Tuesday, October 31, 2017

#cqww PA6AA contest report

Event: CQWW DX SSB contest 2017
Section: HIGH power MULTI TWO
Logger: N1MM+ 
Station: 2x Elecraft K3 + amplifiers 400W
Antennas: Inverted-L 160m, verticals 80/40m, dipoles 80/40m, FB23. Hex beam, 3 band vertical.

Well, some people think the amateurradio hobby is a bit anti social. Since many are operating from a small room alone, they all do it for their own benefit. However if you do some teamwork, like we did this weekend, it is a nice social event. We had a great team for shure and all experienced radio operators that had fun.

Contest fieldday style
A house was rented at a great location at the northern coast here and about 50m from the dyke and 100m from the sea, the surrounding all flat land with only a few farms as neighbours kilometers away. The house has a nice field which is excellent for wire antenna's like we had.

The rest of the team started friday morning building the antennas, unfortenately I had no time to join them. All antennas were fieldday style, wires and small beams. I attended the team saturdaymorning.

What I especially liked is the free style operating, no time blocks or planning. If you got tired or hungry another operator took your place and that worked very well for us. Same for band switching, we all are experienced operators and know when a band is possible open or not. No planning just common sense and it worked.

Broken hexbeam
The only thing that didn't really work was the extreme weather. Windgusts from about 100 km/h which destroyed the hexbeam and the inverted-L for 160m saturday night. Especially the lost 160m antenna was a loss of points.

When I arrived sundaymorning I already saw the damage and after all we managed to put the FB23 into the scaffold together. Luckely a spare mast saved the inverted-L so we could continue 160m sunday evening. A 3 band vertical was placed as well which actually didn't do a bad job.

If you, by any chance, had a look at cqcontest.net you see we claim place 19 worldwide very close to our biggest concurrent PI4M. Actually we were very close at the start of the contest but in the end they had a few more multipliers and probabely more 3 pointers. PI4M however used a beam on a large tower and a moxon beam on 40m. So we were not surprised...

Friday, October 27, 2017

#cqww fun with PA6AA

I was just thinking at what moment I met some of these guys first time. The exact years are unknown but I met Peter PA4O and Bernard PB7Z  already on air at the start of the nineties of last century. 25 years ago we were on 11m (CB, 27MC) and not even thinking about legal hamradio. I had never thought I would colaborate with them in the CQWW SSB contest 25 years later.

Find our bio at: www.qrz.com/db/pa6aa

Well, actually I didn't have the time to help them really with building the station. The only thing I could do is renting the scaffold from my job and get it to them. Fortunate I had another customer in the area that had to be visited and so I could get there within time for them to set it up. The other guys did the hard work actually. Hopefully I can do some more work in the weekend. Especially contesting of course.

The nice thing is that the house that is rented is very near to the sea and far from any other villages and disturbing interference. It is the open field which is very flat. Only at the north is a 10m high dyke. From experience I know that it will give some attenuation to the north, but since the sea is at the other side that will compensate. The nice thing is that it will give some gain into the other direction. How do I know? Well from experience with a CB radio on my bicycle long long time ago. I've been cycling in the area in the eighties actually and did some tests back then on the dyke and below the dyke. Signals became stronger in the south direction when I cycled below the dyke.
Of course that was on 27MHz, so I don't know for other bands but expect it will be similair.

We will see if this will be in our benefit....

Hope to meet you in the contest!!

Thursday, October 26, 2017

Fast propagation research with FT8

I think it is now evident FT8 is the most interesting digimode today for research of realtime propagation. And it is fast! Really fast! However for good research you need to receive and to transmit as propagation is not always reciproke. My idea was:

Start at band 10m and first receive 2x 15sec. timeslots to see were you can transmit in the waterfall. Then 3x transmit 15sec and 3x receive 15sec, In total 120sec=2 minutes in total for each band.
You can scan 10m-160m in 10x2=20 minutes and you got an idea how bands are at that moment.

Well, I can tell those 20 minutes became longer after all when I started this experiment as I used CQ for transmission and got stations back to me on some bands. Besides that I noticed 5T2AI from Mauritania on 20m FT8 with a strong signal which would be a new one for me. So I returned to 20m before I made the screenshots and worked 5T2AI for a second ATNO this year.

A overview from about 18:00 UTC yesterday evening:

Complete picture all bands

10m, I immidiatly had response. But no DX propagation.

12m, nothing at all. PSK reporter comes back with all stations monitoring 12m at that time.

15m, I didn't hear anything but they heard me! Typical non reciproke propagation.


20m looks good but I was here about 30 minutes.






All transmissions done with 25W. Except 60m were 15W is the legal limit. Antenna still is the coppertape multiband vertical at 9m agl.

Sunday, October 22, 2017

New homemade digimode interface

I've had it with digimode interfaces that don't work or that only work sometimes or under some circumstances. The new JTDX and WSJT-X software requires a variable audio input as the audio input slider has been removed. Sometimes the audio slider in the computer software just isn't working well like in my old laptop.  I've been searching for a commercial one, but if you want something with variable input/output they are not cheap.

So I decided to make another modem, a very simple one that use the VOX in the FT817 for TX switching. I'm not the first to try that and there is even a modification for the FT817 to activate the VOX on the backside mini DIN connector which is originally not functioning with VOX, only on the mike input. That mod can be done but you need to remove the complete "motherboard" of the FT817 and I find that too risky. So I use the mini DIN connection for receive and the RJ45 mike input for transmit, this has been done before by others. Just to be shure I would have a clean signal I completely isolated the computer/radio with 1:1 audio transformers and I use small caps to ground to completely remove any RF. To couple the audio I place 2 electrolitic caps in in and output to block any DC. Things should be good that way I thought. Well, it did work when completely on batteries.

But when I connected the laptop power supply the radio goes in constant TX till I switch off the VOX. I really didn't know why in the first place but it then occured to me I forgot to connect ground connections together on both sides. After I soldered some extra wires the problem seems to be solved in the first place, at least on my base antenna. However, I still have issues with the magnetic loop connected. So I changed the RG58 coax into Aircell7. I don't trust RG58 at all and had a lot of problems with it in the past, but this time it didn't solve the problem.  Monitoring with my IC-706 let me know that as soon as I touch the power supply connector VOX jumps in and radio transmits even without connecting the laptop to the power supply!!! And when I plug the connector in the laptop I get a very large hum on my audio. It was obviously a power supply problem and solved it by a extra "line filter" made from a large ferrite clamp.

After playing with it a while I didn't like the TX volume control, it seems te laptop does have a large output volume and to get a good ALC reading I need at least a very low output volume to actually control it with the potmeter, So I ad a 100K potmeter in series with the 20K potmeter inside to have better control over it.

Below the diagram of the interface if anyone likes to replicate it. Everything is made from scrap parts. I used a housing from a previous interface project, DIN connector with wire from a mouse, RJ45 connector with wire from a old network cable, Jack plugs found in my electronic garbage box, potmeters, knobs and capacitors from a broken CB radio.

I tested on the vertical with WSPR on 20m last sunday and results are promising. However, the main test would be with the loop antenna inside the house or garage or anywhere  I want and on battery power as all this is for portable use. Today (a week later!) I had the opportunity to test it again on 20m and with the magnetic loop in a corner of my shack. The results for a few hours in the afternoon:

I was only received in Spain and Italy but I think a RTTY contest was disturbing 20m WSPR receive. However my receive did very well!

The setup: My old laptop with WSJT-X. FT817 with on top my new audio interface and the ZLP electronics CAT modem so I can control the radio with the computer. It works well like this. I tried FT8 on 30m but my computer is just too slow for it. However it looks like FT8 is a better propagation indicator compared to WSPR these days! So unfortunate JT65/JT9 is not as populair as before.

While testing my magloop I was on FT8 with my base station and found the 12m band wide open.

Before attending the 12m band I was looking at 6m and 10m. I threw out a few CQs but nothing came back. However, I was received in Reunion Isl. as you can see on the map (pink spot).

Wednesday, October 18, 2017

30m band magnetic loop test with the W5OLF WSPR VCXO-AXE

I almost forget about the small transmitter I have and built in 2015. The right transmitter to test my magnetic loop in practice. And while setting it up it seems it leads to a solution for a tuning indicator I was writing about before. What about the simple field strength meter I built in 2014?

Well, you see how it is positioned. But I have room enough in the box to build one in! I still have a old SWR meter as a donor for parts. Why didn't I have this idea earlier? It's so simple and it works great.

At first I thought something went wrong as only 2 spots were collected last night. But this evening checking the WSPR watch app on my iphone it seems my 1 watt signal is spotted at least in a 900km radius.

I'm running the transmitter on a small 12V battery and actually don't know if it has enough power. The W5OLF WSPR transmitter only does 1W at 10V which is only provided by the voltage regulator when the battery is fully charged. Another idea I have now is to build in a small digital voltage meter like in my homemade power suplly so I can check the battery, there is room for it but of course it will take some extra current from the battery. Thinking about that.

Amateurradio is fun!

Tuesday, October 17, 2017

Create RC5-3 rotor overhaul (2)

Well, the first post about the Create rotor did actually have more pictures from the Kenpro in it and I should rename it to Kenpro KR600 overhaul, though it all happened in 2006.  I received the potmeter for the create rotor and installed everything, it does a fine job. However, since the create needs 6 holes to bolt it to the tower and the Kenpro only 4. Not shure what I will use. I might renew the potmeter in the Kenpro as well and use it again. Selling the create will give me some money to buy other hardware I need for the tower.

Monday, October 16, 2017

Beautiful autumn weather

Sorry for those in Ireland experiencing bad weather and large winds. In the Netherlands we have some of the best sunny days of the year. Temperature about 20 degrees celcius. Influenced by some of PC4T Paul's videos I made one of our garden...enjoy!

For those that say it has nothing to do with hamradio....well a secret shot related to radio is included...
Curious who spots it?

Thursday, October 12, 2017

Failed projects and experiments

If you read most of the blogs about amateur radio it's always about successful projects and experiments. I don't believe that every experiment can be successfull, or I might be the only experimenter that is most of the time unsuccessfull. I can't tell you the numerous times I setup a antenna and it didn't work at all. Electronics that don't work. Software or hardware that isn't capable of something you need for a experiment. Failing test equipment and failing equipment. I always have many ideas but most of the time it just is in my mind and sometimes things are impossible or is just too pricey. Most important is that you don't give up! In the end you will succeed or come up with another solution for the same challenge. Since a failed project is not a problem but a challenge!

Some of the projects that (partly) failed:

Well, I'm a believer of making things. But sometimes you really get crazy when you spend a lot of time on a project and it isn't working the way you want. Remember my USBlink digital modes modem? When I saw G4ILO made one I made my own design in 2010, it wasn't working at all. After some quetions in a hamradio forum we finally found the fault a year later. I finally used this modem for the first time in Denmark this year and it functioned without any problems. Back home I want to make a setup battery powered and portable. The modem functioned on PSK with FLdigi but doesn't TX with WSJT-X on JT65/JT9/FT8/WSPR. Strange? After some tests it seems it doesn't work when the radio is not on a power supply. It has nothing to do with low voltage, even a external 12V battery doesn't solve the problem. Till now I can't find why this occurs so probabely go for another solution, building another interface.

In 2012 I wanted to make a simple endfed that would be reproducable with simple hardware that everyone could get at any DIY store. However the theory and experiments you find on the internet didn't work for me. I did a experiment and in the end I had a working antenna but it wasn't as simple as I thought. For me this was actually a unsuccessful experiment but I learned a lot from it. Not that I plan to make another endfed as PE1BVQ Hans made a well working 3 band endfed for me that served me well on several /P activations.

The radio shack ground myth. Well I made something working I thought. I made a lot of effort to study RF ground but it still is a pitfall. I think the system I use is working well though I have to choose between safety earth and RF ground with a switch. When I had problems with interference on my VDSL modem things got worse when I used the safety earth (switch closed, earth from radio equipment to earth electrode). When I opened the switch and used just the counterpoise it was a little better (but still there). So, the switch thing is not really a need after all. Is it a failed experiment, not really but my thinking was just wrong. You don't really need a earth at your equipment and if so you could try a counterpoise. I added a 1:1 balun just after the tuner to the vertical and added a ferrite ring between earth from main earth point at the powersupply to the counterpoise. Might be I'm thinking wrong again but in practice it works for me. This way the counterpoise is probabely not working but it doesn't harm as well.

Last year I experimented with a S-Match antenna tuner setup after I purchased a homemade QRO endfed tuner. But things went wrong and I blew the MFJ-259 analyzer. A classic example of failing equipment. And it was my own fault. However I was impressed the S-Match still got a 1:1 SWR with just a meter of ladderline on 30m. Did some experiments after this disaster and it was successful but need to do some more experiments to get what I want.

In 2014 I played electronics engineer. Shouldn't do that, not really capable of it. I destroyed the TX/RX relay with my big soldering iron and blew the finals. Never wrote about that, it was my own stupid fault. At that moment I had it with electronics and sent the amp to PE1BVQ Hans to play with it. However he repaired the thing and gave it back. So a big thanks to him although I never had the intention to play QRO. It might be interesting for a portable experiment in the future.

Tuesday, October 10, 2017

Create RC5-3 rotor overhaul

This rotor is one of the "left overs" from Foppe PD0FF's equipment. I couldn't sell it as the rotor is broken. I remember Foppe already had problems with it but when I dismantled his antenna back in 2015 the rotor still turned. Now my goal of setting up the new antennamast is coming close it is time to see what hardware needs to go on the tower. And since I'm out of hobby money I need to repair what I have in stock. Well, in 2006 I repaired the Kenpro KR600 which was originally bought together with the tower. However the Kenpro is more complicated and needs a overhaul as well. Besides that I like the controller box from Create a lot more. The Create RC5-3 is a very simple design with a worm gear and with the controller box you can adjust speed and program any direction in which you want to turn your antenna. Anyway I dismantled the rotor and concluded that the lubrication maintenance had been a long long time ago. The 5 Kohm potmeter that sends the direction the the controller was completely corroded and couldn't be turned, the big gearwheel and the smaller one at the left were turning but very heavy and both axles were corroded. The only thing that was lubricated well was the wormwheel. So, I took everything apart and cleaned and grinded the axles and gearwheels. Now I'm waiting for a replacement 5 KOhm potmeter which I ordered in Germany. More photos to follow.

I found some photos from the Kenpro KR600 overhaul in 2006, that one had a broken gearwheel axle which I had replaced but after all there is a problem with the potmeter as well, so far it did reasonable with a small dip here and there but it should really be replaced. I probabely look after that after the Create is ready.

Sunday, October 1, 2017

#FT8 40m & 20m today

I knew KY6R would be on air with FT8 for the first time sunday morning. But had no time to be on physically in the shack. So I left my station listening 40m saturday till sunday night and early in the morning switched to 20m to listen over the day. This are the results:



No sign from KY6R but I did receive stations near his QTH. At the moment I think to check propagation FT8 is the mode to go. It is incredible how many are active on 20 and 40m at any time of the day. 

With the help of JTAlert-X you can view the activity on JT65/JT9 and FT8

I viewed it a couple of times yesterday and today and noticed that there are always at least twice as many on FT8 compared to JT65. And JT9....seems to be abandoned.

FT8 might not be as sensitive as JT65 and JT9 but it is fast and it seems that is what attracts most people. Since we live in a age were time is occupied by so many inputs and things around us it is exactly what most people need to continue their hobby. At least it seems so...