Morse code decoding in CQ WW DX Contest CW

A few days ago I participated in one of my favorite contests on HF, CQ WW DX Contest-u CW. Actually, it was only the second time, since I joined this competition, however, I regularly try to go CQ WW DX Conest SSB, since I don't know "morse code"..

First attempts with a morse code decoder

Few years ago, when I purchased SDR FlexRadio 6300, I tried it for the first time. I don't have a log with me anymore, but with the help of the computer I made enough connections to do so, to be the first in the given category – all band even in a sweater. But then I made a fundamental mistake, I sent the wrong log. Reassigning the logo to one band category did not mean any success.

New destination for CQ WW DX Contest CW

But this time I wanted to change it. I remember, how I enjoyed it! It was definitely super easy to make a connection in CW mode compared to SSB, especially when a person broadcasts with reduced power to 5W.

Versatower antenna mast

My preparation started at the end of June, when I ordered a new Versatower – 12m mast from Poland and a 3-element 5-band direction indicator from SP7GXP. Everything was waiting for me at my home after my return from Asia. All that remained was to dig a huge hole, put in it 2 tons of gravel together with 26 bags of cement and the mast could stand. Here I have to thank Viliam OM0AAO, who helped me a lot with the mast and without whom I really couldn't have done it.

SP7GXP antenna

I built the turn signal myself. It was interesting, but I was surprised by the quality of the design of this SP7GXP antenna and I slowly put it on over the weekend. And I think, that I did a good job. The mayor of the village helped me put it on the mast, for which I am also very grateful. The two of us managed it in half an hour and I could spin it to my heart's content. See in the following photo, how does it look. And yes, the antenna is dimensionally larger than my house 🙂

om0rx qth

FAN antenna

Due to work busyness, I started preparing for the CW WW DX Contest CW only on Friday morning, so a few hours before it starts. I also wanted to make a FAN antenna for 160/80/40m. I started building it in the morning, but due to missing material, I didn't even have a way to hold it Wonderful article and simply - I couldn't keep up anymore. Although I measured honestly, each arm of the dipole and connected everything like that, as it should be, darkness came and I still didn't have the software installed and I wasn't even decided, what category will i go.

Luckily, I put in my vertical Butternut about a week before (80-10m) to the center of the garden, he added 12 radials and stretched the cable to the house.

I haven't even decided which category I will go for. I wanted to try all the bands and if I make more high quality connections on any one, so I would send only that, otherwise it would be all bands.


Powering the radio station with solar panels

To, will I go QRO, low-power or QRP was not on the table – I had to go QRP. Why? I live in a house, which is not connected to the mains and everything, what I consume I have to make myself. At the moment I only had available 3 solar panels with a theoretical maximum of 1.2kw, plus 3000W converter and 24V system: specifically a 280Ah battery (LifePo4). So I have some stored in the batteries 7 kW, usable approx 6,5 kW. In addition, I have a refrigerator with a freezer, the lights, router, laptop with monitor, and other appliances. And I'm not afraid of QRP – made a decent number of connections on SSB as well. It's not something new for me. Practically the whole contest I go only in S&P fashion and I never call, since as a QRP station I have little chance.

So I have antennas. Both work beautifully – turn signal for 20m – 10m and vertical I wanted to use on 80/40, and with a tuner if a couple of connections are possible even on 160m.


Technical, that is, as far as the antennas are concerned, I was equipped. I had a SunSDR2 Pro available as a TRCV – a small box, but great performance.

What is TCI Expert Electronics for??

About eight in the evening I started to "solve" the software side. In the previous competition – CQ WW DX SSB Contest it was easy. All I needed was ExpertSDR software on my MacBook Pro computer and RumLog, who understands him very well and communicates through TCI (Transceiver Control Interface), which is a special protocol developed by Expert Electronics, which simplifies everything – you don't need to bother with any COM ports or anything like that.

It is possible to compete without knowing Morse code (CW)?

Since this will be a competition, using mode, which I don't even control, I had to set up my system like this, so that I can effectively decode the morse code of other stations and at the same time answer them and make a proper connection with everything, what belongs to it.

Failure with SDR software, CW skimmer a N1MM+

First I tried to run an older Windows laptop 10, but when I wanted from him, so that the SDR software goes at the same time with N1MM+, so it just didn't work. It was very slow, and I'm not talking about the CW skimmer, which I wanted to use.

Solution with SDC software UT4LW

I had nothing else left, just take back my MacBook Pro and start configuring. Fortunately, I already had SDC software available ( from UT4LW, which has a built-in CW skimmer server and Rumlog ( by DL2RUM. As SDR software, only ExpertSDR software is usable and available for the SunSDR2 Pro radio. ( od Expert Electronics.

Working with RumLog software

What took me many hours of trial and experimentation was setting up the Rumlog software correctly to send CW.

TCI advantage

Actually, the entire SDC link + RumLog + ExpertSDR2 is extremely simple, since all 3 the softwares communicate via the TCI protocol. In ExpertSDR2 you only enable TCI, the same in SDC, it already knows what port it works on, so again it is one "tick" and in Rumlog the setting is very simple, see screenshots.

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Morse code broadcasting and Telnet server

But the problem arose when transmitting Morse code. As you can see in the following screenshot, the system is absolutely brilliant! I even used the second function of the SDC software, and that is the own telnet server!

Operating principle for decoding and transmitting Morse code

Then it worked as follows:

    • SDC decoded CW signals. It handled the entire CW part of the spectrum on a given band at once and I could tell by external tests, that it is better than the CW skimmer on Windows, which pleased me.
    • Individual stations were then stored in their own cluster in SDC, I then configured the Rumlog software, to simply not connect to an external cluster, but on my own.
    • Rumlog has yet another function – can move spots directly to ExpertSDR2 software, so you can see it there as well, what do you need, what no, where anyone is located, simply great!

In Rumlog, you can configure various CW macros and broadcast efficiently using only the keyboard, you don't even need a CW key (same as in N1MM+).


Transmitting morse code from the keyboard

As I write, I struggled with macros in Rumlog. It just didn't do it for me, which had and after hours of trying (as for the manual, is very weak in this and doesn't explain much). I finally found out, that just put for each macro "[Run]” and my problem was solved.
During the entire competition, he used only 2 macros. It was absolutely enough, and it was these two in particular:
[My Call] [Run]
[RST] [Number] TU [Run]

Awesome, Nope? Rumlog had one more amazing feature, a to to, that it showed the decoded station directly in the logging window, so I didn't even have to look anywhere else. During the entire competition, I made do with two windows – band map and login window. I saw all the stations in the band-map, what custer moved me, which was decoded by the CW skimmer in the SDC software. It was a matter of course, that Rumlog already knew which ones I was missing, which I did, which are the multiplier – oh amazing, everything is nicely color coded.

The advantage of own cluster

And another huge advantage was that, that I had nothing in the cluster, what my antenna didn't hear and what my software didn't decode. And it was confirmed for me 100% team, that practically 99% I did the stations, some were more difficult, I had to fight the QRP signal in a pile-up, but to my surprise, I would say, that 50% I made the connection on the first call.

The following screenshot will show you everything in one place – band map, logging window, SDR software. You can also see how it is decoded there, right in the window, where the QSO is recorded. As for the color resolution of the contacts, red color means, that I have already made a connection with the given station, green, that I need it and blue, that it is some kind of multiplier, either a zone or a new country. So I knew very well, which connections I need to focus on.


How the competition actually went on my side?

I clicked on the station in the band map, with whom I wanted to make a connection.

I waited until it ended the connection with the previous station, most ended with "TU K4ZD", i.e. thank you and shout out. then i knew, that it's my time and I pressed the macro with “ ”

A good feature of the software was, that he knew, at what speed the given station broadcasts and set it automatically! Well, it's not great? So I broadcast from 25wpm to 38, I mostly noticed, that most stations went around 30wpm. Russian stations went much faster and 38wpm was not unusual.

I read and listened after my brand aired, whether the given station will answer me. Most accepted my entire brand the first time. Others gave e.g. “RX?” or “OM?”, possibly another combination or even purely "X?”

I knew, that it is then my time and I called the macro again.

I'm back already “received e.g. “599 5 TU”, but mostly it was "5NN 5 HERE" which is a little shorter.
To that I pressed the key with the second macro and answered “599 15 TU”.

And it was! I still waited, whether by chance the opposing station does not request my answer again, but usually on 95% it passed the first time and I was able to move on – back to the point 1!

And not, I don't really know morse code (anybody here, who will help me learn it? The interest is there). Don't think so, that it can be managed without "listening", especially such a competition.

There were many connections, when my CW skimmer didn't decode everything correctly, either due to QRM or QRN. In that case, I really had to recognize my brand and the rest. Since it was repeated, it was possible, see you my. Especially in pile-ups it was difficult and I logged quite a few connections without seeing it decoded, but already from hearing (Yes, even at 30wpm) I knew, that they took me and put TU at the end, etc. …


The CQ WW DX Contest is also about fatigue and endurance – evaluation

In the end it turned out that way, that I changed over after the station 36 hours from 48, he made 1509 connections on all bands, that is, only a couple at 160m, since I didn't have an antenna for that band (7 made a connection with there).

But I was surprised by my vertical, from whom I did not expect it, what he allowed me to do. See screenshot from my statistics, but I will write, that I actually made the most connections on 80m, a to 494! My second band was 40m, where I did 401 connection. So yes, you can see here too, that with a simple antenna and QRP performance in competition you can make hundreds of connections.

The turn signal worked great too – she already confirmed that to me in the previous competition. It is 12m high, but it has its advantages and disadvantages. You all know the benefits, but the disadvantage was its directionality. You have to spin and that wastes a lot of time and I definitely knew how to make connections faster on 80/40 bands like on 20-10. When I didn't have the turn signal pointing in the given direction, I didn't even know, is there anyone interesting?, since I did not use an external cluster. Here you need to use your knowledge and experience, you must know, which direction is open at that time, where to direct the antenna to get the most connections and points, etc. But this article cannot cover everything, so hopefully next time also about this.

I have to write a conclusion, that I liked it. 1500 I really didn't expect the connection, that i will do. I'm already looking forward to the next CW contest.

If anyone has any questions about software and antennas, I will be happy to answer them, feel free to comment on this article.

In conclusion, I still want to write, that I'm glad, that finally, as a native Slovak, I could broadcast from my own QTH in Slovakia. And I broadcast with a smile. The previous competitions I went from Wales (I am GW MW0JRX, MC0SHL) and from Australia (VK ako VK8DX, VK5RK a VK2YI). I "stopped" a couple of times in Slovakia and broadcast with Viliam OM0AAO, for which I am very grateful. well thank you!


73! by Oliver OM0RX

I am attaching the final screenshot taken a few seconds after the competition ended.


And for those who like to look at different screens, I have statistics here:

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Jacob OM1WS
Jacob OM1WS
1 a month ago

You have a beautiful QTH, I also have occasional QTH in Podkylava

1 a month ago

Very interesting and inspiring article. Thank you and I wish you much success on the pasture.

Ondrej OM4DW
Ondrej OM4DW
1 a month ago

If I can give you some advice, with QRP, don't call big guns quickly. Especially in bad sulphurizing conditions and on the lower bands, you can go further slowly. In large KV contests, so to the extent 24 – 30 wpm, more is counterproductive. Big guns go faster, because they are strong and it will be poured out on them. A prave, ked neodsypa, neither should they walk unnecessarily fast. What you mention is already a bad habit among Russians, when they call barren CQ s 38 wpm. Many opposition stations are not even able to take it, get wet in bad conditions (weak signal, shaken through sev. pol).

1 a month ago

A little advice about the power supply.
Ak mas complete solar system, which has performance and capacity, if you list, so I recommend a small power plant that has a combined starting system.

Popis, how to achieve it cheaply and by yourself.
So EC can be started manually, with cord and battery.
To add to the start of the dial small control keys, starts reliably within 100m.
Just add the relay, one to turn on the ignition and the other to engage the starter,
Tin module, which can be set for one button permanently on/off and the other button as a button, to engage the starter.
Extension drum, at least 20m 3x 1.5mm cross-section, so that EC does not roar near the cottage.

Entry into the solar system, charging, here I will give the following recommendation.
Do not use switched sources, or chargers, but..
If you have a powerful MPPT converter, so to the input money changer, for panels, it is good to connect through a high-quality separating transformer and a classic rectifier with filtration, charging from EC using one isolation diode.
You just have to stick to that, what is the maximum input voltage for the MPPT regulator, that is, the open-circuit voltage on the tap from the rectifier, let the voltage not be unnecessarily higher.
The regulator will take care of it, according to your own needs, optimal EC tasks, a few behu EC, it will not go to waste.
The advantage of the trap is, from galvanically 100% EC exit section, you will also remove possible interference, which would be on a simple, or even the electronic regulator could have occurred and pushed into the system from EC to “on-board network” island system.

When you watch the tension, or status on MPPT, you know when you can turn off EC, or when to turn it on, maybe in reality it will run at most 3 times in 24 hours, two at a time, max 3 hours, Probably twice at night and once during the day, if the system is well dimensioned, because EC if it is 1-1.5kW, transformer at least 1kW, so in this execution, recharge the battery quite quickly.

It is ideal, if as a trafak, you use a bigger transformer, or a finished old charger, for basic batteries, or emergency lighting, possibly traction batteries of telephone exchanges, etc.
And mass solar 1,2kWp, so the changer probably has enough dimensions, it shouldn't be a big problem to connect it.

EC is also suitable for other small jobs,when inverter and solar are not enough (worker.. karbobruska, mie sack.. lack of light in winter)

The cheapest power plant, I used to have parkside from Lidl,WHY 2800 A1. she stopped me 150 euro, unpacked at the store. The pipe wrench was missing, a funnel and probably also a funnel.
One day, the modified one was stolen from my car, but I got another one for advertising, I didn't edit here, there was neither time nor need.
When I was doing various jobs outside on site, where there is no electricity. connection and solar was not necessary.

I bought a kit for the power plant from AliExpress, for electric starter, it's almost a primitive thing, the rotor of the ignition magneto changes, where is the ring gear for the starter, the starter itself and the control box, (a piece of sheet metal with a boy)
The set is also made of aluminum 2 x two-button keyboard with pull-out antenna and receiver, which had a 12V power supply and two relays, which could be set individually either to bistable, or monostable output control.
It is very comfortable, they have very expensive aggregates, for example Honda, or other, because the boy in the bag, during idle work, it makes it possible not to let the aggregate run unnecessarily, but start it as needed, for the time necessary for the dance.
The first start must be done manually anyway, because you have to turn on the choke and the flashlight usually dies after a long time and does not run smoothly.
After the first start and about half an hour of running, the battery in the EC will now be charged, at the next start even after several hours, if it's not cold, there is no need to turn on the throttle, at least that's the experience.

The central PSE 2800 A1, she managed to power the welding inverter as well, out in the field and even a plasma cutter, but first the compressor had to be pressurized and then the plasma had to be ignited.
It is basically a copy of a copy of the Honda engine and the entire wiring, and regulation, it's like a Honda. It has consistently proven to be safe at the exit from 12A, full stop around 10 hours. (connected dryer 2.2 Kw)
At that time, nothing could be found cheaper.
Other ECs are certainly better, rent from honda, but very expensive.
Gude is also a good brand, especially those with big wheels, for construction.
They are not that effective, but they have a 1F output of around 3kW.
But I don't know, what remote start kit would need to be installed there.

For permanent and long-term operation, instead of gasoline, I also recommend getting a carburetor for PB from Alika, Pre EC
If you happen to have a refillable one (for an LPG refillable bottle, for caravans on the pump, original) so for the price of refueled LPG, you have cheaper electricity from EC today, like from a drawer, for non-residential premises..
Exchangeable bottles are not worth dealing with, because gas in exchangeable bottles, it is 3 times more expensive, than tanked LPG and it usually comes out cheaper. benzin natural.

Artur SP3VSS
1 a month ago

A beautiful place for amateur radio work. Congratulations!
Very good article.

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