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You might be an HF operator if…

You might be an HF operator if your youngest son (4 y 4 m) mocks your new antenna for 6m by saying: “Ha ha ha what a small antenna that is”.

Indeed, between the HF antennas it looks a bit tiny. I might be looking for something new to do in ham radio. New but then again not radically new. No DMR chitchatting, no EME no PSK. I have never been very active above 28 MHz, as the right column indicates:

I once made an antenna for six meter: The Hentenna. I also found out that a WARC triband antenna has a low SWR on 50 MHz. Both my triband fan-dipole as well as the ‘permanent WARC antenna’. Does not work in any way but it accepts power and doesn’t make the rig or amp unhappy…

I also bought a two element yagi three years ago. What was I thinking? Even that little thing is too big and heavy except to put it on the main tower, which I refuse to do.

Recently there were many 50 MHz spots, so I it was time again to try something there. This time I made a 5/8 wave vertical. Yes with a matching coil. Yes with radials. Yes I tried the new AA-54 antenna analyzer. But it wasn’t easy to make it work by trial and error and I really have too much work and too little time to dig into literature and keep trying. The small support I use for my SO2R triband vertical was still free after field day so I decided to use the unused yagi parts and make it into a simple dipole. I have to start somewhere and my start on HF was with a dipole too.

I have made many dipoles, from 160 up to 144 MHz. It is the simplest antenna and almost always works. A dipole is very easy to get resonating and can be fed with 50 ohm coax. Catch: this 6m yagi uses a gamma match and doesn’t have a split driven element. My first thought was to use it ‘as is’. But the analyzer showed it was not resonating where I wanted it and the huge amounts of possible combinations of element length and position of the gamma match scared me. The easy way out would be to cut the tube in half and make a split element feed point with no matching. The road that has always led me to successful dipole construction. Problem: I didn’t have fitting material for the center isolator and I didn’t have access to a lathe to have someone turn it down to the right size.

My garage roof is Antenna Parts Walhalla, with many unused and decommissioned antenna parts. One of these parts is the mounting bracket for the 10m three element yagi. I did a remake of that antenna somewhere late 2011 when the cycle began its peak and 28 MHz was wide open. I had wild dreams of putting up a second beam for 28 MHz, doing power-split in two directions etc. The problem is that I never had the proper support to do that. I now have. And maybe a second and more permanent option in a while…

It was time for some affirmative action. I coldheartedly cut the tube in half. Since the elements are not long thus not really heavy, the four clamps (two on either side of the dipole half) provide enough clamping force. Just to be sure I hastily cut a small strip of insulator to provide some extra stability.

Mathematics and measurement were on my side. The calculated half wave length for 50.2 MHz and the measured length of the dipole were the same. I had some excess centimeters should tuning and pruning be needed. I had a piece of coiled up coax in my parts-bin with the shield and center conductor split and with cable eyelets on it so I took that to hook it up to the feedline. I think it’s a salvaged part of the hentenna. With the dipole about six meters high, the analyzer revealed that this antenna was good to go. SWR dip nicely around the part of the band I’m interested in. I hooked it up and went into the shack.

I didn’t hear much. Antenna not really working or just a case of Tragic Band? I called CQ with 500W output and watched the RBN. I wasn’t getting into the skimmers, that much was clear. There were a few question marks thrown at me. The signal had that distinct ‘local sound’. Sure enough it was an ON4. He put me on the cluster after the QSO but no one else called me so I called it a day.

The day after. A few spots again but I couldn’t hear much. I only heard ZA/HA2SG which after logging him, might be a new DXCC on 6m. Later on there was EI4KF calling someone without success. So I asked ‘EI4 PSE UP 1’ and went CQ’ing there. I logged EI4KF who was S7 for what I believe is another new entity on 50 MHz. There was a German skimmer picking me up pretty loud but no one else answered me. I tried again three times later that afternoon and evening but never did I get a reply and never did a skimmer pick me up seriously.

I admit that a dipole is not much. I agree that it might be too low. But is it really the antenna that is bogus or is it just that whenever I tried, the band wasn’t productive here?

I didn’t bother to take pictures when I made the antenna on Wednesday. I’d do that the day after. I wanted to get on the air ASAP. Only it started raining yesterday and it’s raining again now on Friday so… No pictures for now. Hey it’s just a piece of aluminum in the air. Too small and too low perhaps?

One reply on “You might be an HF operator if…”

6m is a strange band. One moment you hear nothing, the other moment signals are booming. You can have propagation when a station 10km away does not hear anything, propagation can be very local. 2 years ago I made my only transatalantic QSO (Puerto Rico) with only 5W and my W2000 vertical (6m height) using JT65 on 6m. My most memorable contact on that band. Good luck chasing DX on the magic band. 73, Bas

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