Monday, 30 March 2015

Trans Equatorial Propagation

Trans equatorial propagation, something I don't get here.

This image is from DXMAPS, and I shall add a link to the DX Maps site. It is a brilliant site. I contribute to it, anyone can watch it. It is run by Gabriel, EA6VQ. It must be a lot of work, and I think it is worth contributing some Euros from time to time in exchange for this great service. Not only can you see the spots on a map, you can also see the list of contacts. Very useful is the "ES MUF" map, which shows were the Es clouds must be located. Very helpful.

The shot above shows TEP in full swing on 6m, though it also works in my beloved 28MHz and 70MHz bands too. TEP does not come as far North as 56 degrees. These contacts are often 7000km+ - e.g. Greece to South Africa or Reunion in the Indian Ocean - quite something for VHF. All I can do is sit and watch it all happen.

There are several reasons why TEP does not work from this QTH. One is that the geometry of the situation does not extend this far North. The "equator" in this case is the magnetic equator, which is displaced from the geographical equator. Even then, I am probably too far from the equator to see the ionised clouds on either side of it. Secondly, a comparable distance South from here would be South of Africa, in the Southern Ocean. Not much activity there.

If you look at the Americas, where there is territory further South, the picture is different anyway as the magnetic equator is differently sited there - yes they do make TEP contacts from Argentina, but not as far North as we get in Europe. The magnetic equator is North of the geographic equator on the Europe/Africa axis, but further South on the American axis. So it is a mixed bag.

Recently though I saw a TEP spot on DX Maps from a station about 250km South of me. That is a lot closer than usual. He was only hearing a beacon, which I bet was frustrating for him. We do not know if it was possible 2-way and if a QSO could have resulted. However it shows that, given the right conditions, TEP can come relatively close to me.

Maybe one day there will be a TEP opening from here. Given the right conditions, other propagatiion modes could link into TEP. For instance, perhaps Sporadic E could carry my signal far enough South to reach the Northern extent of TEP. The snag is that Es occur here in the Summer (and for a few days in Winter) whereas TEP generally occurs in Spring and Autumn. So there might only be a few days each year with the potential for it to work (if it would work at all).

Other methods of bringing my signal South have been suggested as a way to link into TEP. Tropo ducting might work but since I moved here there has only been one good tropo opening in 7 years, and a couple of limited ducts. Still, it might work. Certainly in the late 1970s there were quite a few tropo openings but that seems to be a thing of the past now (climate change?). Tropo scatter might also work, but it would be VERY weak. Right now I do not have a very good 6m antenna.

And then the other factor arises. How badly do I want to gain access to TEP? You might say "move to France or Portugal". Yeah, well then I would lose most of my beloved aurora, auroral Es, Thule-Es and so forth. Auroras are less predictable than TEP, but maybe that makes them more fun. Ordinary sporadic Es are much less common here than in the South, but I value them more. Maybe their very rareness makes me appreciate them. Anyway, how could I deal with all the sun and the lack of snow, gales, and driving rain? How could I get Fig Rolls and Newcastle Brown Ale in Portugal?


So maybe I just have to accept it, I need to watch TEP going on and accept that it is not for me.

But you never know.

I seem to do OK without it.

73s

Jim
GM4FVM
Thanks to Gabriel for permission to use the screen shot.

Sunday, 29 March 2015

6metres and how I can't climb any more

OK, the 6m antenna is now up and ready to go.
Unlike my 4m or 2m horizontal antennas, this is a not a DX one. Perfectly effective, the Diamond A502HB is not exactly a high performer. It claims 6.3dBi gain, which is good for a 2 element, but not in the 3 element class. Having replaced a 3 ele on 6m with a claimed gain of 7.24 dBi, it could be seen as a step backwards.

The explanation for this is that the previous antenna was a dual band 4m/6m, and that space is now occupied by a much better 4m antenna, so 6m will have to get along with this. So the 2m half wave which was up on this bracket has been replaced by a vertical dipole on the main mast, and this rather weak bracket now has to support the 6m set-up. Why not put the 2m half wave vertical on the main mast - well I tried, but it only takes a 37.5mm mast and my main mast is 50mm.

This is starting to sound more like an edition of Peyton Place than a radio blog (reference only understood by those over 95 years old). Erm .. struggling for a more modern comparision ... more like a Twin Peaks edition. Now that shows my age too.

The Diamond antenna is often referred to as a Yagi, including by Diamond America. But in fact it appears to be based on the HB9CV design (not that Diamond say THAT). Both elements are driven and the arrangment is entirely out of the HB9CV design book. That is what gives it extra performance over a Yagi and in particular a very short boom. It only loses about 1dB over my old 3 element Yagi, and I have worked Puerto Rico on that. So it is perfect for lightweight rotators and simple brackets.

Key to the whole thing is that all the materials, except the 3 core mains flex used for rotator control, was already on the premises and therefore cost nothing extra.

OK, the 6m set up is RG-213 co-ax, two old 6 inch TV mast brackets, Conrad £50 rotator, Diamond AH502HB and two 1.25m lengths of 37.5mm OD thick wall ali mast. The design issues here are obvious. "It'll fall down", you say. These brackets held a Watson X-30 "co-linear" (actually a half wave on 2m and only a co-linear on 70cms). Now they have a much heavier load. The rotator is lightweight in rotator terms but heavy for the brackets. I have split the pole lengths roughly evenly. I had intended to have a shorter 50mm pole at the bottom - but the brackets only take 37.5mm !!!! Also, the rotator is only meant for light duty, and seeing it with a two metre long pole above it scared me. So compromise is the order of the day.

I first put it up two days ago and tested it about 50cms lower in a wind of 80kph gusts. It whipped about a bit, but lasted the wind. We do get well over 100kph gusts here. Now it is at full height. Worries are whether the rotator can take it and whether the brackets can take it.

Now here is the awkward bit. The obvious thing to have done was to leave my 2m vertical where it was and put the Diamond under the Sirio 4m vertical I have. It is supported by good strong T and K brackets, well bolted into the wall. And why not? Because I have lost the ability to climb up and work at the height of the Sirio. It was me who put that antenna up there, but that was years ago and now I cannot reach it. Here is a photo of my scaffolding tower which I previously used to reach the Sirio brackets...
The scaffolding tower is a neat thing. In this picture the working platform is about two rungs (about a metre) lower than needed to reach the top bracket. But this week I could not work with the platform any higher. So basically I cannot work on this antenna any longer. I am toying with the idea of getting someone to move the top bracket down below the bottom one, and maybe then I could manage.

I do not know how I lost my head for heights. As it stands, the Diamond 6m beam is now about 50cm below the ridge tiles of the roof. That might do for meteor scatter or Sporadic E, but it rules out much tropo. It really ought to be up in the clear on the same mast as the Sirio, but just for now I cannot organise it.

In a bid to prove that it all worked, I used the Diamond to put out some calls on 6m meteor scatter. I worked 2E1IIP and GM6NX - both on tropo! (To be fair, they were not working anyone on meteor scatter either, so propagation was not great). We shall see how effective this proves to be. Either I need to get over my sudden loss of ability to work at heights, or I need to get someone in to change things. And then again maybe the wind will blow it all down anyway.

Or a second tilt-over mast?

73.

Jim


Tuesday, 24 March 2015

Meet the handhelds

I am a tutor and examiner for the UK amateur licence exams, but the local clubs cannot be bothered to allow me to run courses. But for a while I did and one candidate arrived here to do his morse familiarisation (me teaching someone morse is an interesting idea). He looked around the shack in amazement and said "why do you need five radios?".

Good point. That stumped me. There is an explanation of a sort, and more of that later. What he did not know was that I have four more in the shape of handhelds.

Before I had the current four I had Yaesu VX5 and 6s, (two band 144/430 MHz, and one had 50MHz as well, not that 50MHz was very useful) and a Wouxun KG-699E 70MHz one. Years ago I started with a Trio (Kenwood) TR2200 - 1 watt, weak, deaf and with hopeless Ni-Cad batteries. The TR-2200 was less of a hand portable and more of a "luggable": bigger and heavier than a Yaesu FT-817 but with just six (expensive) 144MHz crystal controlled frequencies. I also had a hand portable in the 1970s, the name of which escapes me. I think it was called a "Ken" or something. It was equally useless. It was not until the 1990s and the Yaesu VX range with lithium batteries that they became practical for me.

Lined up here like something out of a police drama, are the four suspects:-



They are, from left to right, a Baofeng BF-888F, a Baofeng UV-5R+ Plus, and two (yes, two!)  Wouxun KG-UV6Ds. The Wouxun on the extreme right is in its desk charger.

The Baofengs are really a pair. Baofeng, now renamed Pofung (surprising move that), make radios that are ... value for money. In this case, £10 and £30. You might not expect much for that money, and not much is what you get. They are OK. In many ways I respect them more than the Yaesu VX5 and VX6 that went before them. The VX6 is now £200, and I cannot see what use increasing the price by a factor of 7 over the UV5-R+ brought me.

The 888 is a basic thing. It has no display and so you have to program it using a cable. There are 16 channels available to program in its 400-470 MHz range. It runs about 2 watts max (a little less maybe). It comes with a lousy antenna - but all these things do. First step in cheap handpoartable land - replace the antenna with a Nagoya one. All parts like the antenna, mics, power leads, spare batteries for cheap handhelds are easily and cheaply available from Hong Kong via eBay. Including must-have Nagoya antennas.

I bought that 888 to work with the UV-5R+ Plus (yes, that is plus,plus according to the front panel). It can also listen on most of the licence-free European PMR frequencies. Not all because it does not have the right steps, but most. Of course, it would not be legal to transmit on those frequencies with this rig as at 2W it is vastly over-powered. Also, it has that demon of things, a replaceable antenna. The PMR spec is for 500mW and fixed antennas - and PMR rigs cost four or fives times as much for a lower spec. As Granny Edgar used to say "The World is ill-divid".

Anyway, apparently some people use cheap rigs like this to tx on the PMR frequencies, but I know NOTHING about that. I can use it legally on the 70cm amateur band, and listen on PMR. My plan was to use it on the local GB3BE repeater, only to find that although BE gives its CTCSS code for a 118.8hz tone every time it identifies itself, it does not accept the tones. It only opens for a 1750hz toneburst which the 888 does not have. So that idea is out the window, and the world is even more ill-divid than I thought. But at £10 do I care? No. Apart from that issue (which is not the 888's fault, as it never claimed to have a toneburst) it works fine and for the money I have have had no problems.

The UV-5R+ was a replacement for the Yaesu VXs. I have a 12V back to replace the battery for mobile use, which is what I did with it until the Wouxuns arrived. I find that the only speaker/mics that sound at all good are the Wouxun branded ones, and that was what I used with it. I might say that I just listen when mobile, and rarely transmit.

The UV-5R is a good rig, runs about 5W max and has a frequency range of 136-174 and 400-480MHz. It has a 1750hz toneburst as well as the usual CTCSS and stuff. Unlike the 888, it has a display screen. As it has a display you can in theory program the memories by hand, but I suspect that using a computer makes it much easier. Some of the UV-5Rs I hear sound a bit strangled, so using a speaker/mic is a good idea. It also has an FM broadcast receiver built in which can be set to mute when the squelch opens on the ham side. Note: replace the antenna!

Not much to say about the UV5-R. I used it sometimes as a replacement shack rig when the main 2m FM rig went belly-up, and the (two) replacements also failed. Provided I used the Wouxun speaker mike, it was fine. One more thing it will do which the VX5s etc would not (after the dual FM/Ham radio trick!) is that I can program it for use in North America, as the Yaesus sold in Europe were limited to 144-146. And of course it will listen to some PMR channels.

The UV5-R+ is now the rig I use in my workshop over the garage where I build model trains, DCC control and interlocking, and the like.

Now, the two Wouxuns were bought separately, but always with the idea of reducing the handheld count by one. Which never happened.

It went this way. When I went mobile I was taking the UV5-R for 2m and my single band Wouxun KG-699 for 4m. That was a pain as I had to stop the car and swop rigs to change band. So when the Wouxun KG-UV6D dual band appeared (range 66-88 and 136-175 Mhz) I bought one to use mobile. The plan was to sell the Wouxun KG-699 I had (which I did), and sell the UV-5R+ (which I didn't as it forms a pair with the 888). Then I could use the dual band KG-UV6D in the car and for general handie type purposes.

That UV6D rig, rig "A", lasted a week before I dropped it on a concrete road surface and then the next day into our garden pond. When it came out of the pond it would not work, the display was blank and there was a leaf floating in water inside the display. That was maybe looking  bad for the rig, so I phoned the importers who told me that it was beyond redemption and I bought another one (rig "B").

Later I looked up the spec and Wouxun claimed that the UV6D can survive brief immersion. As they are intended to be used as site radios, so they are built to get wet (though dropping into a pond is not really expected, and it did take a few minutes for me to wade in and retrieve it). It does not claim to be "submersible", but maybe it would recover. So I carefully stored rig "A" without the battery in a airy place, and left it very much alone to see if it would dry out. After a couple of weeks I reconnected the battery and sounds came out but the display was dead (but it had dried out). After another couple of weeks I tried again and rig A came to life and has never looked back. The leaf dried out, turned to powder, and fell out again. I doubt if that was good for it in the long term, but we are where we are.

So I have two.

Rig A lives in the car and is now my mobile rig. That is probably a good thing as the little SMA-type antenna sockets do not take well to repeated unscrewing. I use a pigtail bought on eBay so when I want to take it out of the car I disconnect the PL-259 end. You can see the pigtail in the photo. I can take it out if I am leaving the car in an exposed place (not that car crime is a big issue out here). I have a 12V battery replacement back for it so it works on the car DC supply.

Rig B is a shack rig, used for portable, general signal generation and so forth. I don't need two, but I have two, so there you go. Two batteries is a handy arrangement.

Performance-wise the Wouxuns are a step above the Baofengs. Audio quality is excellent, but then again the Wouxun rigs are about £80 for this model. The receivers are more sensitve and the harmonic radiation is vastly better. I wouldn't connect a Baofeng to a linear amplifier but I have done with the Wouxuns. The display is clearer, the rig sits more comfortably in the hand, the controls work more smoothly. Man, the Wouxun is the handportable-lovers handportable. After the KG-699 (which was excellent) I had thought that the dual band UV6Ds might be less effective, but they just work fine.

The antenna supplied with the UV6D is not quite as bad as some, certainly better than the KG-699 one was, but I would replace it if you can. The usual Nagoya does for 2m and a Garex (now Spectrum) wavy-thing does for 4m. I also have a 4m bottom loaded whip which is quite good. In the car I need a diplexer and two antennas for both bands.

OK, so these rigs are value for money. They work. The programming software can be a pain. You can find it in various places such as the "409 Shop" website (I bought my first Wouxun KG-699 from 409 Shop and bought various bits over the years and they are reliable suppliers in my experience). The software gets tricky with the UV-5R+ which has various versions and not all the software works with all the rigs. Luckily I bought a generic programming lead with a disc enclosed which is for "UV5-R New" which works with mine. Trial and eror may be required. I believe that "Chirp" works well in Linux and it will program almost all of them.

When it comes to programming leads, quite a few of them have "fake" Prolific chips in them. The driver discs in the leads will work, until Prolific update the driver via Windows update. Naturally, Prolific are not keen on having their chips ripped off, so they have every right to update their software to a version which stops the fakes working. However, in Windows 7, at least, you can assign the old driver to a specific device (select "chose a driver from a list" and juggle them about). That will work until Prolific issue another update. Works for me anyway.

So, for all these rigs, they work well as far as they should for the money. They might even survive dropping onto concrete surfaces and into ponds (but I do not recommend it). They are programmable (fiddly) , you can find accessories cheaply, there are good speaker mics (well, Wouxuns mics anyway) and they take well to good antennas. What is to complain about? Not much.

But I think that four handhelds is enough.

73

Jim

Thursday, 19 March 2015

Is the IC-7100 a good rig?

I have an IC-7100. All of those 45 aurora contacts made on 17 March were made using it.

I am asked would I recommend it. Well, yes, if you know what you are letting yourself in for.

Plus features are many - small size of the control unit, nifty touch screen controls, reasonable price, RF DSP, 4m for Europe, good frequency stability for data modes, USB lead to PC allowing direct audio in/out for data, DStar, coverage up to 70cms, ....

(EDIT - by 2018 I have mellowed, and now accept it as a good rig - http://gm4fvm.blogspot.com/2018/10/my-grudging-appreciation-of-icom-ic-7100.html )

The snags I have experienced and my solutions are - low output powers on SSB (needs separate microphone with compressor), "clicking noise" (not a big thing, I am ignoring it), RF getting back into the control cable (use a short screened ethernet cable CAT6 or higher), deep cut on AGC a problem with QRN (electric fence problem in my case, turn AGC off).

OK, there are some problems, which are capable of being fixed. I complained to Icom about the clicking noise and they said they were looking into it and that they would reply with a solution soon. They did not reply. Also, the local dealer said the same thing and never replied. We are on our own with this one, but it is better just ignored.

For SSB and FM I use an Adonis 508 microphone set to low compression. That allows me to get the power up to the stated outputs, more or less. When I tried to raise this issue on the various sites, I got lectures about the difference between peak and mean power on SSB. Look, I know about that. Yes, I do have a peak reading power meter. There is just no way my 7100 can run the stated peak power on SSB using the internal compression and the supplied mic. But with an external amplified mic and the internal compression turned off I can get good results. And I DO  KNOW ABOUT THE DIFFERENCE BETWEEN PEAK AND AVERAGE POWER.

EDIT - there is a mod for this which I have not tried, but I know some people who have. There are in fact two mods here, however I believe that only one of them should be done (the soft one looks best to me) - see here http://gm4fvm.blogspot.co.uk/2016/02/ic-7100-low-ssb-output-surgical-solution.html

On data modes it is a triumph. It runs full stated power for ages and does not complain - like a meteor scatter contact with Italy lasting 3 hours! I have used it on FSK441, WSPR, JT65, JT9 PSK, JT6 ... all fine. No problem there at all, which makes the SSB performance a bit disappointing. But I fitted an external mic and I am in business on SSB too.

I don't use DStar so I cannot comment on that. Receiver wise it is OK, but I mostly use 12m and 10m on HF. I would guess it is OK on 80m and top band, but at this price it might not be brilliant in adverse conditions. I bought an LDG IT-100 ATU which is great but I have not used it much. My IC-7100 runs fine on 2m and 70cms.

It might be helping that my IC-7100 generally runs into linear amplifiers, which may cover up the low SSB power issue - on 6m an RM VLA150, on 4m a TE Systems 0610G and on 2m a Microset SR200. With that set-up - it blasts along.

So, I am happy enough and I would not want to put anyone off. But it should be better on SSB transmit. If the touch screen works first time it seems to be fine, in the shack anyway. Not sure how it would work portable or mobile where it would get strong light hitting it. The control unit stays steady if you extend the stabilising feet behind it.

OK, I am peeved to buy a whizzo rig with an internal DSP compressor, and then turn the internal system off and have to use a 1970s technology outboard mic. But after 18 months I have got over that one. It is OK. I wouldn't put anyone off. And for Europeans (or Africans or Asians in some places!) looking for a 4m/ 70MHz rig, it is a reasonable choice.

Finally, a recent firmware upgrade to the DSP and audio might have had the effect of helping the AGC dip issue. It seems better, but it has not gone away. I would suggest that you live somewhere away from electric fences.

Jim
GM4FVM

Wednesday, 18 March 2015

Aurora finale & propagation predictions?

Well, it is the day after St Patricks Day.

The GOES magnetometer graph of the event is shown, thanks to the Solarham page. The scale has had to be lengthened, as usually it does not extend much beyond the bottom of the daily sine-wave type variations. you can see that the magnetic fields were heavily disturbed.


The second phase of the 17 March event went on after midnight, but I finally ran out of reserves about 23:30. After that US and Canadian amateurs did good work all night. I did manage to work a couple more stations, G4ASR and G4RGK before pulling the big switch at 23:44. The beacons in GI were still coming in and I could hear traces of signals on the calling frequencies, but I was, basically, banjaxed.

At about16:00 the next day the HF bands are still battered after the shock. My favourite 10m has been fairly well closed all the past 24 hours. It will return eventually. There have been a few more auroral contacts in Europe this afternoon but I suspect this one is now over.

OK, I have to say that a successful aurora for me usually invovles five or six stations. Typically that is a couple of GMs and maybe an LA or an OZ. Sometimes something exotic like Faeroes Islands or Jan Mayen spice it all up a bit. So the St Patrick's Day event 2015, with 45 stations worked, is a big deal. Even then I am not entirely happy. If I had been able to use 6 metres I may have joined in a trans-Atlantic opening (though that seemed further South). The stations I did work were not very evenly distributed, with a lot of G stations, several EIs, OZs and PAs. That pattern was actually quite localised. There were no OHs, DKs or SPs heard here. I cannot complain though.

The question arises, can these events not be more accurately predicted? Frankly I would say "no". I know that there are all sorts of predictions published, but they never seem to me to be able to avoid giving many "false positives". In other words, they warn you of things which do not happen.

Other predictions (and I will not say whose, but they call themselves a National Radio Society) are so bland as to be useless. "It is not Summer yet so don't expect Sporadic E" (obvious, and occasionally wrong too), "There are no meteor showers predicted, so you could use random metor scatter instead" (duh!), and "the weather looks good so maybe there will be some tropo" (yeah, like you care about the weather where I am ). If those are predictions, I could do without them.

I do my own predictions. I watch Solarham (I will post a link to the site address alongside this post). Then I look at what is predicted there, interpret it my own way, and act accordingly. And I too get a lot of "false positives". But I was ready for this CME and aurora so I am happy enough.

Solarham do not predict radio events. They describe the solar situation, and you have to work out the radio effects yourself. Fair enough, I like to use my brain. This is a scientific hobby after all. But if the great US agencies like NASA and NOAA get caught on the hop by the St Patrick's Day event (they predicted a "possible glancing blow"), then my little string of seaweed can hardly predict the weather. I believe that nobody can predict the random events on a complex system like the Sun, and then accurately transfer the likely effects across space to Ayton, Berwickshire.

When is a "false positive" OK? When it is MY "false positive". That way I only have myself to blame.

73

Jim
GM4FVM

Tuesday, 17 March 2015

CME shock wave and 10 metre condiitions

12:00z 170315

A Coronal Mass Ejection shock wave reached earth in the early hours of St Patricks Day (17 March 2015). Nothing too special about that but they have been rare of late.

On 10m my daily routine of WSPR work has shown strong signals from VK and Spoadic E arriving from Europe. A bit of a surprise was hearing PU3WSF before mid day.


There was probably an HF blackout about 04:00 when the shock hit, and now we have the results on 10m. It depends how the stream of particles arriving from the Sun are polarised as to whether we will have an aurora or better conditions. If the "Bz component" is positive, not much will happen. Right now Bz is -2.9 and the solar wind speed is over 600, both necessary conditions for an aurora. But for me at 56 degree North and 2 West it usually takes a larger Bz number at, say, 15:00 up to midnight, for this to work.

 However, we will see. The Sun has a habit of surprising us. Maybe the negative Bz will shoot up, maybe not. Maybe 2m will open with auroral signals, maybe 10m will have more sporadic E, maybe none of the above.

I picked a bad time to be off 6m if it does get good.

73
Jim

Saturday, 14 March 2015

Aurora and Norwegian Magnetometers.

I am posting a link on the side bar to a stack of Norwegian magnetometers. When they go negative we know that auroral propagation is possible. The one I watch is Rorvik ("rvk"). Thanks to Gianfranco, now IU1DZZ, for giving me the link in the first place.

Here is a screenshot of today's magnetometers. There is a bit of disturbance - I wonder will we get aurora..


Worth keeping an eye on if you can access auroral propagation, and it gives warning of HF blackouts too.  These are the relevant ones for me; you can find the Boulder Colorado one and the Sundsvall one in Sweden on the SolarHam pages.

Jim