AmateurRadio.com

I have never had a JT65A contact on 30m. This is surprising. The 30m band is the most popular band for the WSPR mode which has demonstrated that it provides good propagation 24 hours a day. The trouble is that there is nowhere for JT65A to operate. The JT65-HF software frequency menu offers two choices for VFO frequencies: 10.139MHz and 10.147MHz. But the former will cause interference to WSPR and have you fighting it out with a phalanx of PSK signals and the latter conflicts with the frequencies used by APRS packet and other digital networks.

To those who wonder why you can’t just find a clear frequency and operate I would point out that this doesn’t work with weak signal digital modes. Not only will users of other modes not know you’re there and call on top of you, but the DX you hope to work won’t be able to find you either. So it’s important to have a frequency of operation that has a good chance of being clear, where other users know to listen.

From recent discussions it appears that the two previously mentioned 30m frequencies were chosen in a desire to find a place to operate that fits in with the IARU Region 1 and Region 3 bandplans. In the USA (which is Region 2) narrow band digital modes can use 10.130-10.140MHz but in the rest of the world the area up to 10.140MHz is allocated to CW.

I have long believed (and have probably written before in this blog) that it is absurd to have different bandplans and different rules for different parts of the world because radio waves don’t stop at national boundaries. I suspect that the allocation of just 10kHz for digital modes was made back in 1979 when the 30m was first allocated to amateurs, when the only digital mode was RTTY. Since then, and especially in the last ten years or so, there has been an explosion in the number of digital mode users (due to the increasing use of computers) as well as a proliferation of different digital modes. It is time the band plans were updated to reflect that.

I think the bandplan for 30m in the rest of the world should be brought into line with that in the USA. I have nothing against the CW mode but if 30kHz is enough for US amateurs to get by with then the rest of the world can also manage with 30kHz.

JT65A is a wonderful mode, and JT65-HF by Joe Large W6CQZ is a wonderful program that makes it enormous fun to operate. True, the mode only allows the exchange of signal reports, though a very brief amount of extra information (such as power and antenna) can be sent in a custom message. But so many contacts using other modes also only result in the exchange of such limited information. On the other hand, there is a certain magic in seeing faint musical tones sent by a faraway station translated into a message on your screen. Many people have said that JT65A is addictive. I agree.

If there is one problem with the mode, it is that the 50 second transmit cycles where nothing is decoded on to the screen until the end makes it easy for your attention to wander. I’m ashamed to admit it, but many is the time someone has replied to my calls and I missed it because my mind was elsewhere. So I was really pleased to discover an add-on for JT65-HF written by Laurie VK3AMA called JT-Alert. One of a pair of add-ons he has written (the other is a kind of macro tool for custom messages) it watches the decoded text and sounds an audible alert when a CQ call is received or when a station replies to your call. You can have different sounds for the two alerts, and the audible alert is optional and can be disabled. The tool can dock to the bottom of the JT65-HF window (as in the screenshot above) so the two function as one program.

I have been monitoring for activity on ten metres, which is dead most of the time. It would get pretty boring sitting in front of a blank window for hours at a time but I have set the CQ alert to a loud klaxon which will bring me running to the shack from wherever I am in the house if/when a call on 10m is received. It’s a really useful tool (though it does get a bit annoying when working on 20m and my XYL isn’t so keen on it either!)

I made a number of nice contacts on 20m using JT65A today, including CO2VE (Cuba), PJ2MI (Curacao) and LU6AM (Argentina). I also worked a fellow blogger, David K2DBK. Unfortunately my custom message to David didn’t get sent as I got caught by a quirk in the JT65-HF program that was pointed out to me later by members of the JT65-HF support group. Apparently if you start a message with 73, those two characters are sent as a special shorthand sequence and the rest of the custom message is ignored. I had actually read that in the documentation, but I’m afraid due to the onset of senility RTFM often isn’t the answer as I FTFM (Forget The Frigging Manual) immediately after I’ve read it. Oh well.  🙁

I finally got caught up with things so I could find time to experience the HF band conditions everyone has been talking about. I put the K3 on 10m WSPR while I was doing my computer jobs. I missed some chances of being heard because the WSPR rig control doesn’t switch the K3 into DATA mode and in SSB mode only the microphone is live not the line input. My apologies if the sound of typing affected anyone’s WSPR reception! After spotting the error and correcting it I was received by five VK stations, which is quite pleasing for 20 watts to an attic dipole!

When I was finished with the computer I had a listen around the 10m band. There wasn’t as much happening as the WSPR results would suggest so I tried 12m, where some PSK31 was heard. After making one contact there (ER1RY, Moldova) I went back to 10m and saw some faint traces. I worked several Russians and heard but didn’t work three South African stations. I was also spotted from Madagascar by someone on the PSK Reporter site. That would have been a nice contact! I checked the SSB end from time to time but only heard a handful of signals too weak to work.

Ten metres is one of my favourite bands so it is great to see some signs of life. But I fear that improved propagation is going to bring problems for digital mode enthusiasts. As Paul, PC4T complains in his latest blog post, when you get good propagation people operate wherever they can within the band plan so the weak signal modes get trampled over by the wide, loud modes.

Unfortunately there is no “gentleman’s agreement” that says PSK has exclusive use of 14.070 – 14.072 or that only JT65A can be used from 14.076 to 14.078. Here in Europe, even the band plan separating CW, digital and voice modes is only a gentleman’s agreement. The frequencies mentioned above, like the QRP frequencies and others, are just “watering holes” that benefit people who operate those modes but can be ignored by others with no fear of any official penalty.

There has been an explosion in the use of digital modes over the last few years as more hams connect their computers to their radios and discover sound card software. The effect of this has mainly been that you could often find PSK31 activity when nothing else could be heard. Poor conditions have prevented the bands from getting too overcrowded.

But with better propagation people are going to be fighting for space. PSK is going to need to spread beyond its usual 2kHz on the most popular bands, as will JT65A. The “modes du jour” most of which offer no significant benefit over those that already exist will cause confusion by operating on top of one another. And the outmoded, inefficient RTTY, for which no technical justification for its continued use exists, will stomp over everything running the legal limit just as it always has, only this time more people are going to have their contacts spoiled and get angry about it.

It’s going to be a fun few years!

I popped up to the shack after watching some evening TV and decided to have a listen to what was happening on JT65A on 40m. I tuned my K3 to 7.076MHz and had only been listening for a couple of minutes when I saw a CQ call from VK6BN appear on the screen. I only just managed to set up a reply before the start of the transmit period and you could have knocked me down with a feather when he came back with a report! We completed the QSO in the minimum 6 minutes.

I’ve been reported in VK before using WSPR, that’s nothing unusual, but this is my first ever two-way contact with Australia on any band or mode and I’m pretty amazed to have achieved it on 40m of all bands using just 30 watts to my attic dipole. JT65A really is amazing!

As if that wasn’t enough, I then worked KE1AF for my first contact with North America on 40m. So I shall be going to bed this evening feeling pretty pleased!

My bureau-workshop

I have sometimes seen comments to this blog that are disparaging towards the idea of stealth operation. I don’t for a moment accept that stealth antennas are worse than the modest wire antennas many hams in the UK who don’t have deep pockets, large gardens and amazingly tolerant neighbours use. RF doesn’t care whether an antenna is visible or not, it’s what you do to make the antenna invisible that might compromise performance and with the small gardens without trees that so many of us in the UK have, most of us have to live with compromise.

But the real test of a ham radio station is whether it allows you to pursue enough activities to maintain interest in the hobby. And based on that criterion I think G4ILO does very well. One of the best additions to the shack was to make a dedicated work area for construction in a bureau unit whose door drops down to make a work surface and which can be closed when I have done enough without having to put everything away. I have a greater interest in building stuff now that I have somewhere to do it.

In fact there are more things I would like to do, radio-wise, than I have time to do. Last weekend, for example, I would like to have tried making some contacts in the worldwide RTTY contest but of all the radio things I did that weekend, giving away some contest points was something I didn’t get around to.

Today I was trying to finish up my homebrew SignaLink USB clone, but I made the mistake of turning the K3 on and leaving JT65-HF running and I kept on being distracted by seeing CQ calls from DX stations. In between work on the interface I made contacts with YV6BFE, N8ABY, AA1CZ and KD0AGX plus a couple of Europeans, all using 25W to the attic dipole. My signals were spotted in Japan and far eastern Russia, though I didn’t hear anyone that far east. DU1GM, whom I worked a few days ago, was calling for most of the afternoon with no takers.

The SignaLink USB clone is just about finished and does work. After I made up an interface cable between it and the FT-817ND I made one solid PSK31 contact with F5TTI on 30m with it on the test bench. So now it just has to be put into its case and it will be completed.

Several of my blogging compadres have written recently about using the JT65-HF software by W6CQZ so I thought I would give it another try to see if I could understand what all the fuss is about. This is not the first time I have tried the program. I tried it at the beginning of the year. In fact, it was the main reason for upgrading my shack computer because the old one could not decode the received signals quickly enough to give me time to reply to calls. But having got the new PC I found the mode rather uninvolving as contacts are made just by clicking buttons to send computer-determined reports and you can’t even tell which of the signals you can hear is the one you are replying to.

I decided to run the K3 at 5W into the dipole because the K2 was doing 30m APRS gateway duty on the magnetic loop and the two antennas are only a few feet apart. But there was no interference. I’m not sure how much power people normally use on this mode but I might try more next time. My new shack computer coped easily, decoding the received JT65A signals in a second or so despite the fact that it was simultaneously running two APRS gateways one of which was using TrueTTY and a USB sound card to decode the packet data.

I found a free spot on the waterfall, sent a CQ and two people immediately came back to me at the same time. I didn’t decode anything! I called again and this time three people replied! I sent CQ once more and this time the first two must have decided I was either deaf or an idiot which left just one signal on my frequency: OE1LIC, for my first contact of the day. My second CQ raised RZ6AUJ, Alex for another contact and that was all I had time for before dinner.

One of the features of JT65-HF is that it automatically links in to the PSK Reporter network so you can see all the stations you heard on a map and, even more interestingly, all those that heard you. I remembered this and popped up to the shack after dinner to grab a screen shot. As you can see, my 5W to an attic dipole was heard by two stations on the west coast of the USA, and I was only on the air for about 20 minutes! The small blob on the west coast is VE7IRA who was heard by me despite the appalling S9 interference I get on this band, which was reduced to about an S3 by the MFJ-1026 noise canceller using a PA0RDT mini-whip for a noise antenna.

I still find using JT65A on HF feels a bit odd but I can understand why it has become so popular, even addictive. It takes up little band space and doesn’t interfere with other band users unlike a certain R** digital mode. I said this before and didn’t end up doing it but I think I will spend a bit more time using JT65-HF to see what I can work and whether I can join the crowd of enthusiasts for this unusual digital mode.

As someone who has quite often used WSPR, I have often said that it would be nice to be able to exchange reports with other stations and confirm the “contact”. I felt this simply because the WSPR network is a friendly community and it feels right somehow to be able to do that, just as you would confirm an enjoyable contact on another mode.

Modes like the little used WSPR QSO mode and JT65A on HF offer the chance to make two way QSOs using similar power levels to WSPR. But my recent experience using JT65A on HF, and more recently watching a station in Iceland take half an hour to try to exchange a signal report and confirmation with a station in Brazil using a certain other weak signal mode led me to wonder if in trying to make it possible to make “contacts” using the least possible power we have thrown the baby out with the bath water.

Communicating via moonbounce (EME) on VHF has always been about exchanging the barest minimum of information, because even doing that is a major achievement. But on HF it is always possible to have a proper contact, even if it means using a bit more power or waiting until propagation is a bit better. So why are we endeavouring to use modes designed for EME on the HF bands? What is actually being achieved? Someone’s computer is able to pick a few characters of information out of my barely audible signal, with the help of heavy error correction and the fact that the message format is known. My computer is able to do the same with his. Is this actually a contact?

Yesterday I tried for the first time in several years to use the Olivia digital mode. Before I did, I Googled up some information about it, and came across a Yahoo group containing a post by Waldis, VK1WJ. He wrote: “Yesterday I had a sked with DJ2UK on 20m in JT65A. Bert came in with around -17dB but he couldn’t decode my signal. After a while I saw in SPECJT that he had switched to Olivia 8/125. So I did the same, and we had quite a long error-free QSO. Olivia 8/125 is not exactly fast, but it still beats JT65A hands down. May be we could entice our JT65A friends to try Olivia instead?”

According to Waldis, instead of exchanging a couple of numbers using JT65A, you could have an actual (if slow) conversation using the 8/125 variant of Olivia. But the JT modes are currently in vogue, whereas Olivia – being developed in 2003 – is yesterday’s news. People are raving about the capabilities of a certain other mode that is making a lot of news recently. Have all these people actually tried some of the forgotten modes? Because I think if they did they might wonder what all the fuss was about and whether the newcomer really justifies its use of bandwidth.

What was I saying about reinventing the wheel?