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25th July 2020: VHF FM long distance SOTA

Hello,

last July 2019 we did a special event, activating simultaneously from many different summits on VHF FM trying to reach a long distance S2S or chase.

Again this year many SOTA operators want to run this especial event by activating from summits well spaced between them.

The scheduled date is Saturday 25th July, planning to be active around 9:00 utc.

If you are interested to join this event and activate, or if you wish to chase us from a high point at your convenience we can agree and try for a qso; just drop me an email to add you in the list (my mail correct at QRZ.com ).

It would be great to count with CT, F and G activators.

I’ll publish further info with summits list and frequency details in the coming weeks.
Any comments welcome.

73 de Ignacio

P.s. results from last year here, as well as a video report:

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Go, Go, Go!

Hi Ignacio,

Great video editing…

Seeing this video again, I now recognise both you and Juan Carlos EA1AER, who participated in the event last year.

I notice several stations used horizontally polarised antennas but most were using short yagis oriented for vertical.

Every time we in VK1 try S2S contacts with HTs and beams or vertical antennas, we find that horizontal antennas give us better dx. I recommend you try that this year, I would love to know whether it works for you too.

I suggest start with a vertical polarised antennas and whatever the outcome, go horizontal and see if the signals are any different. If radio waves work in EA the same as they do in VK, you should get better signals using horizontal polarisation (even with an HT held so the antenna is horizontal).

I could hypothesise about what makes the horizontal polarisation work better, but as I can’t really back up my ideas with proof, I’ll be content with the empirical (experimental) evidence.

73 Andrew VK1DA/VK2UH

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Something to do with the longer V/UHF paths requiring a bit of diffraction over the top of the terrain to make the distance, and that diffraction favouring horizontally polarised radiation, perhaps?

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Hi Andrew,
thanks for the comments. Yes, things work the same here in EA than in VK :grin:

Last year, we focused on Vertical polarization in this event just to make it it easier for most chasers around us who had vertical antennas on their roofs.
I agree horizontal would favour longer distances but then we would lose contacts with these people who don’t have a yagi at home…

The activators who have a yagi hold by hand can turn instantly and check the effect, but for those fixing them on top of their poles we discussed and finally agreed on putting them vertically oriented for the above reason. Some others could play and check about signal variation with polarization.

Let’s see what we can do on the event this year. Myself, I can recall of being able to complete a qso when tilting my handheld parallel to ground; it depends on conditions between both ops.

As in the last year, we’ll publish the results of our experiment this time here in the reflector. Pity we can’t convert it into a transcontinental event, hi!

73 de Ignacio

4 Likes

hi Ignacio,
I think the experiment could take place if comparison of V and H polarisation is included in the mission goals! while most operators won’t take both polarisations, especially for FM where the presumption is that some stations are using vertical home antennas, or are using vertical field antennas to be able to work those vertical home stations, more operators will equip for both polarisations if they are interested in the experiment. Just knowing others may wish to test the polarisation change will help get more on board.

One method of tilting a beam between H and V is to mount a beam on a camera tripod that is designed to tilt a camera between H and V (landscape and portrait mode). Using that tilt mechanism is a neat way to quickly tilt a beam by 90 degrees at both ends of an S2S path. that assumes a tripod is used to mount the antenna, that is desirable anyway as it removes the operator’s body from the immediate antenna field.

Anyway you know all this, I”m only writing it to try to attract attention of other operators!

Just last Thursday I had another experience of making a scratchy FM signal become fully quieting, by changing from vertical to a horizontal antenna at both ends of the path.

73 Andrew VK1DA/VK2UH

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In the UK when UHF Band IV/V was chosen for TV, horizontal polarisation was chosen as tests showed it gave the best signal in the desired coverage areas for the main stations. Even for somewhere as small and densely populated as the UK, getting full overage for UHF broadcast TV was going to be a massive investment so anything that maximised return was welcome. Relay stations were designed to fill in the gaps. Planning frequency choice to enable 4 channels from each main or relay without mutual interference and with interference into Southern Ireland, France/Holland//Belgium was challenging. So main stations used HP and relays received the signal off-air from a main station (typically using a trough or pair of trough antennas and space diversity) and rebroadcast on a different set of frequencies using vertical polarisation. Maximum coverage from relays was not a design goal. With digital distribution and GPS derived sync, synchronous networks of DVB and DAB are possible.

Band II FM broadcasting was also originally (1950’s) designed for horizontal polarisation for best coverage. In the 50’s the standard was 8 tiers of 4 skeleton slots that also formed part of the antenna tower structure. By the late 70’s VHF FM car radios were becoming affordable and the network was modified for mixed polarisation, horizontal for best DX and some vertical component for car/portables using short whips. This involved new towers for many sites as removing the old skeleton slots robbed the towers of the ability to support new antennas. Some sites use panels of 4 HW dipoles (2 horizontal 2vertical) with the ability to support RHCP, LHCP, or mixed H and V. Or A. Dick & Co. spearheads or Sira(Kathrein) mixed polarity dipoles. Relays tend to have slanted dipoles or simple vertical dipoles.

I think it’s well proven from nearly 70 years of VHF and up broadcasting that horizontal is best where you are receiving either a direct signal or possibly diffracted. Once you get to incoherent tropo scatter then it matters less. But as mounting big horizontal Yagis is much easier than big vertical Yagis, horizontal is still the way to go.

Hello,

we are approachiing our event. So far we have a lot of activations planned from many different SOTA in EA and one from France (thanks F6HBI !!).

We keep our fingers crossed so that weather is fine this day and a bit of Tropo would be of help.

Anyone interested on chasing VHF from the neighbor countries?

73 de Ignacio and all VHF ops participating.

1 Like

Hello,

after some weeks working to allocate all teams and provide a big coverage, a lot of people agreed on participating this Saturday 25th.

To date, there will be 22 active summits on VHF FM this Saturday (maybe some more will add next days…).

These are the SOTA summits planned:

We keep our fingers closed to have good weather and propagation for this event.

Would you like to chase them? Bear in mind the propagation enhanced by the sea shore.
Try to hear them between in the range 145.200 up to 145.575 MHz in 25 KHz steps.

We will be up there waiting for your calls.
As we did last year, we will publish a deep report afterwards.

73 de Ignacio and the rest of the crew.

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Some hours left for our event and… 24 summits will be active tomorrow on VHF!

Has there ever been such a crowded VHF event before for SOTA?

Cross the fingers to chase a lot of them S2S.
I’ll write report in the next days.

73 Ignacio

1 Like

No 2m FM SOTA DX heard here yet. Keeping myself entertained on other modes on the band meanwhile…

I hope the weekend picks up as the skip is terrible I can’t even get any of your signals Tom on the data modes and trying to get Spain just sounds like a farmyard full of chickens.
Oh well moan over lol
73 all

I’m a chaser and was interested by this event …
Too much different frequencies to monitoring X different heading !
Maybe wasn’t for me, I’m closed to Mediterranean sea (only 60m ASL) but nothing til 100km :expressionless:
I hope a success for this second try but for me an Excel sheet with all previous station and they own freq displayed will be an good tool :slightly_smiling_face:
It’s interesting challenge but very hard !

Tom activating every day G/SP- :thought_balloon: and :gun: don’t have this problem he can got, all time, in VHF his SOTA quota :slight_smile:
By the way : Happy birthday Tom !

73 Éric

1 Like

Congrats to Ignacio EA2BD for the successful event he has organised.
>Felicitaciones a Ignacio EA2BD por el exitoso evento que ha organizado.

I wasn’t sure of being able to participate until the very last minute, when I saw a small time window for me to drive up to Mt. Erreniega EA2/NV-092 and make a brief activation.
We had a perfect blue sky today and the temperature was nicely warm in the beginning and hot with a hammering Sun later as the time passed by.
>No estaba seguro de poder participar hasta el último minuto, cuando vi una pequeña franja de tiempo para conducir hasta lo alto del monte Erreniega EA2/NV-092 y hacer una breve activación. Tuvimos un cielo azul perfecto hoy y la temperatura era agradablemente templada al principio y calurosa con un sol machacante más tarde según pasaba el tiempo.

This is the view towards the East:
>Esta es la vista hacia el Este:
imagen
I carried and set up with a home made 75 Ohm coax cable colinear antenna and also a Diamond dual band mobile antenna with a single 1/4 wave wire radial.
The rig was my trusty FT-817ND working today through the BNC antenna socket at the front for a change.
>Llevé y monté una antena colineal de cable coaxial de 75 Ohm que hice yo mismo y también una antena Diamond bibanda de móvil con un radial de 1/4 de onda.
El equipo fue mi leal FT-817ND trabajando hoy por el conector BNC de antena en el frontal, para variar.

The first 5 QSOs were made with the coax cable colinear, which was giving me a bit high SWR but not terrible. Then I changed to the mobile Diamond antenna, which I had setup on top of a PVC tube held vertical with the help of a tripod.
>Los primeros 5 QSOs fueron hechos con la colineal de cable coaxial, que estaba dándome un poco alta ROE pero nada terrible. Entonces ambié a la antena Diamond de móvil, que había montado en lo alto de un tubo de PVC mantenido en vertical con ayuda de un trípode

This is my log with 15 QSO, 5 of which S2S:
>Este es mi log con 15 QSOs, 5 de los cuales SaS:


You can see it on the map:
>Pueden verlo en el mapa:

It was a fun activation and it was nice chatting with some well known EA2 activators.
It was particularly nice having a face to face QSO with Luis EA2DPZ/P, who came up to see me at the summit and with whom I had a 2m FM QSO when he was still out of the AZ trying to find me. We had been good ham friends about 25-30 years ago but life took us appart and we had not seen each other since then. It was a great reencountering and I look forward to more face to face QSOs with him, as well as on the air.
>Fue una activación divertida y fue bonito charlar con algunos bien conocidos activadores de EA2. Fue especialmente agradable mantener un QSO cara a cara con Luis EA2DPZ/P, quien vino a verme a la cima y con quien tuve un QSO en 2m FM cuando estaba todavía fuera de la zona de activación tratando de encontrarme. Habíamos sido buenos amigos de radio hace unos 25-30 años, pero la vida nos separó y no nos habíamos visto desde entonces. Fue un gran reencuentro y espero más QSOs cara a cara con él, así como en el aire.
imagen
Thanks dear chasers and activators for being there and making QSO with me.
>Gracias estimados cazadores y activadores por estar ahí y hacer QSO conmigo.

73,

Guru

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1 Like

Hello,

I am still far away from home with limited access to Internet, but just want to send a brief note to say the event was a complete success!!

In the end there were around 30 SOTA summits activated that morning on VHF FM and many people participated chasing us either from home or even portable from certain high areas.

That made the activation a joy. I worked 60 stations that morning from EA1/LR-001 and logged about 17 S2S, incredible for being VHF!

Thanks a lot to all participants. Many people has refused using VHF in the last years, but this event showed that a lot of fun is possible with very simple equipment and antennas if we organise and are QRV on the band.

As stated, it will take some time to collect all logs, and to calculate distances, etc, but we will publish some results and conclusion later on.

Again, thanks all for making this day so special. An activation that I will remember. Many people expressed thanks and is considering to get more involved in SOTA from now on.

73 de Ignacio

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