Wednesday, 30 March 2016

Radios for two decades and more on the IC-7300

Radios for two decades? Does that mean a radio lasting two decades, or two radios "of the decade"?

Both.

Bri, G0MJI asked me which radio I bought when I was 40 which I still have now that I am 60? My enigmatic reply was that it had a cassette recorder attached. Well here it is ...
Note to photographer: you really must try to correct for those converging verticals. Why don't you try pointing the camera at the radio?

A Roberts RC818 - quite something in 1995. I bought it in John Lewis in Edinburgh and it is still in the original box, complete with the book and the wire antenna. I wonder will the IC-7300 still be around in 2035?

This radio (and of course its Sangean version too) was a pretty good performer for its day. Big, certainly, but I wanted general coverage and a BFO to receive SSB and CW. I think you have to put this into context. I am a child of an era when rigs drifted like mad. Old Codars and Trio 9R5DS and Yaesu FR50Bs were all over the place. The whole thing changed with the arrival of the Yaesu FRG7. This was my idea of a radio of the post FRG7 vintage which I could cart about with me. It went to Greece straight away, and pretty well every year after that it was lugged off to wherever I was going. Later a rather smaller Roberts arrived, and in due course the FT-817 kicked them both out.

The Roberts had its limitations. The VFO synthesiser steps were either too wide or too narrow and from what I recall the small steps were too small to register on the digital readout. So you had to count them. But it worked and it was even stable enough to receive WSPR.

Moving on to this decade's radio, the IC-7300 is certainly a remarkable beast.

Last evening's 4m contest was AWFUL. The conditions were woeful. I worked two for sure and probably a third. I heard almost nothing else. Not a good place to test out a rig. Halfway through I changed over to the IC-7100 for comparison but I could hear nothing on it either.

I did get comments on the good tx audio quality (is that in comparison with the IC-7100?). But the major point to note was the different receiving experience. I listened to a distant station having a ragchew. Turning off the preamp left me able to hear the speech clearly even though it was very weak. The lack of noise was remarkable.

Some time ago I agonised over the difference between the sensitivity, noise and AGC performance of my Flex 1500 (since sold) and my FT-817. All that is here. It seems that I have to learn that lesson again. SDRs are just different. They sound different to listen to. There is a quality to the sound which is missing in superhet radios, or at least the ones I can afford to buy.

Right, also on the IC-7300 front, I have added the Icom RB1 remote operating software (thanks again Scott). This means I can control the 7300 from my shack computer. Any networked computer actually. I should also be able to show the waterfall on the computer screen, but so far that aspect hasn't worked. The software said I have to raise the USB data rate to watch the waterfall, which is fair enough. However, when I do that the CAT control gets lost. I have changed the COM port speed and the software communication speed, but I have not managed to get the rig to follow suit. Yet.

Given that there was not much to work I tried putting the IC-7300 onto HF duty. I set up WSPR but as the software does not yet support the 7300, I used a second version of "CAT-7200" to work the PTT. I had forgotten that this version of the WSJT-X suite had "frequency hopping" turned on but it was not controlling the rig frequency, so several of my 40m spots were reported as having been heard on 12m and 10m. Oh dear, silly mistake to make. Anyway, all the data software connected to the rig easily. And it transmitted WSPR data which other stations decoded.

Plugging the 7300 into the PC (you have to provide your own USB lead) went smoothly. I already had the drivers loaded from the IC-7100. The COM port and virtual audio card installed straight away (unlike the 7100 there is only one COM port as there is no GPS input). Setting up the memories and function menu should be easy for anyone familiar with Icom's funny little ways.

I have been comparing the 7300 and 7100 on weak signals. As before, I set up a co-ax divider and fed the two rigs into two versions of WSJT. Then I turned the beam to alter the strength of various beacons. Also, the Buxton beacon had some helpful QSB. I doubt if there is much to learn from the images but here is one of them
Click if you want to enlarge. The 7100 is on the left, the 7300 on the right. Rather than the actual signal strength it is again the noise which surprises me. I set both gain controls to 0dB for some low signal comparisons, but look at the noise on the 7100 traces. Also, on the main WSJT screen (below the signal trace), top right of that bottom screen, the width of the two signals is different on the 7300 and the 7100. The 7300 has a very narrow pulse, the 7100 has a much wider base. This seems to support my impression that it was easier to listen to a weak signal on the 7300.

I'll not go into the rest of the tests here now. Don't worry, there will be more. But after hours of sensitivity tests there seems to be nothing to tell at the margin between the 7100 and the 7300 - on 70MHz at least. That was watching them on the screen, but listening is definitely different.

It is still too soon to say much more. Everything on the 7300 which I have tried so far works. I just need some decent HF propagation to test anything else.

I'll also try for some meteor scatter tonight. Maybe the conditions which are messing up HF will produce some aurora. I guess Thursday or Friday might produce something like that (or maybe not).

POSTSCRIPT. I have been writing this with the two rigs connected and the beam pointing at the Carrickfergus beacon on 70.027 (GB3CFG IO74cr 263km). Actually they were both a bit off the right frequency as I could not find the beacon in the noise. Then I noticed that I could see the carrier of the beacon on the 7300 waterfall. Thus I could tune it in exactly (70.02658) and then I could just ... just ... hear it. Tuning the 7100 to the same point produced nothing. Now that is the way SDR is supposed to work. Watch the band as you work a specific frequency.

Ahh, I feel happier after that.

73

Jim
GM4FVM

Tuesday, 29 March 2016

New arrival: Icom IC-7300.

Well, it did not come as a shock, as I had ordered it in October for my birthday, which was in December. I have had my bus pass for over 3 months now.

Last week they asked me to pay for the rig.

Then today I got this message from parcel company DPD:-

Your order will be delivered today by David, your DPD driver, between 12:44 and 13:44
Follow my parcel now - Live tracking of your parcel below:

David is currently making delivery number 1, you are delivery number 29.

David is approximately 3 hours 30 minutes away from you.

David was true to his word and it duly arrived at 12:44.


As usual, click the photos to enlarge if you need to.

Not that I have had time to do much.

As it is planned to use it mostly on 70MHz that is where I pointed it right away. Like the IC-7100 it does not have a band tab for 70MHz, but you select 50MHz and tune up. No problem with the speed-weighted tuning knob.

As you can see I absent-mindedly tuned it to the GM8RBR beacon on Skye on 70.100 (almost). That is a beacon I rarely hear, and up it came - say 529 report. Then, emboldened I tuned it to 70.000 to see if I could hear the Buxton beacon which is usually even harder to hear. I mis-tuned slightly but I could see it on the panoramic display so I tuned to one side and there it was! Also 529 at peaks but never inaudible.

These are very simple tests - I will have to carry out some more investigation.

Power output at full power seems about 40 watts as opposed to the official 50W. I bet that will get some comment, but as I intend to use it as a linear driver it is fine by me. I only need 10 to 15 watts for my purposes.

No time yet to check it out on the lower bands as I am getting ready for the RSGB 4m UK Activity Contest this evening.

I will post a detailed review in due course. However, a couple of things strike me. One is it is very light. It is the width of the FT-450 (which you can see above it), taller to fit in the display screen, and yet it feels much lighter. Not much circuitry needed for the SDR rig, so I guess most of the weight is PA section and tuner.
Secondly, the receiver is amazingly quiet. I know that SDRs are famous for this. My Flex 1500 was delightfully quiet, though my Fun Cube dongle is not so peaceful. Does this disguise super efficiency or some deafness issue? We shall see.

Anyway so far I have only worked 1 station - Scott, MM3LSO. 3 km distant. IO85wu to IO85wu.

More later.

73

Jim
GM4FVM

Friday, 25 March 2016

Operating "holiday style" from Portugal.

Hello everyone from sunny Scotland. Well, it is now.

After a very blustery wet winter we have unusual plants flowering in the garden, and our regulars are in bloom early. It really has been miserable. Never really cold, with very little snow, but mild. The warmth has brought out the plants by keeping the frost away. But long, dark and wet. So it was time for a short break in Portugal.

I usually take the Yaesu FT-817 on a trip like this. This time I took my usual mixture of bottom-fed telescopic whip antennas, plus a magnetic loop, some co-ax and a microphone. Added to that were the power supply for the rig, data interfaces and wire for counterpoises. Quite a pile of gubbins for the airport security to rummage through, with the added joy of a PC power supply and my own medical equipment with pumps and tubes in there too. 9 Kg of shoulder bag in total - if the plane had made a heavy landing the whole lot might have come down on top of me.

I managed to get the 817 working in data modes after a short while, though I needed to do quite a bit of setting up. Here it is pictured in temporary pose, with not quite vertical antenna and just a rough arrangement to keep the antenna away from the concrete wall. Later I moved it into the open and got everything vertical.

The two boxes are the data interface and CAT control. These are not big or heavy, but the associated wiring is pretty bulky.

I do not use the 817 with the laptop very often, and one reason is the very noisy power supply which came with the computer. So last year I bought a new battery for the laptop and I tend to run it on battery. If I charge it from time to time while I am on transmit it runs for a couple of hours.

All this disuse makes for a long set-up time, matching the 817 to the laptop..

Then two issues arose. One was that after installing Windows 10 on the laptop some time ago, the time correction software was not working. This was Meinburg. It does work with Win 10 but I do find it a tricky thing to set up so I decided to ditch it and install Dimension 4. Luckily the hotel wi-fi was only €10 for a week so no problems there, and I needed the wi-fi for other things anyway.
You can get away without adding a time synchronisation program if you are careful to keep the Windows clock up to date, but I reckoned it was worth it to take one thing out of the calculation when everything goes wrong. Just as well; another amateur operating nearby was a good 20 seconds out and not being decoded by anyone (even me).

Strict timing is needed for WSPR, but many other modes are a bit more forgiving. It took me a while to set Dimension 4 up and then I had to plough through the list of clocks and remove all the ones outside Europe. You do not strictly need to do this, but the shorter the journey the impulses have to make the more accurate they will be (yeah, like the internet would let you know how direct the link you have really is!).

Timing sorted, I discovered that I had forgotten to bring a USB sound card. I thought that the interface installed a virtual one but I had packed the wrong interface. I usually carry a spare, but not this time. This should not be a big issue, as I could use the laptop's sound card and the audio jacks on the side of the computer case. Yes, this works but it is not good practice.

But it did not work. Ever since I bought this PC I have struggled to get audio out of the stereo jack without the same audio coming out of the speakers. After a while operating with high pitched tones coming through the speakers on every tx session, I decided to give the holidaymakers on the next veranda a break. It took a while, but an obscure setting on the laptop's sound card manager finally sorted that one.

The spare USB sound card was sitting here ready to be packed, when I got home.

OK, so I was running using the computer sound card. CAT running, rig output about 3 watts, SWR too low to measure on 20, 15 and 10m. Results - awful.

Now it was not a "radio holiday". Operations were confined to about 2 hours in the afternoon. Mostly I used WSPR. 20m was round Europe, 15m a bit better and 10m dead. The solar flux was 87, which accounts for most of the problem. Success on trips like this depends a lot on the time of year you can book the holiday. In this case, £250 for a week in Portugal direct from Edinburgh is the deciding factor. Yes, conditions might be better in May, but the price of the holiday is much higher then. And  the break towards the end of Winter was much needed.

Of course it was not all bad on 15 m one day ...

Or 20m another day ...

And then again, how do you measure success? Just setting up and getting going was fraught with problems, but that is part of the exercise. Amateurs have always enjoyed getting away and operating from "the field" to test their skills. Not that a sunny balcony in a pleasant Portuguese resort is really in the field, but I can kid myself that it is.

Just getting round Europe is good enough for me on these trips. However, one thing does nag me. The WSPR software treats complex callsigns in an unusual way. As there is only room for a 6 character callsign, those with "/"s in the them (such as mine CT7/G4FVM) have their transmissions divided and sent over two time segments. At the receiving end they are paired up again. So rather than the receiving station only having to get 2 minutes of transmission from me every 16 minutes or so, my callsign will not be reported as received until the dx station receives two transmissions from me, which might take 30 minutes to get as I am receiving for the rest of the time. They need to receive both halves of the message, not the same half twice. That could take an hour or more, or it could happen in 10 minutes. It all just depends on chance and conditions.

The statistics of all this means that it is a lot easier to hear stations whilst out /P or /abroad than it is to be reported as heard yourself. And so it proved. But it seems to be getting harder over the years. I fancy that some simple versions of the WSPR software or not equipped to store and put together the two halves of the transmission at all.  Also, quite a few stations only work in beacon mode and do not receive at all.

Maybe I am just imagining that. However one thing is for sure. The sunspot activity is now getting so low that many amateurs are going lower in frequency to find activity, leaving few around on the higher HF bands. And so maybe one day I will need to get better antennas for the 40m or 30m bands to take abroad. And does that mean even more tackle to bring through airport security?

I have been living through a happy period when taking a few whips abroad was enough. Up until now that worked. Now however I might need to think again. The magnetic loop was a bit of a flop too. Maybe it did transmit a bit better than the whip but on receive it was cloth-eared.

Ah well, at least the sun shone and the food was good.

73

Jim
GM4FVM back in Ayton

Tuesday, 15 March 2016

In praise of VHF, meteor scatter to EA and a new magnetometer.

I am in the process of writing a long (too long) bombastic, typically argumentative piece about the joys of VHF. To excuse my ramblings I am starting with personal overview, the idea of which is supposed to be that I view VHF as a segment of spectrum rather than 3 or 4 specific bands.

While I carefully hone my wafflings (or delete them to spare you all the agony) I saw this from IK1ZYW. It happens to be about 4 metres, but it could be any VHF band (I happen to think that 4m is best for this type of magic, but that is just me).

The day after Italian HAMs were allowed to use 70 MHz band again for a few months in 2014, I reconnected my transverter and erected the dipole on the balcony. I tuned the band checking the local beacon with my ears and looking at the DX cluter with my eyes: the band was open.
All of a sudden I heard someone distant having a QSO. Disappeared. QSB was very fast. Then another voice, very strong, GM4JTJ, that came back to my 5W SSB balcony signal! Hooray!

I felt like 25 years ago, when as a child I worked my first DX'es on CB channels. I kept tuning, calling CQ, tuning, trying to ignore the female voice(s) calling me for dinner. But this time it wasn't my mother's voice, it was my youngest daughter's reminder that dinner was on the table.

I walked to the kitchen, explained that a unique event was going on, an event that happens 4-5 times a year and doesn't last long. When returning to the shack I got the familiar "don't complain if there won't be food left for ya", this time thrown at me by the older daughter.

It was a funny parent-child-parent role inversion.

In the following days I came up with a quick way to explain propagation. You must have seen Stargate movie to understand it: sporadic-E looks like a wormhole opening to some random part of the world.

Now waiting for another randomic wormhole...

I sometimes feel like that when the VHF bands open. Sadly, Italian stations have not been active on 4m since 2014, so I hope for all of us that the authorities there allow 70MHz amateur operation soon.

I finally completed a meteor scatter QSO with EA2BCJ on 4 metres on 12 March. That contact has been weeks in the making. Tomas and I have tried quite a few times but it just did not happen. When it did, at 22:38, I recalled the "official" propagation for this week which stated that mornings would be the time for Meteor Scatter. When we tried it in the mornings it didn't work.

But carping aside, that was a nice one for me. A new square as well, and my first Spanish meteor scatter contact. Not that I am counting my meteor scatter countries, which I must do some day. Not too many I suspect. Thanks Tomas, you put a lot of effort into that one.

GM4PMK runs his own weather and solar observatory on Mull, and posts the results to his website. You can find it here :http://www.marsport.org.uk/observatory/index.php. As you loyal readers will know I have been using the Norwegian stackplot, and very useful it is too. But Roger's location is pretty well on my latitude, so how helpful is it likely to be for me? Answer, very helpful indeed.

Here it is, for example, for the 20 January aurora:-

The 20 January aurora started here at 16:40 so there was plenty of warning in Roger's traces. It also seemed pretty accurate in relation to the strength of the event here.

I shall still combine my magnetometer readings from several sources. But adding more sources is very helpful. I find most UK magnetometers on the Internet are either too far south or too insensitive, or both. Now I have the combined power of GOES satellites and Sundsvall in Sweden on Solarham, The Norwegian Stackplot and Roger's instrument.

Before I included it in my roster, I watched PMK's site for a few weeks and it seems very representative of what is happening here. It should also be very useful for other amateurs further south and into Western Europe. For them it might perform the same function as Rørvik (rvr) does on the Norwegian Stackplot. This is a device which seems to be somewhere near where my signals seem to be reflected from, based on experience of the results.

Anyway, thanks to Roger and thanks for allowing me to use the traces.

Just at the moment, the barometric pressure is high over Scotland. "Set fair" as the barometers used to say. Result - of course it is grey and raining here. Things may improve over the next few days. Tropospheric propagation needs no special adjustment to work it, you just need to be around when it happens. So good luck to those of you near enough to work some.

If there is any.

73

Jim
GM4FVM

Monday, 7 March 2016

Aurora comes to FVM-land

Greetings

It is not so often that the Aurora Borealis becomes visible at this location. However, it did last night.

Mrs FVM and I were able to watch the spooky light show from the kitchen window. What started as a brightness in the Northern sky later resolved itself into shafts of light. I saw colour changes from red to green to blue, though Mrs FVM did not see it in colour (which is odd as I am the one who is slightly colour blind).

Of course, watching aurora is only a distraction from playing radio. And in the resulting enhanced propagation I worked ... nobody.

I heard GM0HTT in Orkney and LA8AV on 2m SSB, and the 2m Northern Ireland beacon. On 4m I heard beacons in Northern Ireland, Skye (Western Scotland), Faeroes and Norway. On 6 metres I heard several Scottish CW stations via aurora and also Oli TF3ML.

So best DX heard was about 1425km on 6m, 883km on 4m and 849km on 2m.


I spent some time trying to set up my morse key. Sounds odd for me, but CW has its uses. I discovered too late that when I upgraded the firmware on the IC-7100 and it reset all the settings (silly me with no backup), it also reset the keyer. Thus, my backwards wired squeeze key sent dots when it should have sent dashes and vice versa. It took ages to work that out via the menus, and then the speed was 20wpm (huh) so more work in the menus. By the time I was ready to go the CW had disappeared.

Anyway, I now have a working backup for the IC-7100, just in case it all happens again.

The aurora itself followed predictable enough lines. Solarham had correctly predicted it three days in advance. However, it was stronger than expected.
Bz of -17.9 is pretty good, but the wind speed never became really fast, although it did eventually reach over 500. X-Rays were low after a morning session which produced a blip and a (related?) 6 metre Es opening.

That K number of 5 is pretty good but it reached 6 by about midnight and 7 thereafter. The ground based magnetometers took a real pounding (see later graph).

In a separate development the solar flux index dragged itself just over 100, so there was a 10 metre opening via the F layer. I got as far as the West Coast of the USA on that, but I have left it out of this chart of the Es opening which was associated with the aurora.

Of course, as some people say Es is a weather event, this could never have happened (lame joke). Please do not write to me about that comment: if you cannot see it as a joke you have no sense of humour, which will be the gist of my reply.

I even managed to spot MM3LSO, Scott, on 10m WSPR. WSPRnet says that Scott is 0km from me, because we share the same locator. He is actually about 3km away. It looks as if he was testing a Raspberry PI-type WSPR transmitter. These are very handy for testing these conditions, and several of the Scandinavian stations were using them too. The run about 10mW and they are often left running continuously, the only drawback being that as there is usually no receiver I cannot find out how I am getting out. Still, there are enough conventional WSPR stations listening to confirm reception. 2-way WSPR reports still have a special status with me, brought up as I was on old-style radio.

So that was the aurora of 6 March 2016. Nobody worked. Good fun watching it though.

However, I had a nice contact with SP9HWY on 4m meteor scatter on 5 March, and a long blether with Andy GM8OEG earlier on 6 March (on 2m FM!). I suggested that Andy should look out for a possible aurora.

The Meteorological Office suggest that we might get more aurora tonight as well. I guess it will be weaker (which might be no bad thing from a radio point of view). Anyway, here are the magnetometer readings for about 15:00 on 7 March. You can see that after last night's event things have steadied up while the auroral oval was pointing towards the other side of the Earth. We shall see for tonight. Here's hoping that someone might actually hear me.

Just think, it could be you.

So get that VHF antenna up.

73

Jim
GM4FVM