Dipole for 20m

I have been making use of Instagram for a while because it allows for fast publishing of BS and images.

Lately I haven’t got much to say that is blog worthy. After all these years you cannot keep on telling the same things about the same contests.

Here is a collection of things I posted about the 20m dipole on my portable field day mast made of tubular tower and a base with a winch mounted on it. I made a tapered aluminum 20m dipole which is a beauty but too heavy for my mast. This mast was designed to haul up some wire antennas for field day, not to carry heavy aluminum antennas. Let alone a rotator.

In the end I decided it was too risky to put this in the air even without any wind. I made up an ad-hoc wire dipole on two cheap lightweight fishing poles I have here for almost ten years. This worked just fine on a mechanical level and proved a winner RF-wise to fill the gap when the beam was to USA. It was oriented with the antenna lobes radiating to Japan and SW-EU.


Making the coax choke


Attaching to the mast


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The center assembly for the 20m dipole is ready: feed point and bracket to attach to the portable field day mast. Starting diameter is 40mm. A bit overkill for a 20m band element (~10m long) but the center isolator was made for this and I don’t have access to a lathe right now to turn it down. Adapt, improvise, overcome. Maybe I’ll use agressive tapering to get to a smaller diameter fast. I’ve never put anything this big in my /P mast. Only wires. I hope it’ll work. Build first, worry later! ________________________________________________ #hamradio #amateurradio #diyhamradio #hamradioantennas #antennaporn #dipoleantenna #homebrewantenna

Een bericht gedeeld door Franki – ON5ZO – OQ5M (@on5zo) op


The mast partially assembled


Aluminum version too heavy


Lightweight wire version is up!




IARU HF Championship 2020: OPØHQ 20 CW

I did not participate in 2019 but this year I wanted some piece of the action cake again. A huge slice (20 CW) or nothing. As a one man show of course. I’m not someone who shares the little fun that one band offers in just 24 hours.

Two years ago  (link)  I managed to stay out of the remote network. As the only station out of twelve. I am not a huge fan, it doesn’t help me to make a QSO extra and it opens up Pandora’s box for software problems or freezing logger software. I attended a pre-COVID meeting early February, during one of those stormy weekends. We were still joking about the virus then. Little did we know.

I felt kinda pushed into the remote network thing during that meeting. One of the UBA officials made it more or less clear that it was mandatory for everyone. Fair enough so at one point I said I would step back if that was the case. With no hard feelings. And I meant it. Rather do Single Op than do something I don’t like. And I would not hold that against anyone. That strong is my feeling against all those gimmicks that don’t really lead up to extra on the air performance. And for those who don’t know me: if you try to twist my arm… I find ‘Prinzipienreiter’ such a beautiful word.

Another UBA official said that two years ago I made a lot of QSO (i.e. more than anyone else) and that finding a valuable replacement would not be easy. True ☺. Someone else at the table tried to ensure me that this network thing is completely transparent and does not cause latency or did not cause any problems with the logging software. So in the end I agreed to give it a try and make everyone happy. But with a lot of doubts and prejudice.

Just like in 2018 I wanted an extra antenna to fill the gap to EU when running USA. I used a wire dipole as an almost flat top antenna, stackmatched with the yagi. It felt it was a good addition. This year I made a full size aluminum dipole. Very successful project, but too heavy for my field day mast (link). I could crank the tower up but it felt unsafe. Since my garden is not that big I tried to leave it unguyed. The antenna analyzer showed a nice SWR curve but it is simply too heavy. All that 36 hours before the contest. All that work for nothing. Even worse: I now need to stock a full size 20m dipole.

On Friday I settled for plan B: two lightweight and cheap fishing poles and copper wire. The field day mast was installed anyway. Might as well use it instead of the fiber glass poles I used two years ago. I hauled the portable tower up and SWR was flat along the 20m band. The fishing poles are only 4m long. I left the excess wire hanging loose towards the ground. This dipole was now about 12m above the ground or 0.6 λ. It was fixed with the lobe to Japan and France/Spain and CN. I connected the rig straight to the stackmatch. Nothing in between. I did some RX testing and it worked just fine. The yagi and the dipole have about the same impedance R+Xj, which means the A+B transformer makes it back to 50Ω. I could use the amp settings for all three options (A or A+B or B). So I would not have to touch the amp. Friday afternoon, all set to go.

I will be short about the contest. All things went great. Even the network. Rate was good, DX was good but the band did close for a few hours. I decided to take nap, because calling CQ in vain is tiresome and I wanted to be fit when the band opened up again. I was QRV around 5AM local time, which is 0300z. But the band was still closed. Apart from some big gun Russians which were of course worked on Saturday. I had set myself the goal of 2000 QSO but I fell short two dozen claimed QSO. I think that this is about as good as it gets with one small tribander (short boom) only 1 λ high. Numbers on 3830 confirm this.

The dipole was a great addition. The footprint on the RBN confirmed this. I think I ran with both antennas combined about 90% of the time. I’ll try to put something down about this antenna. On a few occasions, with the yagi to USA, I tried the difference when a JA called in. Almost unheard on the yagi (90° out of the direction), solid S7 or more on just the dipole…

Once again a very enjoyable contest operation!



CQ WPX CW 2020

I didn’t do much on-the-air radio in May. I got some antenna work done to get a second antenna on 15/20m again for SO2R. In anticipation of this contest.


I wondered how I would do compared to the SSB part a month ago. I landed just over 4 million points just shy of 2000 QSO. I targeted 3000 QSO in the CW part, just to prove that CW beats SSB any day.

The day before the contest, I installed some extra antennas:

I had a slow start. A  *V.E.R.Y.* slow start. The 40m band was full. I wanted to run bout found no place to park. I got on 7061 and then started a slow run with some 80m QSO on the second radio. The first hour went by with just passing the psychological barrier of 100 Q: 103 contacts is a slow start. Luckily I could keep this up for a few hours. The 80m was just OK. After sunrise I went to 28 MHz right away because that band was whopping. I scraped 9 contacts from the noise floor last month in SSB. I easily logged more than hundred early in the morning. That’s probably more than what I logged on 10 meters in all the contests of the three past years combined. This sun takes but it gave some this weekend too. I admit: it was mostly EU but it’s TEN and there were tons of prefixes. After that I had a good run on 15m too. Same feeling: 79 hard fought contacts in SSB and an easy +100 run this time. Thanks to the sun. Saturday afternoon I attacked the 20m band yielding the best hour of the contest: 130 Q/hr. That is not really a lot but it is what it is. I stayed on 14 MHz until late in the evening. I was surprised that the band was open this late supporting DX propagation. After that I went to 160m. This is not an important band in the WPX contest but the ‘fresh meat’ experience boosts the rate and there are some prefixed there that can’t be found elsewhere because of the SB160 guys. I didn’t stay long and spent the rest of the second night on 40m. That band gave rate, prefixes and 6-point contacts. What more can you ask for?

During the first part of the contest the K index had risen to 3. That was felt in the propagation! Typical situation: low K and good conditions the weak leading up to the contest. Right at the start the sun spits some garbage towards Earth that affects propagation. The ionosphere recovered slowly during the contest which was felt too later on Sunday. The sun gives, the sun takes…

I took the last long break on Sunday morning. The plan was to do the last twelve hours of the contest in one stretch. Extrapolation told me that 3000 QSO was possible if nothing went wrong. In the mean time I looked up the Belgian record for this contest in my category: 6.9 million points.

Set in 2002 (lots of sunspots) by DL2CC (German!) from the ON4UN station (big antennas). Beating this score was not really impossible but I would have to go after it with only ten hours to go. Challenge accepted!

A couple of decent runs on 10m and 15m followed. The decreasing K-index had some surprises in store: a few stations from California on 15m. Never expected: East coast was troublesome in the recent past, West Coast virtually impossible. And KH6TU heard me and we exchanged numbers. Booyaa! All this boosted the score and the 7 million mark was in reach. I had to build a good margin for the record to stand after log checking… That margin came in the form of a sustained 20m run to the USA. Finally some action! Three point contacts and a wealthy dose of new prefixes.

To finish the contest I sat on 40m for the double points. I grabbed a few stations on 160m and 80m with the second radio but decided not to spend more time there.

When the closing bell rang I was quite happy with a new claimed Belgian record. Especially since this had been set with BIG antennas way higher than mine (see it here), in a year when the solar cycle facilitated DX propagation. I have a small tribander, ineffective low band wires and only one small tower. Not to mention SFI=70 at best…

I had good fun on the radio in my preferred mode and heard lots of friends from all over the globe.

To John AE5X: your signal was just fine but each S7 DX signal is sandwiched between S9++ local signals here… Good to hear you!



April at ON5ZO

It’s been almost seven weeks since the Corona / COVID-19 confinement. Apart from nature walks with family and dog, and some gardening, there is not much left to do but ham radio. You won’t be hearing any complaints from me about that. Here’s an image from one of the long walks:


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be like: But I would walk 500 miles And I would walk 500 more Just to be the man who walks a thousand miles To fall down at your door #wandelenmetdehond #coronawandeling #komuituwkot #coronawalk

Een bericht gedeeld door Franki – ON5ZO – OQ5M (@on5zo) op

So what did I do?

The red thread running through this month is that I left up the tower and low band antennas after RDXC and WPX SSB. Since I am at home all the time (Corona confinement!) and WX is not too windy… Actually the wind was strong enough on two occasions. Not a storm but très gusty. Everything held up. With the antenna up and nowhere to go, I participated in some events I usually skip.

I participated in a local 6m contest. But I have no 6m antenna. So for that I hung up the WARC dipole. It exhibits reasonable SWR on 50 MHz. Any antenna beats no antenna so I logged 13 CW and 25 SSB QSO. Of which one DX: a DL.

I worked 51 Japanese stations in their JIDX CW. All on 20m, none of them loud. Some pretty weak and marginal.

Gagarin Memorial Cup. That was fun. I logged 516 CW QSO on 40m only. Lots of stations to work. Confinement is a bliss for our hobby.

Manchester  Mineira a/k/a CQMM. My plan was to work a dozen Brazilians on 15m. That turned out quite… well:

  Band     QSOs    
   3,5      99
     7     357
    14     391
    21      22
 Total     869

A lot of people to work from all over the world. Again: confinement is boosting on the air activity.

During the week there was stuff to work. World Amateur Radio Day SES stations (***WARD). Especially the Spanish: AM*WARD. Spain is not always easy from here but I think I’m up to 30 now.

Never waste a good crisis and any occasion can serve a Special Event Station purpose. STAYHOME, STAYSAFE, HOPE, ANGELS and other variations on the theme. At first I wasn’t really in to this. But then my club opted for OT4HOPE and since I was on the license… I made 1100 QSO so far, mostly CW. Of course.


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Someone is trying to convey a message on the amateur radio frequencies… QSL ABT QTH! #amateurradio #hamradio #qrz #qsl #radioaficionado #specialeventstation #stayhome

Een bericht gedeeld door Franki – ON5ZO – OQ5M (@on5zo) op

Another red thread though all of this is the absolute abysmal conditions on HF. There is DX but it’s few and far between. Openings are short lived and moreover: during weekdays there seems to be no one around even of a band shows signs of life. I’m talking about classic CW and SSB. Don’t care for anything else.

My conclusion: if there is no award to chase or online ‘leaderboard’, people don’t care. And CW contesting during the weekends is currently alive and well, even in small unknown contests.

73 and stay safe – stay home!




This contest is always low priority for me and most of the time I just skip it. It usually comes right after a series of contests (both UBA DX, both ARRL DX and RDXC), it’s only SSB and it usually falls on a weekend that has social commitments. None of this in 2020. I missed all contests in February and early March because of the storms. Social commitments in the Covid-19 era are non-existent. So I let the antennas up in the air after RDXC and decided to play in CQ WW WPX anno 2020.

My initial plan: SB20 with an auxiliary 20m antenna to spray RF in two directions with the stack-match. I had played with this idea in the past and it would be useful in other contests too. So my youngest son and I started building a 20m dipole. Not a wire inverted V but a real flattop dipole. I would use the field day mast to get it up about ten meters high. This plan was a follow up of my 2018 plans and ideas (read here)

I started collecting all parts from the scrap bin. This antenna needn’t be pretty, it needs to work and be ready in a few days. Soon I had to give up. There was one size of aluminum tubing missing to make the tapering and I was missing some bolts of the right size and diameter. This is not a problem under normal circumstances. But now all stores are closed. So I gave up on the antenna. And the SB20 effort. I would just do a SOAB(A) HP entry for fun. No goals, no targets, no stress, no real time scoreboard. Just run a band that is open and when it’s no longer fun: take a break.


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CQ WPX SSB Contest With off the premises activities strictly limited, I suspect -no: fear- my radio shack being invaded by my boys (8 & 10 y/o). With phone activities there can be zero verbal interaction as opposed to telegraphy. So I decided to turn them into SWL. I installed my headphones distribution amplifier and hooked up two extra headphones. I gave a quick lesson on the NATO spelling alphabet and tested for EMC / RFI when running QRO. Seems fine. Look for OQ5M trolling the bands. Just for fun, nothing competitive this time. #cqcontest #hamradio #amateurradio #swl #cqwpx #cqwpxssb #behringer #behringerpowerplay #hamradioshack

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The closer the contest came, the less I was tempted. SSB… Closed upper bands… Phone on 40? Oh boy. I went to bed on Friday and set the alarm for 4AM local time which meant the contest would be in full swing for about three hours when I would finally land in the chair. Not so. I snoozed and snoozed. Then I got up. But I didn’t go into the shack yet. In fact I was looking for excuses not to start. I got a message from K7GK/6 who had a very unproductive period from the SF area. W6 is not z14 but anyway…

I took a late start and decided it would be on 80m. Signals were good even from the USA. A worked quite a few of those: 38 in total. It’s a phone contest and I missed prime time for this band. After about 150 QSO I moved to 40. Ouch – forty on phone. I. Hate. That. Nevertheless I had two hours of about 125 QSO each. Then a three hour break.

Back some 20m and pathetic efforts to work someone on 15m. That’s how I spent Saturday afternoon: slow runs on 20, desperately looking for life on 15. In the evening I did 40 but not much success. I did 160 but that wasn’t a hotspot either. I did work two fast hours on 80 then, about 240 QSO in total. The wee hours of the night were slow and uninteresting. So I took a break for a nap and answering a call from nature. QRX 180…

I knew from my SB80-efforts in CQ WW SSB that 3656 is a good place for both EU and USA. This once again turned out well. Maybe I should keep this to myself? Around 0630utc a local French net claimed the frequency with the usual contest mockery and profanity. It doesn’t always have to be a German invasion or a G-tea party.

By that time I had taken a look in the scoreboard. With my ‘just for fun’ attitude in a phone contest I was way down in the list. Über-nice-guy Anton ON6NL was there (below me) and OR3A way ahead of me. That upset my contest-ego and triggered my competitive drive. Suddenly I went from ‘laid back – no goals’ to ‘not on my watch!’. The target was simple: get over OR3A. It’s nothing personal Marc. You’re a good operator and a very nice guy, I know that. But I have my small sides. This is one of them. The problem was that OR3A had a big deal of score advantage. Furthermore he worked way more 6-pointers on 40 where I focused on 3-pointers on 20. How does he do that? I will ask later on. I don’t think he has a big 40m antenna (but I might be wrong).

During the day it was obvious that everyone is on 20m. There was no free spot to call CQ. If you run barefoot and have a multiband vertical, this SSB contest obviously is not for you. US1Q had an awful signal and he decided the RS report 59 is optional. UB7K was even worse. From here there was more than 7 kHz of spectrum around him that masked everything else below S9. There were many stations not giving the mandatory 59 report, just the serial…

The afternoon was uneventful. Runs on 14 MHz were not spectacular, it was hard to work something on 21 MHz. The good thing is that I caught up with OR3A and by the time the contest was coming to an end, I had a good margin to beat him. Which I did, at least judging from the real time scoreboard.

I had a few good hours and a few boring hours. SSB is hard on the ears and not nearly as much fun as CW. I hope I can do SOAB in the WPX CW in two months.

Support the contest scene!