Thursday, 2 November 2017

Great October, data modes, noisy modems and getting angry,

I feel the need to sound off about the ridiculous nonsense talked about data modes by people who don't know anything about them. Indeed, I feel abused as I am one who often says that amateur radio is open to all, yet it is me who is getting insulted by others who seem to suggest that using data modes is "cheating".

I have been reading this sort of nonsense in Practical Wireless magazine where there is talk of the need for "proper" QSOs and fears expressed about new data modes undermining the results obtained during great Dx periods of yesteryear. Yes, like we should accept less Dx to preserve the history of the achievements of the Editor of Practical Wireless magazine.

Having cancelled my subscription to PW in protest, I find local amateurs droning on in similar vein. At a recent tea with some locals I had to explain that data modes like FT8 are radio and not internet linking modes. "How do you do it then?" they asked. "First you get a radio and an antenna", I replied. "Oh, I didn't know you used a radio for that". I think they are confusing digital voice modes such as D-Star with non-internet communication - even though you need a radio for that too. I had to explain how I made these QSOs in a one word answer - "radio".

I also got told that these local amateurs did not use computers or digital anything, which is interesting as they both use digital signal processing in their rigs.

The depressing thing was that I knew the outcome of this conversation before I met them. Almost word for word their reaction was infuriatingly predictable. They know nothing about data modes, they do not want to hear about them, and they regard them as cheating. Actually, they regard beam antennas and linear amplifiers as cheating too. They are entitled to their view, but surely so am I.

For now I am leaving this to fester in my mind until later.

In the meantime, Bri, G0MJI, has summed up the topic well here.

This is a subject I need to come back to. I keep saying that there is enough room in this hobby for all interests, but others seem to consider that my interests are a threat to their idea of amateur radio.

I am old enough to remember people saying at different times that SSB, FM, repeaters, satellites and commercial rigs were going to be the death of amateur radio too.

It has been a great month. My 6m tally for the first four weeks was this ..
6m contacts at GM4FVM in the first 4 weeks of October 2017
I find this result surprising as only one QSO was on meteor scatter and all the rest were on Es. As I explained before there were several increases in X-ray energy reaching the Earth. Then towards the end of the month there was an event I call "geomagnetic activity short of an aurora". Apparently it is called "pre-auroral enhancement" by those in the know. I am not sure that is a good expression for an event where there was no aurora. Anyway, lots of nice Es at a time when the prediction sites said nothing was expected. Then they cover their mistakes by ignoring the resulting openings.

For 10m it was even better, with E and F-layer openings bringing me new DXCCs in the shape of India, Bosnia and Gibraltar amongst others. Turkmenistan was an interesting one, as most sources say that amateur radio has been banned in that jurisdiction. Maybe that is one I cannot claim.
12m contacts at GM4FVM in October 2017
Both these results run contrary to the commonly-held view. The commonly held view is that 6m Es is a summer only thing, and also with the solar flux level down about 75 there is no point even trying 10m.

As I suggested last time, the commonly held view is often wrong. I keep reading articles about nothing being workable with the SFI in the 70s.

There are two things which seem to arise here:-

1) Although almost all of those contacts were made on FT8, looking back over previous years suggests that similar results were also possible on JT65 and even more so on JT9. I looked at a PY station with interest to find that I had worked them before in February 2016, on JT65. FT8 is not better than JT65 or JT9 in efficiency terms, what it offers is a quicker QSO. Lazy operators like quicker QSOs, so it is hugely popular. If it is popular there is more chance of me making contacts using it. More on this issue in a later post.

2) I am not going to suggest that November will be as good. It might be, but the only way to find out is to look and see. There is no substitute in amateur radio for being on the bands, calling CQ. If you are looking for a prediction from me forget it. As a modestly powered station with simple antennas I get my best results when the big guns are sitting with their feet up. So when the bands opened in October I make hay, knowing that most "weighty" operators are following the lemming idea that at this stage there is nothing to work. I might sit and hear nothing in November, but I will not mind. Why not come on the bands and join me?

This does not just happen by itself. I have finally installed the M&P Hyperflex co-ax on my 6m beam, and for the moment I have put back my 5 element PowABeam in place of the 3 ele Sirio.

I have also replaced the half wave vertical dipole (Sirio Gainmaster HW) with the 5/8th wave version (Sirio Gainmaster Classic), thereby reversing my decision to change them last year. This immediately improved 10m  performance and gave me back 12m. I am very fond on the 12m band. I have even dug out my LDG IT-100 ATU to use with the IC-7100.
IC7100 (left) and LDG IT-100 (right)
The IT-100 works well with the IC-7100. It is controlled direct from the rig TUNER/CALL button on the IC7100's control head. Although rated for 125W of SSB, the IT-100 is only capable of 35W of data modes. I am fairly certain this limit applies to modes such as digital voice, whereas in operation I find that 15 second bursts of FT8 pose it no problems at all. We shall see!
My relentless pursuit of a low noise environment goes on. Some time ago I pointed the finger at BT Openreach's fibre modem.
When "fibre to cabinet" broadband came to this village I changed over broadband service provider, leaving BT. At that time the network operator, BT Openreach, did not permit anyone to connect a third party router direct to the copper wires which link to the cabinet. I should perhaps explain that in the UK fibre to the premises is only available in certain limited areas, mostly big cities. Elsewhere you have to use your existing twisted pair telephone cable to reach the fibre enabled street cabinet. And that means that your broadband provider is, of necessity, BT Openreach, and you have to follow their procedures.

Fibre to cabinet is in fact fairly effective, increasing my broadband speed by a factor of 5. However, my broadband provider had to get BT Openreach to provide the modem pictured above, and then I had to connect their router to it.

None of this would matter much had the BT Openreach modem been quiet, but it certainly was not. I got strong birdies all across the VHF spectrum. For a long time I chased around adding screened cables and changing power supplies before realising that the noise was coming out of the box itself, and particularly out of the ethernet sockets. Eventually I calmed it down by adding aluminium foil ("Bacofoil") screening over the sockets. That was better but still not perfect.

There are millions of these modems in UK homes. That is hardly surprising because BT Openreach insisted on them, and the only way of avoiding them was to buy your internet from Openreach's parent company, BT. BT could provide you with an integrated modem/router, but no other broadband provider could. And as BT Openreach owned the network, that was that.

I thought about screening the entire modem. The snag with this is that the Openreach modem has a fearful reputation for overheating. It even came with a sticker warning me not to obstruct the vents. MM0XXL donated a large screened box with built in power supply and a fan so that I could both screen it and ventilate it at the same time.

Then eventually I discovered, by chance, that BT Openreach were no longer offering to maintain the modems. Further digging revealed that a year before this Openreach had dropped their requirement that this device had to come between any non-BT Router and their wires. So I was now free to buy an integrated router which would plug directly into the twisted pair.

I had already spent quite a lot of money on a nice fast and secure router which would cost a fortune to replace. So I decided to buy a simple TP-Link combined router, configure it to run as a modem, and then feed my router with a screened ethernet cable. This, combined with screened phone cable from the main BT Openreach box where the line enters the house, produced instant radio silence at a cost of under £30. My broadband speed has gone up 30% too!
Unusual styling of the TP Link router now acting as a modem.
It looks a bit odd. It has many many vents and slits all over it, but it does not radiate any RF that affects me. Problem solved.

Openreach had dropped their requirement to use their modem long before I heard about it. I must have had one of the last ones fitted. But it is solved now.
There are new versions of WSJT-X and MSHV to report on.

WSJT-X v1.8.0 is now an official stable release, replacing the trial rc2 version. Various improvements have been made. It is now possible to save your frequency list, something which I will find handy as I had to laboriously delete lots of entries from it every time I updated in the past. This became available in rc2, and now the full list appears or you can re-install it by clicking "reset". Very handy.

A bit odder is the way clicking on the waterfall affects your operating frequency. In the past you could select "Lock Tx=Rx", which was pretty self explanatory. Now that box has disappeared and the options look like this:-
"Hold Tx Freq" allows you to keep your Tx frequency fixed while clicking on text to answer a call on another frequency inside the waterfall. This is to allow the use of split frequencies.

The use of splits within the filter (i.e. within the waterfall, not on a different VFO setting) has mushroomed since FT8 became popular. DX stations, i.e. those lucky enough to handle pile-ups (is that lucky?), call CQ and take calls from all over the waterfall. So you can call a DX station from any point in your SSB filter, and the DX station will generally reply on the frequency they called on. The reason this is done is that if the DX station listened on their own frequency they would not get a decode due to the high level of QRM there. This way they can hear stations calling them in the clear.

So that is great for Dx operators, but for the rest of us the outcome is a bit more tricky. Clicking on the waterfall now moves only the rx frequency. To move the tx to the same frequency press shift on your keyboard and click on the mouse button again. Or click the Tx<Rx box. If you press AltGr on the keyboard and click on the mouse button then both tx and Rx move together (as if the old Tx=Rx Lock button was selected). This is how I find it works with a UK standard QWERTY setup, anyway.

So if you hold AltGr key down on the keyboard, then clicking on the waterfall moves both frequencies just like it used to do with the Tx=Rx lock operating.

No doubt all this will become second nature after a while.

It would seem more sensible to me if things worked the way most of us operate - on a single frequency - with the options for the others. After all, if everbody used a split frequency we would all occupy twice the bandwidth.

MSHV went through an odd stage of development when, in MSHV 1.51, the FT8 mode was removed as that mode was still in development. This was no doubt because WSJT-X 1.8.0 was in testing. Now that WSJT-X 1.8.0 is on stable release I had hoped that MSHV would restore FT8. This has indeed happened. MSHV 1.53 includes FT8 as well as retaining PI4. Whether MSHV is better or worse at decoding PI4 than PI-Rx is something I am unsure about, but receiving PI4 certainly works on MSHV.

MSHV still runs with a lighter processor load here than WSJT-X, and that still matters to me until such time as I upgrade my PCs. MSHV also has a full range of watchdog timeout options, able to be defined in either time or number of Tx periods.
Well, back watching to the exciting end of Masterchef Australia 2017. Very exciting.

Perhaps I should collect some mushrooms first.

I think that Sophie Ellis-Bextor spoke to every antenna experimenter when she sang

"If this ain't DX ...
.. why does it sound so weak?"

Ah, Groovejet. My favourite airline.



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