Thursday 28 April 2016

BBC Radio 4 In Science, The Culprit, and a taste of Summer at last.

I have identified the culprit for my computer crash. Here it is:-
A Toshiba 2 Gb storage disc, marked "Backup" in my complex naming system (other imaginative names on others are "Old Backup" and "1" and "2").

It has almost died. Strangely, it shows up as faulty, but when I scan it to fix it, it shows up as healthy. Which is where the problem of finding the issue got stuck.

To its credit it took a system image of the computer and then fired it back, which fixed the problem completely. Then it caused the PC to freeze and crash so it is, as they say round here, "deid". So it was the problem, and the solution as well.

I think we have to learn from these things. The importance of backup is easy to forget. Also, have a spare machine around, or at least one you can borrow, as otherwise you are QRT until you can fix it. In a cruel reversal, I am recommending backup discs, which were the cause of the problem too. That is what I learned at school to call "a paradox".

Everything is restored - even my accounts and, most important, my VHF squares worked database. Over the past 20 years I have had about 5 or 6 incidents where the whole system has gone down thanks to hard disc failure, plus a couple of spectacular power supply failures which put spikes into discs. This has been the easiest to restore and nothing got lost but it all just shows how quickly we can be engulfed in a panic. Despite it all, I am not about to go for cloud storage, not with well over 10Gb of material.
----------
I am a keen listener to the BBC "Inside Science" programme. Well, I take the podcast. I hardly listen to live radio broadcasts now apart from Classic FM as I work in the kitchen. I consume hours and hours of podcasts and downloads.

A couple of weeks ago "InScience", as trendy listeners call it, featured a piece on the QB50 satellite project. Basically this is a plan to launch 50 cube sats to examine the Earth's atmosphere at heights above those which can be probed by balloons and below the normal orbits of existing satellites.

The point is that existing scientific satellites are in orbits which are long lasting (or indeed more or less perpetual) to give them the lifespan to conduct their research. It would be tricky to put one of these into a lower orbit as it would be slowed down by the atmosphere and eventually burn up on re-entry.

The QB50 ("Cubie-fifty") project envisages the launch of 50 small cube sats which will be regarded from the start as sacrificial, having lives of about 3 to 6 months or so. However, they will be small and cheap but still capable of trying to investigate the atmosphere above 100km. The main target for study is the thermosphere (technically from 85km up) and it includes the E and F layers of the ionosphere. There is enough atmospheric density there to cause the orbits to steadily decay and the cube sats will eventually burn up. This is not quite the disaster it would be with a full sized satellite.

This is (of course) above the troposphere and therefore above the influence of the Earth's weather!

The upper limit can be deduced by the International Space Station, which orbits as low as 330km and has to be periodically boosted by rocket firing to stay aloft. There are some satellites closer to the Earth than the  ISS but they have to be carefully designed to stay aloft and so this is the "grey area" which is largely un-researched.

Basically, the ionosphere between the bottom of the E layer to the top of the F2 layer. Interesting (to me anyway). The D layer can be explored by balloons.

It will be interesting to find out what QB50 discovers up there. They have mass spectrometers which should help pin down the composition of the layers more accurately than we know at present. This is the key area for our radio propagation yet we know very little about it. The broad composition we have deduced, but the fine detail is missing.

As they say, this region is laughingly called "the ignorosphere" as there has been such a small amount of research done there. 

You can find the podcast to download as an mp3 file, or listen to, here http://www.bbc.co.uk/programmes/b0766g8g. As for the piece about refuelling on the Moon, well, we will see! And on the later piece, we did have a hydrogen storage device in a solar and wind powered "eco-house" in the village. A lot of the residents were not keen to have a store of explosive gas under pressure in a garage. In due course the garage caught fire and was destroyed - after the hydrogen storage plant was removed! How strange!
----------
There was a Summer-type Sporadic E event here today on 10 metres. Hooray! 86 WSPR spots from round Europe on Es and one from Reunion Island which would be F layer. Nothing on 6m here yet even though certain other lucky readers have been hearing 6m Es. Grrr.

It is great to have signs of Summer. We need it. I went out this evening (28 April) and took a photo of the orchard where the tender apple and pear buds are forming. They, and the rest of our kitchen garden, need a bit of light and warmth just now. The photo below shows what a late April (almost May) evening looks like in Bonny Scotland.
Yes, it is a colour photo.

It is still snowing as I write. It is due to snow all night. Ah dear.

Keep warm.

73

Jim
GM4FVM

Tuesday 26 April 2016

Silence - what we all dread

This week's radio tasks seemed easy. Take a better photo of the IC-7300 for the last posting (below). Get the CAT reconnected to the FT-817 which is now on VHF. Then finish tidying the shack.

So I was just about to get the 817 sorted and I had plugged in the USB plug to it's interface when ...

CLUNK.

Followed by the gentle sound of a fan gently spinning down to zero rpm.

And then silence.

The computer had crashed.

I can cope with this. Backups, repair discs, installation discs ... all ready. Erm, no. Hard to fix when I cannot find what is wrong.

I spent a day and a half trying to pin down what it is. First it seemed to be the relatively new main hard drive, then the equally new outboard back-up drive. If I plugged the two together nothing worked, separately they both seemed fine. Windows said I must check the discs but chkdsk showed all fine. And Windows kept pointing to a "corrupt volume" with a name which meant nothing to me. Or it just refused to load, saying that there was a file reading error.

Where is drive ? anyway?






Deleting something you cannot find is a problem. All the volumes were showing up as healthy, all the drives were working and yet this odd corrupt unfindable file was messing everything up.

So there was nothing else for it but to draft in my work computer which is usually kept strictly separate from the one that runs my business administration and works my data software. It then took over a day to get all the software onto the work computer (and I am now running the risk of it packing up). I had to borrow a display board and a USB-3 board from a third computer but we are going again now.

I need to try various things related to clearing off discs and re-formatting them. Meantime at least I have data modes running again (not that there is anything to hear). There was a 6m opening on Sunday which did not come this far North, though there was some Sporadic E on 10m during the same event.

I have lost very little data (I think). Last year's accounts - but I had already printed them out ready for the tax man. My database with my VHF square totals on it - well maybe. I have an image of the hard disc which should bring these back. Everything else is secure I think.

Setting up the data modes on a new computer was a tedious business. But it is done and once I get everything fixed I can revert to normal with a backup system ready. My rigs all run without computers now (!) provided I am prepared to sink to the unspeakable depths of using a microphone.

Ah dear. After discovering that this computer does not have Photoshop, and then finding that Photoshop did not like the way the virtual memory was configured on it, I finally made the new version of the IC-7300 photo.
What a palaver. A lost weekend and it is already Tuesday.

I still have not finished cleaning the shack.

73

Jim

Friday 22 April 2016

Icom IC-7300 review

Here is an SWR graph taken on the IC-7300 of the SWR curve of my 10m Gainmaster 5/8th vertical dipole. I think this photo says a lot about what the IC-7300 can do, and I thought my SWR was worse than that up the band ...
You can see at the bottom of the screen that the SWR starts off at 1:1 at the bottom of the band. The little blue bars start very small which equals 1:1. Then the SWR increases gently as the frequency goes towards 29.1 but stays below 1.4:1 the whole time.

All I wanted was a rig, but the Icom IC-7300 is a multi-purpose shack tool as well.

This (very long, sorry) updated posting is my opinion of this rig after I have owned it for about four months. I may change my mind about some things, but I have tried to assess it in as many different situations as I can. Now is the time to set out what I have found to date.

It is not a technical review. It majors on the operational features and the experience of using it. You can find pictures and reviews elsewhere that cover the details.

I have heard a few comments on this rig from local amateurs. Generally they just rate it as if it was like any other rig from the "big three" manufacturers. On that basis it looks fairly ordinary to them, but they are not taking into account the fact that this is definitely not an ordinary rig for the big three. This is the first rig from them to use Software Defined Radio (SDR) architecture. Therefore it needs to be viewed in a slightly different light.

My comparison is based on my experience of recent rigs, Kenwood TS-590, Yaesu FT-897, 817, 450 and Icom IC-7100. For the SDR features I am comparing it with a Flex 1500 and for receive a Fun Cube Dongle.

1) Physical Appearance and Ergonomics

Well, it looks small.

In this category I am comparing it with my FT-450, which is half the price but has a much reduced range of features. At 240mm across the front it compares well with the 450 which is 16mm narrower, and the 7300 is 17mm taller than the 450. This is probably to allow room for the IC-7300s touch screen. The depth of the main rig excluding the knobs etc is 235 (7300) to 210 (450) so these are broadly similar. When it comes to weights, Icom says that the 7300 is 4.2kg, while Yaesu say that the FT-450 is 4.0kg. So there you have it, a "small" desktop rig, just a shade bigger than the FT-450.

There is a basic handbook as well a huge tome (173 pages) on the data disc supplied with the rig. As Mr Rothwell my Latin teacher used to say "Read, mark and inwardly digest the entire document". Who ever had a Latin teacher? I am a real posh old timer.

Is this a mobile rig? It seems not, but the distinction is what we make it to be. I used to drive around with an FT-101 sitting on the passenger seat beside me. 101s were much used as mobile rigs, but we do not think of them as such now. The IC-7100 is a modern "mobile rig". It has a modular connector for a mic plug and a 3.5mm key socket. The IC-7300 has a round mic plug with a good old knurled ring to screw it in and a quarter inch key socket. Is this a good way to judge which market rigs are intended for? Apparently so. It seems that rig designers use these as clues as to which market the rig is made for, so vastly expensive rigs like the FTdx9000MP+(Plus) have round mic plugs - no doubt for a ridiculously expensive headset to match the Radio Master's leather chair.

I have an IC-7100 sitting beside an IC-7300 and the only problem I have with that is that the same mic plug and key plug do not fit both, which is an inconvenience. I couldn't care two hoots what market my rig is destined for but the IC-7300 comes with a hand mic with a round plug. And that is a very good mic, more of which later.


Right bang in front of the 7300 is that 4.5 inch colour touch screen. 25 buttons and five knobs greet you as well. That is more than the FT-450 which has 24 buttons and four knobs. The touch screen gives you loads more options than any combination of knobs can do.

For example, with the 7300 all I have to do to change the output power is just to press "Multi" and up comes a section of screen with "RF POWER" highlighted, a figure for the current settings (32%) and a bar graph showing the level visually. Then all I have to do is to turn the multi knob and push it in when it reaches the right level. With the FT-450 you press "F" for a long time, turn the unmarked knob on the left through 62 options until you reach "RFPOWER", press briefly (too long and it doesn't work), turn your power to the level indicated by the numbers, press the unmarked button again, and then press "F" for a long time. If you are rash enough to try to transmit when you have "RFPOWER", or the % figures, selected then the FT-450 refuses to play ball. The IC-7300 allows you to set the power as you transmit, which is very handy for setting up linear amplifiers.

OK, this is just an example of Yaesu's ... interesting ... menu system. But there are loads of such examples. With the IC-7300 you just press the touch screen, for example to change band or to switch to the 7 simultaneous bar graphs showing, for example, S-meter/Power Out, ALC, Compression level, SWR, input current, supply voltage and internal rig temperature. And it shows all seven at the same time as showing the mode, filter setting, memory/VFO selection, time, frequency, as well as the (in this case slightly shrunken) waterfall and spectrum display. The Yaesu 450 tries its best, but it is a rig in a different class, with its white block characters and cranky controls.

So you can see why I feel that simple comparisons make no sense here - the IC-7300 is just different. It is a bit difficult to picture this.  As you know, screens like this do not photograph well. But here goes ...

Click on it to enlarge if you need to.

Clearly Katy the cat has been inspecting the rig just before the photo was taken.

That photo is in meter mode. If you do not need the meters while you are working, try scope view (all you do is press "Menu" and select the view from the options on the touch screen).

Why all the fuss about the spectrum scope?
Here you can see DO7ES on the waterfall. He is on 10m JT65, though of course it could be any mode. The waterfall and spectrum scope allow you to look and the see variable amounts of the band at a time. You can set it from plus/minus 2.5kHz of the band up to 500kHz. There is also a fixed mode which you can specify and which I use on 4 metres to cover the entire 500kHz of the band. Once you see a signal you just press the screen and the rig will QSY so that you can hear who it is.

Several rigs have spectrum scopes, but not at this price. And it is "real time" - you do not have to scan it.

This scope display is the real reason I wanted to use an IC-7300. I had a similar display on the Flex 1500 which I used both on its own and with a transverter. The Flex display was a bit limited by the software (!), but within those limits it worked pretty well. But the Icom seems to have got this down to a fine art. Yes, the display is small (but see under computer operation) but it seems to give me all the information I want. This is heaps better than the Flex 1500, it runs 100W instead of 5, has an ATU, touch screen and everything else, AND it can be run "stand alone". The Flex needed a big computer to drive it.

When it comes to ergonomics, for me, the touch screen blows the rest away. I can sit and watch for dx, or even watch while I am rag chewing or working another dx station. I can see them appear on the screen. Touch the screen and you are there on frequency.

You can set the screen for mostly spectrum display or mostly scope, or mostly meters, or an SWR graph (which you do have to scan of course; it is the one at the top of the article). A function button gives you another screen for turning on and off the noise blanker, AGC, pre-amps and attenuator, compressor ....

Some of the other settings are controlled via a button under "Menu" marked "Set". Here we get off the pictures and graphs and get back to good old menu settings. So I had to go in there to set things like (under "Function") the dial turn control and (under "Connectors") settings for using the USB connections for data, and again (under "Display") to adjust the display brightness. These are rarely used things and I do not mind diving into menus for those. What I object to on other rigs is delving into complex menus for everyday adjustments like power level.

The general appearance of the rig is something I find appealing. I understand what someone meant when they said it was "too black" (was that Ali G?). The glossy plastic surround on the front panel does look a bit "naff", like a 1970s music centre. Who cares? I sit in the gloom anyway, and all I look at is the touch panel.

I am ashamed to admit that it took me a week to spot the "P.AMP/ATT" button underneath the pass band tuning knob, as I was busy controlling everything from the touch screen. Some of the buttons are duplicated via the screen. Yes, it does have a pass band tuning knob, a strange concept in an SDR. I have yet to use it much but I guess it would be good on HF bands.

It looks like it is a "desk" rig and not a "mobile" rig. Those little styling touches (which we didn't understand) like the freely rotating finger button on the VFO knob. Ahhh.

On the back panel there is not very much to see. No 6-pin miniDIN for data modes but you can use the 13 pin DIN Icom standard mega-bruiser. Also present is their CI-V socket. There is an ATU socket which seems to work with my LDG ATU, but I have found the in--board ATU to be completely up to the task. That ATU socket could be used for automatic long wire tuners of course. There is one (just one) SO-239 socket for RF - but unlike someone else, just having one socket is not going to put me off. I have an antenna switch and several duplexers so I do not really need two antenna sockets. Then of course the USB socket for your own lead (they do not supply one). Finally the up-market key socket and a couple of audio bits and bobs.

So lets sum up the physical appearance and ergonomics. It is a neat little thing which uses the touch screen to allow you easy access to all sorts of things. That puts it into a different class from most other stand-alone rigs, so comparisons are not easy. I paid just under £1000, which I reckon is a bargain.

2) Actually using it.
That supplied fist mic gets rave reviews from people I have worked. It is a total contrast to the lump of dog-doos that came with the IC-7100 (which I believe they have now changed for some slightly better slab of coprolite). You could just use the supplied mic for the 7300 for the rest of the life of the rig.

Being a desk mic person I have added one of W2ENY's bargain desk mics (under £50 delivered). This turned out to be a bit heavy on the bass response so I delved into the "Tone Control" settings to find that the options are a bit limited. There are "TX Bass" and "Tx Treble" settings and I got the result I needed without going further. It lacks the multiplicity of twiddles possible with the TS-590 and so forth. I don't really need a graphics equaliser at this price, but it did seem a bit restricted. However, you can have different settings for SSB, AM and FM, and similar choices (including CW) on Rx. So I guess that is fairly good really, in a rather eccentric way.

When it comes to actually transmitting and receiving, it worked brilliantly. So far I have used it seriously on 40, 15, 12, 10, 6 and 4 metres and the ATU has dealt with everything I threw at it on HF. I tested it on all bands.

You change bands, as on the IC-7100, using the touch screen. This feels odd at first (I heard of someone sitting in front of it for hours trying to work out how to change band) but you soon get used to it. There is a button for all the amateur bands covered plus general coverage - except the 70MHz band (where available). I set up my main 4m frequencies in the memory, and there they are, accessed via the up and down buttons on the right. Once in place I can tune off the memory frequencies with the VFO. This is also the same system as used with the IC-7100. However, the 7100 did not have space for a button, whereas the 7300 does. Maybe those of us fortunate to have 4m will get a button in due course. It does not matter much as the memory system works fine.

There is a very useful "MPAD" memory pad button. I use it for storing working frequencies during contests. It is is a sort of notebook for recording frequencies you might sometime need again.

For operations, that ergonomic excellence we heard about above comes into its own. Not only can you see signals being received, you can set up your own outgoing signal using the screen.

Here you can see the station being received at the bottom of the waterfall, and at the top, my reply. This is JT65, so you can actually see the current tone being transmitted, and in darker blue, the peaks of the other tones in the signal. There is latency so that the blue shows the recent peaks. I can see just how wide the JT65 signal is as it is transmitted through the SSB "filter". You can (and I did) set up my microphone using the display on SSB. It can show both the transmitted signal and the audio graph itself. The permutations are considerable.

Here is a still image of me setting up the SSB audio taken as a screen shot onto the SD card (see more details of screen shot in the text further down):-

So, armed with a well set up tx signal how does the receiver rate? Excellent.

Listening to SDRs can be a bit strange at first. You miss the familiar crystal filtered sound you have been used to for years (decades?). What replaces it is a rounder, smoother, sound which works remarkably well in low signal situations. During a contest I had the full outboard preamplification on and I was struggling to hear a dx station. I turned off the preamps and used the 7300 barefoot. Although the levels fell, the voice was understandable well into the background. I sat and listened for several minutes at a level which would never have been possible on a superhet rig. More proof that signal/noise is the key figure, but that signal would have sunk into the noise on any other rig.

Do you know what the IC-7300 sound reminded me of? This is silly. An RCA AR-88. A World War 2 valve era superhet rx with a crystal filter in the 455kHz IF. The AR-88 was remarkably quiet to listen on, which might be because it was deaf. But the 7300 is genuinely quiet. I might even listen to morse on this. Frankly, it is a pleasure to receive on either of them.

Now I am not going to suggest that the IC-7300 is the rig to end all rigs. I feel pretty sure that Icom have kept quite a bit of performance up their sleeve for the rig that comes next. Even better receiver performance is probably in the wings. However, for a introductory rig from the big manufacturers this is hard to beat when everything else they make is "old technology".

We have been spoiled for a time with digital signal processing. First a bolt on at audio level, then an addition at the IF, this has gradually weaned us off relying on crystal filters and onto the idea that we can use processing rather than radio frequencies to do our filtering. With the IC-7300 they go the whole hog. Basically, there is no superhetrodyne mixing and no crystal filtering in the conventional sense. Direct sampling of the RF avoids the need for all that. The firmware and software have to be good, and the processor too. At least the firmware can be updated via the USB socket. The thing is, it all does seem to be good.

Output power seems fine and up to specification. I checked it into a dummy load on several meters and it is around 100W on all lower bands and just over 50W on 4m. That is at full carrier, on SSB it seems to perform as expected. Average SSB power measured on a general purpose meter is about 50W, so peak is going to be around 100W. It is in line with modern rigs in that, thanks to digital processing, there are a lot fewer distortion products in the final audio than we used to get with analogue processors. Sometimes that makes the average power appear lower. Nevertheless, you still need to produce 100W on the peaks and the 7300 does seem to do that. I will dig out my peak reading meter at some stage and check, but it looks fine. Let me just say that the IC-7100 started off clearly not producing what you would expect on SSB, whereas the IC-7300 shows no signs of that problem.

Likewise frequency stability. Without all those many mixers and oscillators it should potentially be more stable and accurate. That does seem to be the case. Once again I will check it with my GPS frequency standard, but there hardly seems much point. It passes the WSPR stability test, which is as good as you need for almost all purposes. The beacons appear where they should and stay there.

It gets warm but not hot. The fan is in the background. As I have it in a shelving unit I have a 10cm fan on the back of the unit which runs with the tx on 4 metres (which is the band I mostly use it for). That seems like a useful precaution.

The headphone jack is on the front and works fine.

There is a button on the front for VOX which also works fine.

The ATU works quickly and matched well. Everything seems to fall to hand easily during QSOs, except the buttons under the pass band filter knob which I cannot see from where I sit.

The speech compressor looks good on the display and received praise during operation. I mostly leave it off, as I do with all rigs. Again, the IC-7100 issues have been left behind as the architecture is entirely different.

I have fitted an SD card. Using it is much better than the IC-7100 thanks to better layout of the screen options. I have recorded a couple of CQ calls and I use those regularly. You can choose from eight you recorded on the rig. See here for keypad control of these http://gm4fvm.blogspot.co.uk/2016/07/experimental-icom-ic-7300-keypad.html. (EDIT - apparently you can now buy a keypad from SOTA Beams for £65.00 - mine cost about £10.00). The SD card can also be used to record QSOs, which I have also done. It can also capture screen shots. Here is a screen shot of me calling CQ taken on the rig with the push of a button:-
Operating is a real joy. That very quiet receiver and also the adjustable everything (pretty well) on both the tx and rx sides make it a pleasure to use. Are the buttons a bit small for use during a busy contest? Maybe just a bit. They are almost flat to the surround and need to be press in below the surface. But for normal use they are fine.

3) Data modes and computer operation.
Once connected by a USB lead, the rig sets up a virtual audio port and a COM port on your PC. I already had drivers loaded for the IC-7100 so there were none to load. If this is your first installation it is probably best to check to see if there are drivers to install first. The data disc supplied with the rig should have them, or the Icom website, where you will also find any firmware updates.

Data modes are easy, generally you just point your software towards the virtual ports.

So I have all the data modes I need onboard. How does it work in data modes? Great. You just select "Data" on the mode screen after USB - it shows USB-D. You can watch your signal going out on the monitor screen.

Computer operation seems fairly straightforward as far as I can see. Thanks to Scott, MM3LSO, I have discovered the Icom RS-BA1 remote control software. This is easy to install, but you have to pay for it. Here it is showing the Angus 4m beacon (GB3ANG) which, as you can see, uses FSK to key its carrier:-
To use the software you have to go into settings and select "CONNECTORS", "CI-V" and then "Unlink from Remote". To use other control software like WSJT-X or HRD you have to reverse this and select "Link to Remote". That would be fine it you only use the remote software and I guess most of you will only do that. But for me, who switches back and forth between packages, this is a wee bit of a pain in the proverbial. Link and unlink from remote have been much used by me.

The remote software allows you full control of the rig from your computer (or any computer on your network or the internet, depending on how it is configured). Which allows me to sit in the living room and watch "Midsummer Murders" while watching the waterfall at the same time.

For the shack computer, it is a nice idea to have a big screen with the waterfall majestically descending. By default if you use the RS-BA1 software you use the PC microphone. Apparently there is some way to use the RS-BA1 software to display the interface, and the waterfall, while using the rig microphone on transmit. I have not found out how to use it that way, but to be honest I have not looked very hard.

RS-BA-1 looks nice, but I doubt if I will use it beyond curiosity while sitting in front of the telly. The idea of controlling the rig from the computer as I did with the Flex seemed like a good idea before the rig arrived, but now that I find it so easy to drive using the touch screen I am not using RS-BA1 at all. Others may feel differently, especially if they do not use data modes in the way that I do, which involves all sorts of switching back and forth.

The ability to input and output your data modes via the USB lead is very helpful and it cuts out the need for a data interface. Remote operation is not for everyone. For me, my rig stays firmly in the shack beside me, but it will be a bit of fun from time to time to work it remotely from the living room.

4) Some sort of conclusion
I cannot really find anything major wrong with it.

The real breakthrough for me is the touch screen. Being able to watch a large slice of the band and then select any signal by touching the screen to change the frequency is very helpful. But the Flex 1500 had that on the computer screen (but you had to use a mouse). It kicks the Flex into the dust. It can work stand alone with no PC, it has an ATU, it has a touch screen, it has 100W ... OK it is a bit less than twice the price, but it is vastly more practical than the Flex for what I do. The IC-7100 has a touch screen, 2m and 70cms, which is all good, but it is not an SDR and does not have an ATU, spectrum display, etc. The IC-7100 has its place (it works very well in almost all respects), but it is a step behind the 7300.

Looking at the FT-450, I see a rig that is already showing its age. Very presentable and usable, its old screen and crystal filters give it an almost antique feel. It is great value for money. But it does not feel like the sort of rig which could cut it in the thick of a contest. It is fine for what I use it for, and that is good enough for me.

I had some reservations about a touch screen when I got the IC-7100. Now, two years down the line I think nothing of using the touch screen. Some poor souls got a faulty 7100 screen and the rig was dead on arrival. Stuff happens. But if the screen was to fail how easy or expensive would it be to fix? I do not know, but I do know that ordinary buttons and knobs also fail, and we manage.

Lets get some of this into perspective. The IC-7300 is my third SDR. It shares many things with the others, such as the spectrum display and the ability to customise almost everything. But the IC-7300 is really groundbreaking in making these things available at a price in line with other rigs, inside a rig box,with a touch screen, and capable of working stand alone.

According to the Icom blurb, the 7300 apparently has a 124MHz ADC, which in theory gives it a top frequency at full resolution of about 62MHz. It might not be just perfect on 70MHz, but it cannot be expected to function on 144MHz. So that is it for now. No doubt later we will have something with a faster converter and therefore a higher top frequency. It would also be nice to have something like a HDMI socket to allow the small screen to be shown on a larger touch screen. Again, no doubt that will come eventually too. When all this pans out, I might slide the 7300 down the scale and put it where the FT-450 is now. I suspect it will be very good there. I think it is another "keeper".

5) Finally
I like it a lot and it works very well.

And I am hard to please.

73

Jim
GM4FVM

Tuesday 19 April 2016

VHF enlivened by early Sporadic E.

Tah Dah!

It is official:-

Mon 1446 UTC: 70 MHz E-skip Alert - 4 m Band open from SP8QEJ to GM4FVM on 70200.0 kHz

A nice e-mail to receive on 18 April.

There has been a sudden blast of Es. 6m was humming on 17 and 18 April, with lines showing contacts all over the European map. I was caught without a 6m antenna up, after I dropped it a few weeks ago. However, I had a fair idea that such strong Es might reach 4m, even if only briefly. And for once I was right.

I have been very busy trying to get the antennas ready for the new season. Which season? Well, Es, meteor scatter ... anything really. I know the season has ended as the last 6 weeks have been terrible. So something better must come along eventually. All that statistics training must have been some use. I know that if things are regularly bad they must be about to be regularly good. Technically it is called "reversion to the mean", or just the song "The Sun will come up tomorrow". Or it doesn't improve, as the case may be.

10m has been so bad that even just the past few days has counted as a real opening. Great to see Europe on the waterfall, plus a bit of DX thanks to one big sunspot. And that sunspot even fired off a flare, but not in our direction it would seem.

I was busy putting up the best multi-band antenna I could find, given that the quad band one I bought is not really working for me. After a report from Duncan, MM0GZZ, I invested in a Moonraker tri-band 6m/2m/70cms vertical. I am not keen on Moonraker in general, though this is silly as they seem to draw their antennas from various sources and therefore they are not all the same. The key factor was that it was £90, whereas the equivalent Diamond was £180. Then the Diamond went on sale at £90, and strangely the Moonraker fell to £50. At £50 I thought it was worth the risk.

Years ago I had the Diamond, and I expected the Moonraker to feature the same construction. However, it has a single fibreglass-encased set of radiators so there is no joint, and it is supplied ready tuned. There is no adjustment even if you wanted to tune it (but I do have my trusty hacksaw). So  I put it up and it worked. Let us see how well it does, but first reports are very good.

Here it is on the left. The antenna on the right is the 4m 5/8ths.
I think it could go up another metre or so, but I will need to extend the guys and so forth so that will have to wait.

It did not quite work straight from the box as I managed to fit the PL-259 plug wrongly at the shack end. Eh? Well I have become a bit of a fan of compression type plugs, but this one went wrong. I put it together and I now know that the ring which fits under the outer plastic insulation had pushed the braid back along the central insulator instead of fitting round it. That might not have mattered if I had not taken it apart for some reason and then on refitting it the ring failed to make contact with the displaced braid. Strange. Anyway, after a bit of a panic I worked out what was happening and remade the plug again. Something to bear in mind when I use them in future.

I was in a bit of a dilemma. Should I be outside during a 6m lift, putting up a 6m antenna, or should I be hoping for a 4m opening, in which case I would be better inside at the rig? I split the difference and kept rushing in to see if anything had appeared on 4m and sure enough it did.
SP8QEJ seems to be posing in front of the Polish secret police during night operations.

I worked him on the IC-7300 (still working on the review). That should not matter much as you cannot buy one even if you wanted to. They are very scarce just now.

Two days of a lift, and all I have to show for it is one contact? Yep, but a 4m contact is worth a lot of 6m ones. Anyway, I had no 6m antenna until late yesterday and it is just a vertical. So I am happy with that.

Since the 6m HB9CV fell (or I dropped it, or whatever you could call that) I have been thinking of ways to put it back up. I have now worked out a way of putting it back on the wall brackets currently holding up the 4m vertical. I would never put two antennas and a heavy rotator back up there, so it will be just the HB9CV and a TV rotator. Arrgghh. TV rotators. They are rubbish. They are poorly made and they do not last long. A couple of years and they die - sometimes less. But I am not risking anything heavy falling again, so whatever goes up there has to be light enough for me to install and remove safely.

Not only are TV rotators dreadful, they are not even available. I tried all over Europe and they have disappeared. A far cry from the Conrad at £50 of a few years ago. So I have imported one from USA. And it was cheaper than the last European price, even after I paid the carriage and the import taxes (well, just 20% VAT really). All I need to do is provide a 240V in/ 18V 1 Amp out AC power supply. The control box is adjustable between 50hz and 60hz mains supply. Even more amazing, the imported one has a snazzy digital control box and remote control. Not like the clunky buzz boxes of old. The only snag right now is that the digital readout in degrees is pretty inaccurate, but I will take the covers off and have a dig inside. Even if I do not change that side of things, it is fine for my purposes. The HB9CV does not need pin-point accuracy. But fundamentally it is still a lousy TV rotator with plastic gears and poor weatherproofing.

So more work done. More to do. But a little burst of Es was just what I needed to perk me up.

I have just spent a while calling CQ on 2m and 4m looking for meteor scatter contacts. Nothing doing. Come on Lyrids and Eta Aquarids. Where are you?

73

Jim

Thursday 14 April 2016

A different view of aurora.

I have been finding out more about the IC-7300, but propagation conditions continue to infuriate me. This time of year is always frustrating for VHF-types, as meteor showers and sporadic E improve the situation  by the end of April, which makes these few weeks seem unbearable.

I have been so bored I have been receiving pictures from the International Space Station as it passes over.




Yawn.

But the neighbours like them. Shows them what all those awful antennas and masts are for.

There was a small aurora yesterday and today (13-14 April 2016). Nothing worked from here but I thought you might like to see the GB3NGI 2m beacon as seen from here via the auroral curtain.

Usually I have to beam 260 degrees (almost West) to find the beacon, because that is where Northern Ireland is from here, but during an aurora I beam at 30 degrees (just East of North) and the beacon signal, though loud, has no tone and sounds raspy.

Here is an unusual view of the SpecJT graph of the beacon's signals via aurora:-
You can see a wide fuzzy line. Starting from the bottom left, that is a carrier, though as you can see it is very wide. The point at which the signal starts sending an ID in JT65B mode is where it starts stepping around. It then moves over to the upper trace and you can see the data ending and then after some carrier you can see the callsign being sent in morse. For comparison here it is direct and not via the aurora:-
You can see the carrier clearly now, and even the morse. The JT65 can be clearly made out. You can see the signal strength marked by the green line and it is spiralling about due to tropospheric variations and aircraft scatter.

The wide distorted signals on aurora are very difficult to copy. That is why CW is so good, as the presence or absence of a signal is easier to observe. Despite that, I do make SSB contacts, but data, as you can see, is impossible.

Those images were taken with the FSK mode waterfall, which scrolls left to right. I switched to the JT65 waterfall which goes downwards.

Here are two more images, this time the top one shows the direct path, and the bottom one shows the auroral path. (To keep you on your toes I am swapping them round from the images above). I will not bother showing the decode results on the auroral one, because as you can imagine, there was nothing to decode. The multiple traces on the direct carrier (higher waterfall) are due to aircraft reflections - though the signal decoded perfectly. The wide splodge on aurora waterfall (lower) has no chance of decoding.
Sometimes I wonder why I struggle with aurora, as the signals are sometimes almost impossible to copy. Well, it is a remarkable natural event, and in fact I feel privileged to hear it. I do not really mind when I do not make a contact, just being there to witness it is enough for me.


Believe me, if it looks odd, it sounds WEIRD.


73

Jim
GM4FVM