glue around the relays inside a Z100 tuner? Neither did I), I set WSJT-X CQing.

And nothing happened.

And still nothing happened.

May not be an accurate representation of the circumstances

The weather was nice though…

Photo angled to hide garbage

And then finally, after about 20 minutes of not much happening, I got a response from VE7DAY, who after a quick QRZ search is in Campbell River – about 250km to the northwest. Signal reports were exchanged, and then a minute or so later I got another response, this time from VE7DXW in North Vancouver. I didn’t manage to get any more bites after these two, but it proves that even with a small setup, you can still have fun with VHF.

Not being one to settle though, later on Saturday – after a few well-received cans of cider – Jordan VA7TLZ and I wondered if we could manage an FT8 contact, but this time on 2m.

Dramatic reenactment, 4 cans of cider in

We’re about 4.5km apart, which would normally be easy, but we’re both in apartment buildings full of metal, and facing the wrong side of our respective buildings – Jordan facing south, and me facing west…

This was a stupid idea

But just because not every idea you have after a few drinks is a good idea, it doesn’t mean that all of them are terrible, because eventually…

What’s that coming over the hill?

…Jordan’s responses to my repeated CQs came through, and both of us now have an FT8 contact on 2m in our respective logs.

¯\_(ツ)_/¯

I guess the moral of this story is that just because it sounds like a stupid idea, it doesn’t mean that… okay fine, it was a stupid idea.

Recorded for posterity

Look forward to my next post, where we try moonbounce with stock antennas on a pair of Baofengs!*

 

* probably not, unless someone lets me at the liquor store again

First JT65 contact of 2017

Okay, so it’s probably the first JT65 contact I’ve had in more than a few years, but it’s definitely the first of this year.

I headed out this evening – a little later on than planned – to Mt Tolmie, put the 20m vertical on the roof of the truck and tuned the TS480 to 14.070, hoping to make some PSK contacts. Disappointingly, however, there was nothing to be heard. After listening around some of the other bands, I went back to 20m and listened up on 14.076, and heard the unmistakable sound of JT65.

As luck would have it, just last week I’d reinstalled wsjtx on the netbook that I use for radio, so given the lack of anything else to do fired it up and let it decode for a while. After some minor tweaking – namely correcting the time on the netbook, as JT65 is sensitive to incorrect clock settings – I saw a bunch of CQs decoded, including some from Australia and New Zealand.

Figuring that I may as well give it a try, I replied to one of them – VK4NJR in Queensland. Straight away they replied, giving me a signal report. I sent mine back, received the customary “73“, and into the log it went. It’s not every day you make a 12,000km QSO quite so easily.

Using WSJT-X to communicate with VK4NJR

If you’re not familiar with JT65, it’s a mode designed for low power and/or high noise situations. It’s a digital mode, using FSK (frequency-shift keying) to convey information. Because it can decode messages that are inaudible to the human ear, it relies on accurate clocks (at least to a few seconds) to make sure that each transmission starts at the beginning of a minute. Each transmission lasts for nearly the full minute, and in that time transmits a maximum of only 13 characters, which should give you an idea of how robust this mode is designed to be.

JT65 is part of a larger suite of modes developed by Joe Taylor K1JT, designed for weak-signal communication and for some of the more exotic methods of communication such as meteor scatter. For me, making a contact over such a long distance and with low power (in today’s case, around 5-10W) makes the whole thing a lot more fun.

Finally, there’s a really useful website if you’re working with JT65 called PSK Automatic Propagation Reporter. As the name suggests, it’s primarily aimed at collecting automated reports from people using PSK, but it’s also used for other modes – JT65 being one of them. It’s useful to be able to see where you’re being heard (or not, as the case may be) and I usually have it open somewhere while I’m on the radio.

pskreporter.info showing that I was heard in Australia, New Zealand and Brazil, amongst others!

The (less temporary) return of VE7CXZ

My last post here was almost 3 years ago, somewhat ironically referring to me (for arcane, wonderfully regulatory reasons) using my UK callsign while on a short trip to Washington. After that, to the outside observer it would seem that the bit rot really set in. The reality, though, is… well, pretty much the same.

Being in an apartment rather than a house means that operating HF in particular is a challenge, and so my options are pretty limited. It’s for this reason that virtually all of my HF operation nowadays is portable, which in turn means there’s a lot more effort involved than just plonking my backside down at my desk at home. Anyway, the gist of this is that I gradually spent my time doing other things – mostly playing Ingress – and other than spitting out APRS beacons from the D710 in my truck, radio mostly went on the most back of back-burners.

However, a few months ago that started to change again. After encouraging a friend to get licensed I started to remember the fun stuff I’ve done with amateur radio in the past and decided that it was time to ditch my half-arsed portable set up and put things together properly. I bit the bullet and ordered a few things I’ve been thinking about for a while (which are subjects for future posts) and I’m well on the way to having an actual, (semi-)reliable set up. So much so that with the RSGB IOTA contest coming up at the end of July, I decided to apply to ISED Canada for a special event callsign and after parting with $60 was given VC7A to use for the weekend. Since I now have 36 cans of cider’s worth of a callsign, you could say I have a vested interest in using it so the next month will be me preparing for my first radio contest in 5 years. I just hope I’ve remembered how to do it…

Playing with packet radio in the CRD

The Capital Regional District (commonly referred to as the CRD) is the name for the region that contains and surrounds Victoria, the capital of BC. The CRD is made up of a number of municipalities, and through Emergency Management BC, each municipality has its own Emergency Operations Centre, or EOC. Part of each EOC usually includes some kind of communications facility, which is run by licensed amateur radio volunteers, and the facility normally has a packet station that can be used to pass messages back and forth.

What this means is that if packet radio is something you’re interested in, Victoria has plenty to keep you occupied.

Connecting to a node

First, pick a node from the CRERCC Packet Station page. For this example, I went with VE7SEP-7, which is located at the Saanich EOC.ve7sep7

For anyone familiar with packet nodes, the above should look pretty familiar. If you’re not, then the basic functionality is that you can connect through to another node, list the other nodes that this node has heard, and disconnect.

I hit J (or Heard) to see the other nodes than VE7SEP-7 had heard, and you can see that my call is the latest in the list:-

ve7sep7-2

Connecting to other nodes

While you’re connected to a node, you can usually use the C (or Connect) command to connect to another node that’s on the same frequency. This is useful if you can’t hit the other node directly, but the node you’re connected to can hit you and the other node.

For example, from Langford I can’t connect to VE7PEP-7 directly, but I can – as we saw above – connect to VE7SEP. When we looked at the nodes that VE7SEP-7 has heard recently, we can see that VE7PEP-7 is in there, which means there’s a good chance VE7SEP-7 can connect to it. To try it, we can type C VE7PEP-7, and cross our fingers:-

ve7sep7-3

Success! We’re now connected to VE7PEP-7 and can use it as if we were connected directly. This also means in theory that we could jump to yet another node, although this is not always a good idea, which I’ll touch on later.

Using digipeaters

The above method for reaching packet nodes that we can’t hit directly works, but is a bit cumbersome. What if we could connect to our intended node via the closer node, but without having to manually connect to the closer node first? We can, and it’s known as digipeating.

In this example, I can’t connect to the packet station VE7RAH-7:-

term-ve7rah-1

(I’m using Linux for these examples – AX25 is well maintained, relatively easy to set up and simple to use, and I’ll cover it in a future post)

As you can see, I tried to connect using the axcall command, but I didn’t get a response and eventually aborted the connection attempt. As before, I know I can reach VE7SEP-7 directly, so let’s adjust our command:-

term-ve7rah-2

 

ve7rah-digi

…and we’re connected!

There is a subtle difference at work here, and that’s that in our first example, we were creating separate connections first to a nearby node, then from the nearby node to a distant node, while in our second example we’re creating a single connection to a distant node, but relaying it through a nearby node . The configuration needed to support these two different methods is different, so while one may work, the other may not. From the examples above, we can see that VE7SEP-7 supports both.

A further example to highlight this is that although I can connect to WF7W-7 (and, although not shown, I know WF7W-7 can see VE7RAH-7):-

wf7w-7

…trying to use it as a digipeater fails:-

wf7w-digi

 

A word about too many hops

As fun as bouncing around different nodes can be, it’s best to keep it to a minimum. For starters, for each hop you add to the connection, the more delay there will be when issuing commands to the intended node. This is because each node in the path has to retransmit your packet and wait for a response before it can reply back to you. Add other stations into the mix or any sort of interference and having any more than 1 or 2 hops can be unusable.

The second – and perhaps bigger – problem is that all these additional packets being generated will tie up the channel, making it more difficult for other users on the same channel.

What next?

What I’ve shown above is just scratching the surface, and in future posts I’ll cover setting up AX25 on Linux, and how a tool call RMS Express is used to provide worldwide e-mail services over packet radio networks!

Radio Weekends: HF digital modes

This Saturday, Josh VA7ACQ, Dom VA7CRO and myself stationed ourselves at various places around the CRD with the intention of running a few tests with various digital modes on HF. Dom went up to Sidney and Josh set up at Beaver Lake, while I headed for the usual spot down at Esquimalt Lagoon.

VA7CRO, VA7ACQ and VE7CXZ spread out across the CRD
VA7CRO, VA7ACQ and VE7CXZ spread out across the CRD

We settled on using 20m, hoping for a balance of less QRM and greater efficiency with the compact vertical antennas that Dom and I were using, while being not as useful for ground-wave as 40m may have been. After a bit of tweaking of audio levels and picking a dial frequency of 14.088MHz, Dom and I made contact with PSK31.

Working VA7CRO with BPSK31
Working VA7CRO with PSK31

Once we’d played with PSK31 for a while, we then moved to a much older mode by the name of Hellschreiber. Developed in the late 1920s, Hellschreiber (or Feldhellschreiber) sends text as a series of pixels, scanned left to right.

VE7CXZ, VA7CRO and VA7ACQ (in that order) working with Feld-Hell
VE7CXZ, VA7CRO and VA7ACQ (in that order) working with Feld-Hell

After this, we tried a whole bunch of other modes, including RTTY, MT63, Olivia, and MFSK – where Josh and I even managed to exchange small images! It was also a useful test of the RSID functionality in both FLdigi (which I was using) and DM780 (which both Josh and Dom were using), which sends a brief burst of MFSK before the actual transmission to both identify the mode being used and to centre the decoder on the right frequency.

I forgot to take any more screenshots, so here's another Feld-Hell one. You start to get a bit silly when you're sat in a cold truck at the seafront...
I forgot to take any more screenshots, so here’s another Feld-Hell one. You start to get a bit silly when you’re sat in a cold truck at the seafront…

Some findings from the afternoon’s experiments were that MT63 can be very particular about being on the correct frequency, that DM780 uses fixed centre frequencies for MT63 whereas FLdigi doesn’t, and – very much related to the first two – that the USB sound card I use for digital modes produces audio that is off by a not insignificant amount – about 40Hz.

By now it was starting to get a bit on the cold side, so we all made our way to Six Mile to warm up and for a much-needed beer.

The (temporary) return of M0VKG

It’s been almost two years since I got my Canadian amateur radio licence, but before then I was licensed in the UK as M0VKG. When I first moved to Canada in July 2012 I operated for a while as M0VKG/VE7, but since then – other than a visit back to the motherland in February of this year – my UK callsign has been mostly dormant.

Mostly.

International agreements can be complicated affairs, and amateur radio doesn’t escape this fact. The CEPT agreement is probably the biggest, and generally allows an amateur radio operator from one country to operate temporarily in another country, and in some cases actually acquire a licence in the other country based on their existing one.

Another agreement, which is much closer to home, is that between Canada and the US, which allows most amateur radio operators of both countries to operate in both countries. I say most, because the agreement states that it applies to citizens of both countries. This means that technically, if you aren’t either a Canadian or a US citizen, you’re not covered by the agreement. As a British citizen, this means it doesn’t cover me!

I recently had my application for permanent residency in Canada approved, which meant – for boring immigration reasons I won’t go into – that I had to leave the country and reenter again. From here, that means the easiest way is to drive to the US border, which is what I did. However, as explained above, I can’t legally operate as VE7CXZ in the US, so I had to fall back on M0VKG. Luckily, the Kenwood TM-D710 has a features which lets you store different ‘profiles’ in the radio, while sharing the same channel memories. This means that I was able to set up a profile on the TM-D710 that instead of using my usual callsign and SSID of VE7CXZ-1, I could quickly switch to using M0VKG-9 at – literally – the touch of a button.

Which, to wrap it all up, explains the reason for this map:-

APRS track from Victoria, BC to Ferndale, WA and back
APRS track from Victoria, BC to Ferndale, WA and back

Above the clouds with APRS

While out at my new favourite spot for HF radio the other weekend, I happened to notice an odd callsign pop up on APRS:- IMG_20140803_185248

Holding a UK callsign, it doesn’t take much to recognise  another one when you see it. This wasn’t any normal APRS station, though – it was a high altitude balloon on its way around the world!

Leo Bodnar M0XER has been making and releasing high-altitude balloons for some time, and a few have made it all the way around the world. At the time, this one (using the SSID M0XER-6) was just over 100km south of me, over the Olympic National Park in Washington state. It eventually came within 95km of me, before heading eastwards and eventually crossing the border into Canada.

Leo’s balloons are a great example of what APRS can be used for, and more information (including a map of the flight path) about this particular balloon (also known as B-66) can be found here.

VE7CXZ/P from the Coburg Peninsula

image
The Focus of Doom, ready for portable HF

I’ve recently started operating portable from the Coburg Peninsula, which is a narrow strip of land by the historic Fort Rodd Hill and Fisgard Lighthouse. Situated in the south of Colwood, BC, it looks out onto the Strait of Juan De Fuca and therefore has great takeoff on HF, especially to the south towards Washington and the rest of the continental US.

image
Working AF7ES with PSK31

So far I’ve managed to work all over the US and in Europe, including W1AW/P and stations in Hungary and Slovenia. I’m using a Kenwood TS480SAT for SSB and a Yaesu FT897D for digimodes, with an Acer netbook running FLdigi for the digimodes and logging.

I’m hoping to get my second callsign of VA7HTJ on the air over the coming weeks, and some testing for the upcoming CQWW SSB contest.