Friday, 19 February 2021

Multiple instances of WSJT-X - using more than one radio, or two data streams on the IC-9700

Imagine the situation. You have just bought a shiny new radio. You want to receive and transmit data on it, but you still have your old one hooked up. You could be, say, monitoring HF and VHF at the same time, or indeed any combination of bands between the two radios. You might want to transmit on more than one band at once, or monitor more than one mode on the same band.

Or maybe you just want to leave both radios hooked up but sometimes use one or the other. You cannot be bothered to keep switching about in the WSJT-X settings. Well, here is the answer. You just click which ever one you want and up it comes. Close it and open the other one to change rig. Easy.

You can see the result here below. From left to right are the readouts from my IC-7300 on 4m, IC-7100 on 70cms, and IC-9700 on 2m. There is in fact a reason why they are arranged in that order - the radios have to be in the same order on the bench below for space reasons - and it works for me. I have a separate display screen for this display. The object of the exercise is so that I can follow propagation up and down the bands, which is what I watch very carefully.

WSJT-X display at GM4FVM showing three instances running at the same time


 

As usual, click on the images to enlarge if you need to.

The WSJT-X home page leads you to a guide to WSJT-X which explains that this is easy to set up but then seems to be a bit vague about how to do it. There is a link to the WSJT-X home page on the side bar to this blog and you can go there and see if it makes sense to you.

For me, I use a slightly different system for setting it up, but I achieve the same result in the end. I have recently been using both data channels of audio from the IC-9700. In effect this creates a new radio to monitor - the "IC-9700 Sub band" radio.

Up to now I have been using MSHV to monitor the IC-9700 Sub band. This works fine but MSHV does not cover the JT4G mode used by the GB3NGI beacon so I have to switch to monitoring 23cms on the Main band and then 2m is on the Sub band and I cannot transmit on that so I have to keep switching ... ...  look, never mind about all that. Let us just say that I am about to set up another instance of WSJT-X and I thought I should show you how I did it.

Please note that what I am describing is for Windows PCs only. This is because I know very little about other operating systems (what makes you think that you know much about Windows either, Jim?). I suspect that the same thing is possible in other operating systems, it is just that I have never tried it. Someone familiar with other OS arrangements can probably translate it to them fairly easily.

It is simple enough. First you create a new desktop shortcut to point you to a new rig name in WSJT-X. Second you need to create that new rig name in WSJT, which is fiddly. With my method you do them in that order. After that you can use the desktop shortcut to open the new instance and set it up as usual in WSJT-X. You can run either instance separately or both together. This new one will make four for me.

You are probably best to rename your old rig too just to tell the difference between them but strictly speaking you do not need to do this as a third stage.

The FVM method

OK, my first step was that I found my desktop icon for WSJT-X, right clicked and click "Copy". This gives you a copy of a link you are going to use to open the second (or later) instance of WSJT-X.

You now need to paste the second link to the desktop so that you can decide which one (or both) to open at any time. It should be obvious already that these icons are going to need different names so that you can tell them apart and know which one to open.

When it comes to pasting the link, find a place on the desktop (you can move it later) and paste it there. It is important to paste it as "PASTE SHORTCUT" and not just paste. If you click just paste it will just paste the image and you will spend a lot of time clicking on nothing. I Know, I Was That Solider.

OK, right click on the desktop and click "Paste shortcut". The icon will appear with a title attached which will be something like WSJT-X (2) with a version number. You need to right click on this, click "Rename" and give it a title something like "WSJT-X Banjo 3000" (this would mean most if your new rig is indeed a Banjo 3000, otherwise use the name of the rig). Then you might want to do the same with your first version of the shortcut and rename that "WSJT-X Old Rig" or some suitable title like "WSJT-X Yaesu FT-897".

You do not really need to retitle them if you can cope with WSJT-X and WSJT-X (2) for titles but I got totally lost with that. When I had two IC-7100s I called one A and one B but it was still mightily confusing. Perhaps it is best to use easily recognisable titles.

Probably best to give them meaningful names

OK, you have two shortcuts with different titles but you cannot open these together because they both point to the same "rig name" in WSJT. Confusingly WSJT needs a different rig name too and it gets very stroppy if you try to open the same name twice.

This is a simple idea - you just add some text into the "Target" box of the shortcut. You need exactly the correct text.

I went to the new shortcut I had pasted and right clicked to show the "Properties" screen.

Your addresses in "Target" and "Start In" will be different from mine for reasons of my stupidity in the past, but ignore that. All you need to do is add on to the end of the "Target" line a suitable text element. The snag is that the text has to be pretty specific.

After the .exe ending you add a space then --rig-name=Banjo3000. Right so that is-

[SPACE] [DASH] [DASH]rig[DASH]name[EQUALS]

followed by your rig name.

In my case  --rig-name=IC9700SubBand

Don't forget the starting space, the dashes are the middle of the line ones, not "underscore". You rig name can be anything but maybe it is a good idea to make it the same as the name you gave the shortcut. Less chance of confusion if you call it the Banjo 3000 all the way through. Or Kenwood TS520 or whatever. For the name I do not use spaces, strokes, dashes or odd symbols, just letters. There are enough dashes in the target line already.

Then click "Apply".

You might, as I say, change the name of your original rig in the target line of its shortcut too. You do not really need to so long as you remember that "the rig with no name" in WSJT-X is the first rig. 

Basically that is it.

I have no room for another instance of WSJT-X on the left hand display along with the other three, so it has gone on the right hand display which I use for PSK-Reporter. As I test I used the 2m beacon to check everything out.

IC-9700 Sub band being decoded on the new instance of WSJT-X

 Normally I use it for monitoring 1296 MHz so it does not see much decoding action. 

You can move the WSJT-X panels and wide graph about by clicking on the top bar, keeping the mouse button pressed and dragging them about. You could put two beside each other. Within limits you can resize them and also juggle about the graph scales to make it all fit. You might want to put the two of them beside each other, or whatever you choose.

You are now free to choose between which instance of WSJT you want to open or open them both together. Or in my case, four together (but I am a nerd). I have put some stuff about PC processing capacity while running WSJT-X at the bottom of this posting. Unless you have more, fairly ambitious, plans it is unlikely you will run out of computer power just by adding a second instance.

As I said, you can move the WSJT-X panels anywhere on your display screen. If your PC screen is already cluttered you might want to add another display screen. This is a good use of that old screen you put in the attic - it can do the mundane email stuff and let your fancy new screen show WSJT-X off to maximum advantage. If you have multiple display screens you can do bizarre things, as I have done. You will need a suitable display board to run more than one screen (though many laptops and fairly basic PCs can run two). But if you are happy with both instance on your main display screen you do not need to bother about any of that.

You might need to juggle connection standards for multiple screens - I am using one each of SVGA, DV-I and HDMI plugs. Adapters and gizmos to help are available and you can now sometimes use advanced USB sockets for even more display screens.

If all you are doing is switching between two rigs then this will cause no PC processing problems at all. Two instances running FT8 together should be fine too. Once you get beyond two instances it might become a bit more difficult in terms of processing power. This might be particularly true if running multiple versions of, say, MSK144, which uses a lot of processing power. If so, see below.

Over to you now that you have set up two instances of WSJT-X.

Icom IC-9700 [EDITED 24/2/21 re sound card setup]

I will carry on and explain how I set up the second instance of WSJT-X to decode the Sub-band on the IC-9700.

First you need to have your PC sound card set up to receive two channel ("stereo") audio. Windows sets it up for mono by default. For this see my earlier posting here.

 Or you can look up the site which set me off on this path (which is better written than mine)

 https://klop.solutions/stereo-audio-from-ic-9700/

Note that on the Klop site he used a lower audio bit rate which might save you a bit of procesing power, but I doubt that will matter much.

Anyway, assuming that you PC is ready. let us go back to the tale of the WSJT-X setup.

As the Sub band has no CAT control and it is not possible to transmit from it, all I am doing is a receiving set-up.

Lack of CAT control means that in "Radio" settings I set Rig to "None", port to "USB" and PTT to "VOX"

Radio settings for the IC-9700 Sub band.
 

In "Audio" I set Input to the IC-9700 soundcard and right hand channel. Output is irrelevant as there is no transmit, but I set it to the PC speakers to remind me just in case I stuff it up someday and try to transmit.

Audio settings for Sub band on the IC-9700.
 

If I get time I will post something about what you can do with the IC-9700 in terms of cross and split band operation now that you have set up more than one instance of WSJT-X.

PC processing power issues.

It is possible that you could outrun your computer processing power if it is already running short. Running multiple instances puts more strain on your computer, and a fair bit extra if you use multiple displays. Most modern computers can handle it. 

With three display screens and four instances of WSJT-X this is an issue for me, but would not be for most operators. Because I specifically monitor multiple bands I have higher than normal usage.

I used to have problems with this but not after upgrading to a fairly low-spec second hand gaming computer.

With my setup - Intel Core i5-7400, 3GHz, and 16GB of ram, running W10 20H2, four instances of JT65 involves my machine using 35% of CPU and 38% of memory. Four instances of MSK raises this to up to 50 to 60% of CPU - but I would never expect to find myself running 4 instances of MSK. Note that this is only WSJT processing load, in my case the displays are run from a separate board.

I think that multiple instances are more likely to create issues with display processing than running WSJT. After problems in the past (back in the days of Pentiums, but an elephant never forgets) I have always fitted a higher spec display board to handle all three displays.

For this reason if you do decide to go for multiple display screens it might be worth considering a gaming-type display board with lots of on-board processing capacity to handle the displays (mine use 1.7Gb on a NVIDIA GTX1050 display board, but use virtually none of the main processor capacity as a result). But for most situations it will all work fine.

Warning

Running multiple instances of WSJT is a simple step to take for the many individuals who use two rigs, say for HF and VHF. The danger is that you get carried away. You start running many instances, you need multiple display screens to cope with all this and watching dx Maps and PSK Reporter at the same time, you need a bigger computer, you need more antennas, more masts, more rotators, you need a bigger shack, you need another job to pay for all this, ARRGGGHHH. 

More of my life story later. 

73

Jim

GM4FVM

P.S. Sorry, like every posting there is bound to be a typo in there somewhere. If this is stopping you getting WSJT to work I will try to update any flaws if I find them. Good luck and enjoy it. Jim

Thursday, 14 January 2021

Nice Winter Sporadic E opening

My mood remains dark. Amateur radio is not my best friend right now.

In a glum e-mail to a sympathetic amateur recently I explained that I have a need to go QRT for a time to recharge my batteries. However, in the same e-mail I confessed that if there was a warning of a good opening I would be back.

There certainly seems to be a tendency for old men to become more grumpy as time goes on. I try to resist this ever-encroaching crabbed-ness. These grumpy hams tend to believe that they have all the answers - that they have nothing to learn and lots to ramble on about. They have each become, in the words of Granny Reavey, "an old stumb". I speak in particular of those who issue pointless propagation predictions advising us to look out for "two or three weeks" for an opening due to the way the wind is blowing. I kid you not.

OK, so I am like that too. However, I still think that I have a lot to learn in this hobby. The old "rules" (were they ever rules?) are open to revision. This is particularly so when considering propagation where we are always learning more. 

Amateur radio is a scientific hobby. The scientific approach means we should establish theories, but these are always open to revision as we learn more.

The conventional wisdom is that a phenomenon exists called "Christmas Es", a form of sporadic E which happens at the Christmas season. This idea is clearly nonsense as the ionosphere does not recognise the calendar. Could it be that many amateurs take Christmas off work and spend their time avoiding their families by coming onto the radio - and thus noticing a phenomenon which has got nothing to do with Christmas?

Anyway "Winter Es" seems like a more sensible description and as I have rambled on for several years on this blog it can occur for several weeks on either side of the Winter Solstice. Also, despite endless waffling from these people about "stratospheric air currents" (the latest wheeze to cover the fact that Jet Streams are not responsible), the best way I have found to predict these events is to watch the reported levels of charged particles coming from the Sun as indicated by the magnetometers. Especially useful for this is the Norwegian Line list for which there is a link on the right panel of this blog.

There was a really nice Winter Es event here on 12 January 2021, with a smaller opening the next day. I was ready to emerge from my hibernation because there was an auroral opening the evening before. The aurora is a sign that a high energy particle flow is streaming past the Earth. Not that every flow from the Sun will "trigger" and Es opening, but if we are in the period when there might be one the flow will push it over the threshold.

So was I more or less ready, given that it was within the Winter Es period and I had some warning?

Well, surprisingly so. I have also been ignoring all sorts of wisdom about sunspot cycles. Seeing the latest figures I had added another attic dipole to my existing on 10m one. The two dipoles are at right angles controlled by the antenna switch on the second hand MFJ-929 ATU I acquired for almost no money some time ago.

On the new 28MHz dipole I managed to work CA3SOC, a distance of 11852 Km, on 29 December 2020. I was fairly happy with this as it was done on 25 watts and an indoor antenna. Sufficiently emboldened I then put up my Sirio Gainmaster HW vertical dipole. I reckoned that there might not be much going on yet, but I should be ready for it when it does happen. This is a bit of a lash-up and it is fed with less than perfect coax. It was quickly clear to me that I can do better on 10m. I am not getting out well as the ATU is doing a lot of work. Eventually I hope to replace this vertical with the full size Gainmaster which is also still in the garage.

Anyway, come the opening on 12 January I was able to use 10m as a guide to what was happening on 6m. This is my preferred method of working Sporadic E. I watch the bands from the bottom up, starting with 10m, then point my antenna on 6m in the direction I can see from the lower band is likely to be best. Given that the 6m opening was at times divided between North East and South this was very useful.

I use the same tactics on 6m and 4m, 4m and 2m, and then for tropo openings 2m, 70cms and 23cms. I know this method runs contrary to the way most amateurs work. I am not most amateurs. From what I can see most amateurs invest a large sum in a vastly expensive radio and then sit on one band. I am not sure whether they care what is happening on the other bands. I prefer to divide my money between several rigs none of which is perfect, but the result lets me hop about chasing DX.

Anyway, enough of all that. 

The result was 108 QSOs, reaching 74 squares and 22 DXCC on all bands. Nearly all of these QSOs were on 12 January, while 13 January produced 9 QSOs and 6 DXCC.

Looking at 6m, which is where my main interest is:-

50MHz FT8 contacts at GM4FVM 12 and 13 January 2021
This was 46 QSOs, 35 squares and 17 countries on 6m, best DX IT9RZR in JN76 2474 km.

For me this opening shows the joy of the Winter Es. OK, the aurora gave me some warning but the surprise was still there. My aurora warning software went off twice the evening before, but the QSOs recorded were all to the North East of me. Nevertheless, it alerted me to be ready to try the following day. What I did not expect was the size and duration of the opening.

It is not really possible to predict Es openings accurately, given the current state of knowledge. Even if we could, it would probably be impossible to say if would affect any particular station. Most openings to the West and North come to nothing for me. That makes the ones that do happen all the more interesting for me. I remember the feeling when I fall outside the zone covered, so I make hay when I am inside the zone.

As for using space weather to predict Es openings on a general basis - well I find it works during periods when we might expect an opening anyway. But during the "off season", say in February or October, well, then we are very unlikely to get an Es opening which we could predict. 

Increased solar wind might kick an incipient opening into action.

I used 10m to guide my 6m activity. Even with an antenna which was not radiating very well I had 57 QSOs, reaching 43 squares and 15 countries, with best DX being UA6HJT in LN14LC at 3405 km.

Sirio Gainmaster HW showing the lovely January weather at GM4FVM
The real purpose of the Gainmaster is for F-layer DX. That QSO to Chile has raised my expectations.

As I write this on 14 January I have just worked another 11 stations on 6m in 7 different DXCC. I had to take a look today as there was a large disturbance in the Norwegian Line of magnetometers between 20:00 and 23:30 last evening. Co-incidence? Well, I am not about to turn into a grumpy old fart droning on about this. I encourage people to make up their own mind.

Right. I am off to my darkened room to listen to the cricket on the radio. And I have to watch Junior Bake Off too. VHF ham radio? Really? At this time of year? Surely not, as that would break all the rules.

 73

Jim

Friday, 25 December 2020

Happy Christmas

 

Best wishes of the season from GM4FVM

Sunrise at GM4FVM on 25 December 2020
 

Above is a photo this morning of the sunrise here, with the antennas firmly lowered. 

I could have brightened the foreground in Photoshop, but the murky appearance just represents my mood perfectly.

Perhaps part of that glow in the sky is the blazing masthead preamps of a fellow GM. You have my sympathies Tom, I have never seen a mast-top fire before !!!!

I have not reported much lately because I have not been doing much on the radio. I have been concentrating on many other things.

Still, everything is looking up! We have passed out the period of sub-7hour days, with the day length having risen to a giddy 7 hours and 1 second. VK heard on 10m, a small "Christmas Es" event on 6m and ... well nothing much to write about really.

I seem to have lost my way a bit with the radio. This is not a hobby that gives freely and consistently: for me there are times when the enthusiasm wanes. If I have learned anything over the years it is that the best plan is to let it go. Switch off and do something else for a while. It is a bad idea for me to keep thrashing on when there is nothing available to keep my interest up.

So, until the fog inside my head lifts (which might be this afternoon), all I have to say is Happy Christmas.

Plus, of course, have a great Hogmanay, and don't do anything I wouldn't do.

73

Jim

GM4FV

P.S. Is there anything worse than a bad deal? Yes, a dead band. 

P.P.S. For anyone reading this posting outside the UK, I will not try to explain the above. It is impossible to translate into the real world.

Monday, 30 November 2020

Sometimes it all goes wrong

 Argh! The last few weeks have seen all sorts of chaos here, but hopefully things are a bit simpler now.

At one stage I sat down here, exhausted and cold, and nothing worked. At that stage I just thought of giving up this hobby. Is it really worth all this self-created hassle just to prove that photons propagate?

Anyway, I did move along and get most of the issues fixed. They were, in no particular order:-

1) my computer needed to have Windows re-installed

2) EMC problems on 70cms mean a complete re-jig of the antennas

3) both my sequencers failed at the same time.

4) noise on my PC HDMI display lead was affecting several bands

Plus, my work website went down and I ended up changing the domain registration, which need not bother us here. It was, however, another layer of complexity which had to resolved quickly.

And I have to face it all without Katy, my loyal shack cat. After 18 years of enjoying the warmth of the radio room, she died recently. Sure she had a good innings, but I really miss her.

Katy in charge, back in 2007.
 

It should not be necessary to make a fresh installation of Windows these days, you are supposed to be able to repair it while leaving everything intact. That does not work when the fault is one which prevents the repair working, and it also stopped security updates and other useful things. So it had to be done.

I have now reverted to separate 2m and 70cm antennas, and these are on my CUG mast rather than the Tennamast where the dual bander was before. Before this could be done I had to recalibrate my Yaesu rotator and run a test to see if it is accurate enough for moonbounce work (it is, just). My old 4m/6m Vine antenna is now on the Tennamast. The new arrangement is better in various ways, and worse in some other ways. All the connections on all the leads coming into the shack had to be changed. We shall see if it fixes the EMC problems but it certainly seems to work fine for 2m and 70cms, so far.

Due to the sequencer problem I had to rely on the IC-9700 for 70cms instead of 2m, because it has a built in sequencer and DC supply for the preamp. So the IC-7100 and the IC-9700 had to be swapped until the sequencer could be fixed - which it now is - so then it all had to be reversed again.

The display noise thing is a big problem. I have a super-wide LG display which I had to throttle back to standard width which meant the screens did not fit properly any more. I had to move all the sceens to different displays. After a lot of work I have just now reached a reasonable solution thanks to a heavily screened HDMI cable.

Effect ... at one stage ... all the rigs were moved to different coax lines feeding different antennas and showing up on different screens. All the settings in WSJT-X had to be re-entered. All the backed up logs and copies of circuit diagrams and manuals had to be restored to previous places on the PC. Due to the sequencer failure, nothing worked on 70cms until it dawned on me to swap around the radios again, which was more work.

Moving the antennas was started lacking in any strategy. I kept doing things without realising the consequences, and then I had to redo them or change them.

I got the initial antenna swap done, involving taking down two antennas and replacing them with three others.

And then I discovered that in one case I had put the wrong antenna up (how do you do that?). 

And then a change of plan meant that one (that had been changed already) would have to be changed again. 

And then it was decided to swap two more between one mast and the other.

And then I discovered that I had put one of the elements in the wrong place. 

Repeatedly I had to leave the mayhem in the shack and go outside into the cold to work on cold metal tubes with frozen fingers. This was either because I had not been thinking any part of it through, or if I had I had not thought out the best way of resolving the plan as a whole.

GM4FVM in full winter gear (hoodie, Caravan Club fleece) re-orders antenna elements
 

So as I said, I sat here at one point, back in the shack, all alone, and wondered - is this hobby worth it? Have I relied too much on computers and gizmoidery and forgotten the basic joys of this thing we do. Is it not supposed to be fun rather than a to-do list as long as your arm?

Re-installing Windows from scratch causes mayhem if you use a lot of data modes, control your rotator from your PC, measure your power and SWR on your computer ...

The answer of course is not to do all those things. If I just had a radio plugged into a length of coax, as I had in 1974... 

On the other hand, sure I could turn my rotator by following moon charts, but I find it easier to aim it following the simple readout on WSJT-X. In fact, I just click a button marked "Tracking" and they both do the following themselves instructed by the rotator software, leaving me to think about more weighty matters.

Separate 2m and 70cms antennas have replaced the dual bander

I do it the way I do because that is the type of radio amateur I want to be. Sure, it means that sometimes I can be let down by the technology, but in my view fixing it allows me to learn how it works. And when it does work it is brilliant, in my rather skewed opinion.

On the up side were contacts with NC1I and DL7APV on 70cms EME, plus emails from both of them, which was nice. Also, the new arrangement, whilst it is worse for 4m and 6m, may allow for better antennas on 2m and 23cms in the future. I could not do that before due to space constraints.

I cannot deny though that this has left me drained. At least once I did think that I could just stop there and then, and take up quilting instead. But Swing Out Sister and George Gershwin combined to revive me.

73

Jim

GM4FVM

Friday, 6 November 2020

A bit more moonbounce, at last.

I am not a fan of high power. I do dabble with it, but I do not routinely run full legal power.

I can see, however, that in certain situations on VHF there is no alternative. In particular this applies to scatter modes of propagation, such as aurora, aircraft and meteor scatter and Earth-Moon-Earth (EME or "moonbounce" as I still keep calling it).

Recently I have been complaining that my maximum 70cms power output (65 watts) is a bit low for moonbounce. I am astounded, of course, to have worked anybody on 70cms moonbounce with that sort of power. When you add to that the path loss over 200dB, plus the vagiaries of the moon and the almost total lack of activity at 70cms, then it is surprising that I have a set of results to point to at all.

To make EME work you need to reach a budget of power and sensitivity which is pretty marginal at 65 watts. If, by the use of suitable equipment at each end you can reach the budget you can have a QSO. If you fall 1dB below it nothing happens at all. If you are on the margin, strange factors like Faraday Rotation, polarisation incompatibility or the Moon's variable distance can leave you with days of listening to white noise. On any one day you can look at the data and try to work out what budget of power you need, only to find that some obscure issue is preventing anything working. It helps to have some power in reserve.

But when it does work --- it is amazing. I have done very few things in amateur radio that have been more satisfying.

To reach your budget you can run a huge amount of power, have superb receivers or have massive antennas. Ideally all three. Or, in my case, none of these. To manage I use the same strategy as hundreds of other amateurs, I run a modest station and leave it to the big guns at the other end to provide the huge power level, the super-quiet receiver and the massive antenna. They don't mind, they love to work people with simple systems - it proves to them that their money was well spent.

Nevertheless, 65 watts did wear me down a bit. On a couple of occasions I heard stations who could not hear me. Mind you, they were using a kilowatt. The issue here comes down to having a balanced station. Do I transmit a signal comparable to my receive performance? Can I have a reasonable chance of reaching everyone I can hear (or hearing everyone who can hear me)? Of course, some stations will be out of balance too, but relying on them all to have super receivers does not seem too sensible. These people will have designed their station on the assumption that anyone calling them will have a reasonable set-up (whatever that is).

I have had a great time on 65watts. I would not wish to put anyone off from trying that sort of power level and you can work several stations using that approach. But I have bought a new linear. With a lot of inner doubts, I moved on and bought a Tajfun 1000 2m and 70cms amplifier. I had doubts because this has cost me more than any item I have ever bought for amateur radio. 50% more than I have ever spent before. 

It is broadly the same price as the IC-9700 (which I didn't buy, but would otherwise have been my most expensive item). Ouch. I will say more about it once I have put it fully to the test. Let me say that it claims to be able to run about 300W of data on either 2m or 70cms, though on 2m you do not have a low pass filter - luckily I already have a 2m bandpass filter.

The reason why I went for a 2m and 70cms amplifier was that, for some reason, I do not trust my 2m Gemini amplifier. Look back in the blog if you want to know why. I now have a hefty backup.

Tajfun 1000 2m and 70cm linear amplifier
 

I will have a better photo and more explanation about the Tajfun later. Early signs were that it is very happy running the 200W I expect to run. 300W on JT65 looks to be about the limit, which is exactly what it claims to be able to do.

So my 65W was about 12dB below those superstations running 1kW. 200W would raise me to -7dB, an increase of 5dB. In many cases that could be enough to make me heard - frankly even 1dB can be enough but you just never know with all the variables. If it was borderline I can now even muster another 100W which would add another 1.6dB.

Only time will tell if adding 5dB by running 200W will make much difference. This was a big expense and I am selling off one or two nice things to be able to afford it.

In normal operation on tropo contacts I doubt if 200W is really necessary. Where it may help is when I need to attract the attention of a station who is beaming away from me. It should help with marginal aircraft scatter contacts too.

What I am trying to do here is to bring my power more into balance with my receiver. I do not think that I need to go beyond 200W to do that on any band.

So I went on near moonrise and moonset to see what I could hear. 

Nothing. 

I spent a very frustrating week thinking that I had lost my touch. I tinkered with the settings on WSJT-X, I footered with coax, I meddled with the sequencer, but of course nothing changed. A linear is no use if you cannot hear people. I thought I had wasted my money.

Moonbounce is very variable in the sense that you see crowd behaviour. Stations flock to it when conditions are right, when the moon is nearest, and at weekends. Of course, I was trying at the wrong time.

On 4 November I looked on 70cms at moonrise, nothing, then watched the highlights of the previous day's Vuelta cycle race from Spain on the television. Then once that was over I checked again, still nothing. The only small chink was that I could hear Anatoly RK3FG on 2m. I did not call him because I had already worked him, and anyway it was 70cms I was interested in. That was the first EME station I had heard in weeks.

After watching "The Great British Bake Off" (isn't that EXCITING??) I wandered back to the shack intending to shut things down. Anatoly was still coming in on 2m, 2 hours after I first heard him, during which time the moon elevation had gone from 1.5 degrees to 15 degrees. Not likely to be much doing now as 15 degrees is surely far too high for me to reach with an antenna fixed on the horizon. It would need an elevating antenna to do that. Or would it?

Even more suprising was to hear Dima, UA3PTW, on 70cms. I immediately called him and we worked easily. So the linear works. Perhaps my money is not wasted. A new country on 70cms (Russia), and a new square of course, plus a new "unique". Moonbouncers claim uniques they work a new station. I had worked Dima before but on 2m, not on 70cms. Very nice.

It did not quite go according to plan because Andrew, G0JCC, was having a conversation I had not noticed on the N0UK moonbounce bulletin board with Dima. Basically Dima was encouraging Andrew to give him a call, during which I had waded in with my big muddy tackety boots on and called Dima. Ooops. Apologies to Andrew. Andrew runs a comparable station to me but has better antennas - which is perhaps a better way of achieving the same aim of putting a bigger signal on the moon.

So when I popped up on the board to apologise to Andrew I attracted the attention of Anatoly who asked for a contact. I do not know if he knew I was on 70cms, but I thought I should make the best of it and call him on 2m. That contact was also completed straight away with no problems.

 

144 (red) and 432MHz (blue) contacts at GM4FVM 4 November 2020

So for that day, 4 QSOs, 3 squares and 2 DXCC. Best DX, UA3PTW in KO93 at 2553km. Not bad for 70cms, when you consider that the round distance via the moon was a bit over 800000km, not actually the apparent 2553km. 

All this proves that the new linear works. I could hear both stations on the loudspeaker. I must remember that I can work people at 15 degrees of moon elevation, even with horizonally fixed antennas. It is worth checking in the shack during breaks between TV programmes, even if all you expected to do was to turn everything off. Dima came straight back to me after my first call, he was not expecting it, so I am being heard. G0JCC worked Dima too, so I am on a pretty good level of competence if I can keep up with Andrew (this is the first time I had such a direct comparison with another station).

This much I have learned.

Next two days of listening at moonrise and moonset produced ... nothing.

I am worried about that, which shows that I may have learned nothing.

But, hey, the propagation to the Moon is always better at the weekend. And this is Friday!

73

Jim

GM4FVM


Friday, 9 October 2020

New extension cable for my Tennamast.

WARNING: If you do this please observe safety precautions. Follow the Tennamast instructions and contact them if in doubt. What follows is what I did freestyle myself. The Tennamast instructions have arrived and are shown at the bottom of this posting. Note that they suggest doing things in a different order. Stay safe whatever you do.

GM4FVM Tennamast - succesfully re-cabled and fully working again (vertical in the foreground).

I had a plan to refurbish my Tennamast. It has been up for over ten years and I was aware that it could do with some attention. The plan (plan - well plan is a putting it a bit strong) was to strip it down, check the cables and pulleys, replace where necessary, clean the winch parts, take back the winch bodies to bare metal and repaint, lubricate the mast and rebuild.

During the Covid period I cannot summon any of the local like-minded amateurs to help me with the heavy lifting. Not that there are any locals who care about VHF-DX anyway.  A plan like that needs good weather too, as otherwise the whole thing needs taken apart and brought into the dry to work on it. 

It is possible for me to lift the mast. I picked it up and carried it when putting it up. I supposed I could take the car out of the garage for a while and work on it in there. If I took the antennas off the top pole that would break their waterproofing seals and they would need to go into the garage during such a long job anyway. So I was not about to do it right now. Next Spring seemed like a good time.

I started to notice trouble recently when I stabbed myself on the extension cable. I do not suffer well, so what really happened was that I pricked my finger on a frayed wire which had sprung out from the cable. Not quite a stab, but it hurt just the same. 

This did not particularly bother me much at the time, but the cable then frayed further and started to unravel in both directions. The overall strength of the cable was probably not much reduced, but this type of thing is the start of a chain of events which ends eventually with the cable giving way. So I would need to take action sooner than I had envisaged.

It has to be said that even if the cable did eventually give way, as it the extension cable and not the tilt over luffing cable all that would happen would be that the two sections would telescope together. If it did happen that would probably not be sudden. Most likely the cable would unravel, stretch, and lengthen, which would be obvious as it would no longer extend properly. But you have to be safe and if there is any weakness I would rather change the cable. Anyway, there would be less chance to stab myself with a new cable. 

Strands of wire peeling off the extension cable (seen after removal)
Stuff happens. Ten years is not bad for a cable. I raise and lower this mast a lot. As it is normally down by default, it is usually extended and lowered twice a day. I have read that some people get twenty years out of a cable, but they seem to leave their mast either up or down most of the time (like my CUG mast).

October isn't the best time to do this and in the event the original plan never happened. As usual, something else happens. I decided to move my refurbishment forward and start now, but it turned out to be a bit less comprehensive.

I ordered a new cable and pulleys from Tennamast. I did not need to buy the Tennamast replacement cable as I could have bought similar cables and pulleys more cheaply at the ship chandlers in nearby Eyemouth. I bought the Tennamast ones for convenience. The cable has a loop neatly made at one end and the correct size replacements bolts and spring washers. I did not think that I needed the bolt and washers, but it turned out that I did. I could not see how the top pulley had fared and it probably needed replacement. I did not want to be stuck in the middle of the job unable to source the right sized pulley.

Anyway, due to a slight mix up at the far end, the cable arrived without the pulleys. Also late were the instructions for changing the cable. I found a set of instructions on the internet from GD3YEO (here) but that was for a three section mast. Having looked at that I realised that the two section mast might be lower but it is much simpler to work on.

In any case, GD3YEO's experience encouraged me. At this stage I only had the cable and I could wait for the other bits. However, it was a nice day, so why waste the weather? I decided, at 13:00, to spend the afternoon starting the long refurbishment process by taking down the antennas, masthead amplifiers and rotator, storing them in the garage in preparation and sealing the coax ends against the rain. Then, when the other bits arrived, I would be ready to start my task. The downside was that as the year draws on the chance to put the thing back up would get less, and I might get stuck with it in the garage.

It wasn't to be like that. When I got outside I hatched another plan. I wondered if I could take the antennas and preamps off as one piece and not remove the coax and seals. Would that be too heavy for me alone to lift off in one go? No, as it turned out. Then I took off the rotator and left it connected. 

Given that I hoped to have an hour or two of good weather, why not try to change just the cable itself? I reckoned I would have to work alone because Mrs FVM has injured her rib, and anyway she was working from home to make some money to pay the shack electricity bill. She said she was "busy".

I was a bit surprised to find, once I removed the top and bottom mast sections from the rotator, that the SPID rotator bolts had cut their way into the thick wall tube I was using. I had been having a problem with the SPID losing alignment (more on that some other time, but I have solved it). During that period I tightened the bolts very tight to avoid any turning in the wind. 

The SPID locator bolts had cut into the alloy tubes
Although this extra tightening proved unnecessary, because of it the bolts were cutting their way into the alloy tube. This is a better outcome than distorting the tube, which was what I had feared might happen. Anyway, it looks OK to leave it as it is. Oddly enough I had considered making one or two holes in the tube to securely locate the bolts, but that seems to be happening without me using the drill.

Tennamast recommend steel tube but I go for lightness ...

Without the instructions I was flying blind, but why not try to press on? If anything resulted in me getting stuck I could just take off the coax, park the bits in the garage, and wait for the other parts. 

By various dodges I was able to partly extend the mast, tip it over, loosened (but did not fully remove) the stop bolt, undid the upper pulley bolt enough to remove the top pulley and then pulled the top section out of the bottom section.

Upper mast section removed, revealing corroded cable bolt

It was now clear that the bolt and nut holding the cable on to the upper section were corroded and slightly loose. The spring washer had gone rather limp. The replacement cable had a new bolt and nut, plus a new spring washer.
Fitting the new cable calls for three hands, including one for the camera

GD3YEO's report suggests this an even harder task on the three section mast.

The photo shows the stop heel on the bottom of the upper mast section. The stop bolt is mounted in the middle of the lower section, and thus passes the cable nut along the centre line of the mast as you crank it up to maximum. The significance of this became apparent later. Anyway, there is only one way to put the mast back together as the heel only goes in one way if it is to fit past the pulley, never mind catch on the stop bolt.

At this stage I pulled the new cable through with the old cable. This turned out to be important, as it meant that the cable was in place before putting the pulley back. It was clear to me which way the cable went over the pulley and down the lower section. Later I found out that the Tennamast instructions suggest doing it differently.

New cable simply passed through old cable loop, bound up and pulled through the mast.

As the new top pulley had not arrived yet I took the old one and washed it in soapy water to remove oily deposits. Tenna use nylon pulleys and it looked reasonably OK after ten years. I will replace both the pulleys at some other stage.

It gets a bit fiddly now and I may have got something slightly wrong which I had to correct later.

I now pushed the upper section back into the bottom section far enough to leave a loop of wire at the top to thread round the top pulley. I then put back the pulley on its bolt and the stop bolt. I would probably have been better to leave the stop bolt working but a bit loose until the cable was through the pulley and pulled really taut.

Once the cable was over the pulley I pushed everything together, checked that I could not pull the top section out of the bottom section, and turned it vertical for tests. Everything was working but it seemed a bit stiff. When fully up the top section jammed slightly, but with no weight on the top this was not a complete surprise.

When I turned the mast vertical I heard something sliding down the inside of the tubes. This was complete red-herring, and probably a stone or something irrelevant. I panicked, thinking there might be some sort of bush between the top pulley and the bolt, as there was a lot of play in that (though I had checked before and I could see the top pulley turning). 

So I phoned Tenna who reassured me on the top pulley issue. However, they said that the only likely issue I might have would be if the cable had become trapped on the "wrong side" of the stop bolt. It should run directly up from the bottom pulley to the top pulley, passing the side of the heel on the top section as it went, over the pulley and down straight to the fixing point. D'oh, of course. They advised me to get someone to push the top section in and then loosen the stop bolt to allow the cable to fall into its proper path under tension.

I decided that this was serious enough to call Mrs FVM away from her work to help. She found a ten minute gap and struggled against her injury into the garden to help. With only one side of her body usable and with great pain, she pushed the mast down while I loosened the bolt. I thought she could have been a bit more cheerful about it, but there was a "twanging" sound as I undid the stop bolt so it seemed to work. Anyway, I let her go back to get on with whatever it is she does.

After that it seemed to run very freely. I use a battery powered drill to work the winches, though it was not fully charged as I was not expecting to do this job right now. I had done so much work that both the drill batteries were back on charge and so I ended up using a mini electric screwdriver to tilt the mast back and forth and raise and lower it. Even though there was no weight on the top this was a good sign. If a puny electric screwdriver can wind a mast up and down it must be running freely. 

I lubricated the mast sections and did various tests. It was clear that there was no danger of the top pulling out of the bottom section (it is fail safe, even if the top bolt failed the heel would catch on the pulley). Anyway, the cable could not pull itself higher than the pulley which is inside the bottom section. Better to check everything anyway. 

It was great to see the nice new cable, even in my now rusty and dowdy winch. The refurbishment still needs to be done later, but everything has been checked, cleaned and lubricated, and nothing amiss was found.

Nice new cable in my rusty old winch, and still with original bottom pulley.

After that I slotted the rotator back, then the antennas and preamps, which were still on the top pole. After a few quick tests it was clear that everything was working.

I would estimate that the whole job took 90 minutes for the mast part. Taking the antennas and rotator off and then putting them back on took over an hour because I left them connected and they were heavy for one person working alone. However, doing that avoided resealing the coax.

It saved time, but keeping the antennas and so forth on their pole made the lifts very heavy for me alone. I had a sore shoulder for a couple of days. Nevertheless, the job was done almost entirely single handedly.

I did not set out intending to get the whole cable job done in one afternoon. That idea just emerged as I worked. Doing it this way means that I still need to do some work on the winches and replace the pulleys at some later stage, probably next year. But I have removed the weakened cable and it taught me the detail of how the mast works. I would be happy to work on it again.

Tenna were very helpful. The tip about checking that the cable was on the right side of the stop bolt was really important.

The two pulleys and the instructions have now arrived. The instructions show a different order for doing things and are posted below. As usual click to enlarge any of the images.



My Tenna mast is sturdy and well made. I rather enjoyed taking it apart and putting it back together again, even if the job is not complete yet. Now I know that the old frayed cable is not going to stick into my hand and "stab" me.

73

Jim

GM4FVM




Thursday, 1 October 2020

Main and sub band USB audio output with the IC-9700.

Two postings ago (here) I explained how I was collecting a second audio stream from the IC-9700 to route to a second decoder in my computer, allowing dual band FT8 (etc) decoding.

I did this by using an analogue audio stream and it proves that it works.

I had read in a review that the IC-9700 creates one digital stream for the computer via the USB and that any second stream for the sub band would need to be taken out by analogue audio. I believed that when I read it. The Icom manual said nothing about it at all, and certainly never suggested that a second audio stream was available via the sound card and USB.

Imagine my surprise then when Greggor posted a comment on an earlier posting in this blog here to say that it is possible to get both streams via the USB. Greggor's comment was:-

Do you mean you can't get the sub band audio through the inbuilt sound card ? By default - windows sees the inbuilt sound card as a MONO microphone. If you go into the advanced audio properties and force this to 2 channel - you will have main and sub coming through. Left & Right.

https://klop.solutions/stereo-audio-from-ic-9700/

Yes, I did mean that at the time, but you are right, this is possible, and I have now done it. The link given my Greggor sets this out. I did it my way by working it out myself before reading the link, just to see if I could do it. I could do it, and it works. I explain what I did below. Thanks Greggor.

First, I read all of the IC-9700 manual and advanced manual. There I could find nothing to say that this was possible, nor anything else about the audio output via the USB. The whole subject is missing. I suppose this may be because Icom are not responsible for Microsoft/ Apple/ anybody else's operating system, our computer layouts or our USB drivers (though they do provide USB drivers). If that had been in the manual I might have noticed it by now.

However, I am not going to let Icom off that easily. They did not need to understand anything about my computer to indicate in the manual that this was POSSIBLE. All they needed to say is that two digital audio streams exist, or are enabled via the sound card and USB. If that is in those manuals I cannot find it.

This second audio feed has been coming out of the IC-9700 via the USB for more than a year, and I have been ignoring it because I did not know it was there.

Moving on, once Greggor pointed this out I set about proving it my way. That means I understand how to do it. As usual I went to Control Panel and selected Sound .... (click on the images to enlarge them if you need to)

"Control Panel" in Windows with the "Small Icons" view.
As always I view Control Panel in "Small Icons" view as it makes it easier to see everything plus I am old enough to remember when it always looked like that. You can get to the sound settings other ways, but this is the way I do it. I like defaulting back to Control Panel as it gives easy access to both "Sound" for this type of thing and "Device Manager" for COM ports and lost USB connections.

OK, selecting "Sound" allows me then to select "Recording" which is where the audio comes in, and then the USB input I am using for the IC-9700 - in my case "Microphone USB Audio". I then selected the "Advanced" tab where I found that Windows has by default selected a one channel audio stream. Change it to two channel, in my case "2 channel, 16bit, 48000hz (DVD Quality)". I clicked "Apply" and I had enabled main band on one channel and sub band on the other channel.

Selecting a two channel stream in the "Advanced" tab for the USB sound card input

Then I shut everything down in the Control Panel.

Although I use Windows, I expect that Apple or other operating systems have similar option screens.

My next thing to figure out was which channel was which. Effectively we are using a stereo sound stream for two different signals. One band is "right" and the other is "left".

A quick bit of juggling showed me that, for me anyway, main band is left. In WSJT "Settings" that worked when set to "Mono" by default, but I set it to "Left" and it also works there.

Channel selection in WSJT-X - Input "Left" or "Mono" both gave me main band.
As my sub band decoding is done in MSHV I needed to set it up to right channel. That setting is in "Options" then "Sound settings". Just click "Right Channel".
Channel selection in the MSHV Sound Settings tab
Job done. Not only does it work, but it works better than the analogue lash-up, and saves another sound card and cable, plus I get my on-board loud speaker back. By avoiding a digital- analogue- digital conversion there is less noise.
GB3NGI on 144MHz via the (now-digital) sub-band

So now thanks to Greggor I have a fully digital 2-band decoding receiver. In my case this is 144 and 1296 MHz bands simultaneously. You could use any two bands, but not two frequencies in a single band.

The manual does not say it is not possible to have two digital audio streams, it does not say it is possible, it just does not cover it at all. Yet there are pages and pages of irrelevant bull-crap about logging what speed your radio is moving at, or what height the receiver is, while surely the IC-9700 is more likely to be used as a fixed DX, moonbounce and satellite transceiver. Still, you never know - I might take up using DStar repeaters from a hot air balloon. That is the obvious next step for me to take in my radio journey. 

If I was in a hot air ballon I might be able to work Montrose (read the whole blog history to understand that one).

How any cross-band digital mode operator could have worked efficiently without this knowledge I do not know.

So thank you to Greggor and I have now got this resolved and I am back to an all-digital system.

It almost seems that the S/N on the separate main band stream is better than the figures on the mono settings for the single mono digital stream. 

Surely I am imagining that.

73

Jim

GM4FVM