Sunday, December 16, 2012

ARRL 10 metre contest

I had decided a few months ago already that I wanted to make a serious entry with a view to putting in a good QRP score on SSB, operating portable-style from my usual seaside location.
I’d done a lot of prep work with the 10m antennas, trying out 2 element and 4 element designs, with a 2 element phased design in the works. I had the option to use the FT-1000 MkV Field in order to do SO2V, the poor man’s version of SO2R, CQing on one VFO and doing s+p on the other. So I was quite prepared.
At the beginning of the week prior to the contest, conditions were very poor, but the NOAA forecast was that it would get better, with an SFI forecast of 130 and low absorption. However it just didn’t happen and on Saturday morning, SFI was at a meager 95. Great for low bands, not so hot for high bands....
I trundled on down to the port and set up. In the end I used my Kenwood TS850, since I hadn’t had time to set up the audio on the Field and also it didn’t fit in the car. I set up the quarter wave on the car and the 2 element vertical yagi and had a tune around. Heard JY4NE and called. And called. And called. He finally pulled me out of the noise. No such luck with VK6IR. Or with RT4RO. After an hour, and only one more QSO in the log, I realized that there was no way I was going to get any kind of record on QRP, so I cranked up the wick to 100w. This time I managed to get VK6IR and a couple of others in the log but really not a lot happening.
I decided that since there was nothing happening, it might be a nice idea to try out the new phased design. This is based on the notes in the WX0B stackmatch. Basically it consists of two identical half wave verticals, in my case centre fed. If they are spaced a half wavelength apart, when fed together using a 0.41 wavelength phasing line from the phasebox to each vertical, it will give a broadside pattern with 4dB gain over a single vertical. It can also be fed to give endfire in both directions, with up to 6dB gain with a half wave of spacing. With the centre fed antennas, I used a third fishing rod in the centre to support the box. This meant that I was able to get full spacing (5m between verticals and 2m80 lines means the box cannot be on the ground!) and also keep feedlines quite horizontal to avoid feedline radiation. Unfortunately the clamp was too big and I needed to tape it all up provisionally. This is what it looked like:
How did it work? Well to be honest I noticed very little difference on RX. And there was hardly anyone to test it with on TX. I decided to take it down again and put up the 2 element parasitic I’d started with, on the basis that it was almost less work getting out of the car and moving the reflector every once in a while. This may be a design to think about for a more permanent installation, or for a band where antennas are so big they need to be guyed, or radials need to be moved, etc. But for vertical dipoles on 10 and maybe 15, I think the parasitic design is a better all round solution.
The day wore on and we continued to have what Bob K8IA calls “spotlight propagation”. I would hear one loud Finn, for example, for about 5 minutes, but only one. Then a state might come up out of the noise for a few minutes. Some were even less, the exchange having to be quick and not be left with one of us shouting,….”number?...number?....numberrrrrr?????????????!?!?!” At the end of Saturday, I’d worked all continents, 33 multipliers, but only 53 QSOs!
And that was how it ended. I got up on Sunday and saw the SFI had crept up to 100, but I decided to spend the time doing other things instead. I kept an ear on the radio at home and heard the states coming in at dusk, but in spite of that I think I took the right decision. Next year will be better, right??
Points to note:
 - I might try to recreate the 2 ele phased array using end fed antennas, easier setup which would allow the phase box to sit on the ground.
- End fed antennas also take out the guesswork on whether your feedline is horizontal enough and if its affecting the performance.

- In the afternoon a strong gust of wind blew the reflector down and the SWR went up. I checked, and on the rig it showed resonance at 29.4. I double checked on the analyzer and it showed the same. Something local affecting the SWR? Or did I screw up when I was labeling the elements after putting away the 4 element last time? 
- I plugged in my 12V to 19V DC to DC converter for the netbook and zas! S5 to S9 of QRN. Trying to remember what I used to power the PC last time. And thinking, last time was on 40m, maybe it was making that noise then and I hadn’t noticed? On marginal 10m, you can tune across the band even with S2 noise and think there is no one there. Need to check whether the netbook will charge on 12V straight connection to the battery.

Next contest….um, not sure. ARRL DX for sure, but maybe something in between?

Thursday, December 06, 2012

ZL9HR, finally in the log

Well, I have to admit that I really had my doubts about this one. It's not so much the distance, since in spite of being a long way away (18377km), I still manage to make regular contact with "mainland" New Zealand regularly. It's more to do with the fact that it is a lot further south, 1800km south of Auckland, for example, which makes it a lot more complicated, plus the fact that it's been 13 years since there's been any ham radio activity from there.

The team set out last Monday 26th and was due to arrive a couple of days later. However large storms meant that they had to seek shelter and so were not up and running until Saturday December 1st. This meant that instead of ten days, they would only be there for a week. In spite of having a possible 7 stations on the air simultaneously, the demand for Campbell Island is high and big pileups therefore assured. Also, the NZ department of conservation, in charge of the island, had imposed two conditions that further restricted possibilities. One was that the beach area was off limits, so no low angle verticals on the beach, and secondly, no overnight stays so limited operating times.

Sunday evening I got the news on our HQ whatsapp chat that EA4ZK worked them on 20m SSB. On Monday I heard them on 20 SSB with strong signals, very encouraging, but absolutely no way to crack the pileup. On Tuesday evening a lot of spanish stations took advantage of a brief 20m opening on CW and I am also lucky enough to be in the log.

However what I was really looking for was an SSB contact from the car. Wednesday was a washout, no SSB activity on the long path and then no activity on 40m at nightfall. I went home and checked their web, where there is now enough data to get a good idea of when and where is good to work them. Between that and the spots of the DX cluster, I decided that since today, Thursday, is a national holiday, I had to get up early and take my big 40m antenna with me.

And thats exactly what I did. At around 6.30 I was already setting up the 40m full size vertical and the usual 20m full size vertical on the car, and then sat down to monitor the bands and the cluster. Around 20 minutes later, I started to hear them come up through the noise very weak on 20, and a few calls later 5 kc up, got a call back "mobile??". I gave the call a couple of times, exchanged 59, and gave my thanks for the new one, replied to with a "You're welcome!" I guess the op was Jacques ZL3CW, from the french accent.

Here's what it looked like:

(The spiderpole supports the wire which screws into the hustler mount on the car)

Since I'd gone to the trouble of putting up the 40m antenna, I stayed for a while to see if they would come up, but to no avail. I worked the 5T0SP operators and a couple of stateside stations, and when it was daylight and no real chance of hearing them even if they came on, I called it a day and headed for home.

The crazy things we do for radio.....!