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Ad-hoc day-to-day VHF SSB activations

Like many I mourn the demise of VHF SSB from its heyday and widespread use in the 1970s and 1980s to a minority sport or special events nowadays. Those days will never come again (since most countries have done away with VHF-only licenses) but I’m wondering (Canute like) if it’s possible to slow the decline or even increase its popularity - at least regionally - by a small number of enthusiasts having frequent enough activations that encourages chasers and other activators to join it.

To Tom @M1EYP and others, I’m not talking about VHF special events and contests here (which are great and may encourage a few newbies thinly spread across an association to take it up) but how to increase VHF SSB for yer day-in-day-out ad-hoc SOTA activations.

The spectrum of SOTA activators ranges from modes-bands specialists who ‘camp out’ for ages on a hilltop to get the best conditions through to the keen hillwalkers/summit baggers who don’t want to spend much time playing radio at each summit. I’m wanting to target the middle ground.

I don’t bother taking my (relatively heavy and bulky) FT817 on day-to-day VHF activations when it’s more convenient to take one of my VHF/UHF HTs. But I would do if I thought there was a reasonable prospect of others using SSB – and that means seeing many more VHF SSB alerts.

Here’s where it gets controversial. First, let me remind you “Perfect is the enemy of good”. The SSB purists reading this will say: you have to erect a horizontal Yagi on a big pole to get decent Dx. No doubt that’s largely true but if you insist on that, it will remain a minority / special event sport.

I think we need to make it as convenient to use SSB as FM or DV to attract casual users. So then activators may start on FM and switch to SSB. That means vertical polarization and whips and J-poles (I can hear the purists choking). Yes, of course this won’t be as good as H-polarized Yagis. But maybe, their use will come in time if SSB was more popular. And remember, many shack-based chasers only have verticals (usually colinears) at home.

I’ve read that, all other things being the same, SSB has up to a 10dB advantage over FM (that’s 1-2 S points) meaning a weak SSB signal can still be heard when its FM equivalent has disappeared. So worth trying SSB if it’s merely changing the mode setting.

Anyway, I seek your comments. Would I be wasting my time? Are there any like-minded people in G/LD or neighbouring regions willing to try to get this going in NW England?

regards, Andy

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After having many moderately impressive S2S FM QSOs I’ve long thought that some kind of regular/continuous 2m-with-simple-antenna event was needed to show VHF newbies what is feasible with simple gear. You just did your normal activation and if it was on 2m you could view that separately and differently to how the normal honour rolls show. If you made the activators use SSB on a vertical antenna (J-pole, super rubber duck or beam) then more people who only had vertical antennas at home would be able to see how much better SSB was compared with FM without them suffering the typical cross-polaristion loss of vertical white-stick to small horizontal beam.

The problem is making it appeal to all associations where the hills maybe some distance away from chasers. It would work in parts of the UK but chasers in the SE of England would not hear so much. The same in many parts of Northern Europe. Likewise it would work in places like California where there a plenty of summits overlooking the populated areas. Might not get a big take up in Northern Territories / VK8 though.

It’s easy for it to become a bit of a vanity project for activators in the right places which is why we (MT) didn’t push it.

I like the idea.

The loss when using an antenna with the wrong polarisation is about 20 dB (although in theory much higher!) but an antenna at 45 deg has a loss of 3 dB for both horizontal and vertical antennas at the other end, probably about the same as the loss from using a rubber duck! You get about the same loss from a circular polarised antenna. This is tolerable bearing in mind the mode advantage. Using a half wave mobile whip with an adapter to the 817 however will enable you to angle the rig for best signal.

As it happens, as a chaser I am seriously considering adding vertically polarised beams to my array.

Why an adapter? I used to put my 2m mobile 1/4 wave whip straight onto the SO-239 socket on the back of the FT-817 - worked rather well on 2m and 70cm! A half wave would have been unmanageable because of its size.

(you have to change the selected antenna socket in the menu of course as by default the front mounted BNC was used for VHF/UHF).

As for 2m SSB activity here in Southern Germany - during activity days (e.g. BBT) and contests yes - otherwise it’s dead.
Ed.

Here’s an interesting idea though - a circular polarised Quad!
http://ham-radio.com/k6sti/cpquad.htm

Now that I’m using an FT-817 I am going to add 2m SSB vertical to the list of modes I attempt to use.
Mark. M0NOM.

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The use of slant polarisation has often crossed my mind. I usually start my activations on 2m SSB with the 5 element yagi horizontal. On occasion I have tried vertical polarisation when I have known that chasers with verticals have been looking for me, but to be honest this has been quite rare. I suppose the gain inherent in the antenna has offset the loss due to cross-polarisation to a sufficient degree to facilitate a contact. Perhaps part of the equation is that what leaves the antenna as one polarisation does not necessarily arrive at the other antenna as the same polarisation.

I would certainly be interested in trying a cross-polarised antenna to see whether this increases the number of contacts on 2m SSB. Alternatively a bracket to provide a 45 degree slant might be sufficient to determine whether cross-polarisation is a worthwhile change to the set up.

In my experience, over 14 years of SOTA activating there has been a slow decline in the number of chasers using 2m SSB . Maybe the trend can be reversed if activators are able to find some way to offer both horizontal and vertical polarisation. Time will tell.

73, Gerald

I do have a right angle adapter for the rear socket but find it more convenient to use the front socket with a PL259 - BNC adapter because I have rather thick fingers and that way I can get to the controls more easily. I also have a quarter wave whip with a BNC plug but after comparison I found the half wave mobile whip gave better results, probably much of it due to the lack of a ground plane or counterpoise for the quarter wave, although I think the half wave has a few dB inherent advantage as well. My rucksack is a rather deep extensible intended for rock climbing and the mobile whip goes into it with not too much sticking out at the top. I tried a much longer three band mobile antenna, 6/2/70, but it needed a good counterpoise and stuck up too far when carrying it under trees!

:+1:

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" Perfection is for the Gods . The most we can hope for is excellence." (Carl Jung after Sophocles)

I actually used it with the rig over myshoulder running of it’s internal 1500 maH lipo and the 1/4 wave going straight down - no rt.angle connector. I was surprised how well it worked “upside-down” so to speak.

73 Ed.

I never thought of that, but it makes sense!

My original suggestion was more radical - if we want to encourage a typical VHF-FM activator and the majority of VHF chasers (who are vertically polarized) to try VHF-SSB, we need to make it easy - so no antenna changes from their FM set ups. So, no cross- or circular-polarization, etc required to join in.

Once you have rebuilt a small but active group of VHF-SSB activators/chasers in a given region, that may lead to some of them getting more involved and using Yagis, etc to seek out better Dx. But that’s a secondary aim.

Of course, if a chaser says please rotate your antenna 45 or 90 degrees to suit his polarization, no big deal.

That’s great, Mark. That makes two of us [I feel like Yul Brynner in the Magnificent Seven]. I’ll start packing my Ft817 instead and alerting for 2m SSB too. Maybe others with join us.

Normally I don’t use a radio until I’m at the summit but I’m thinking about trying out a walk-and-talk setup like Phil @G4OBK has, so that I can chat to VHF-SSB chasers and activators on the walk up / down below the AZ.

In my case, I’m going to try re-purposing my Watson WM-627 mobile whip and connecting it to the rear socket of the Ft817 via two PL259-SO239 L-shaped adapters (forming a 180-degree bend) all in the rucksack with a LiPo and with earphones and fist mic coming out. I think the 1.6m-long, relatively-heavy mobile whip would stress the Ft817’s front (BNC) connector. No idea if that’s practical but worth a try on my next activation.

This. This a thousand times.

The only issue remaining is if they only have an FM set on the end of their “FM” aerial. Now loads and loads of HF sets have had 2m all mode for a hell of a long time. It’s possible that a lot of vertical 2m ops may not have their 2m capable HF set wired as they only do FM on 2m on the FM set. But we have to start somewhere and here is a fine place to start.

I’ll have to remember to check the spots for who may be out to ensure I string up the Jpole and have a bash.

Totally agreed Andy, and as has been said, this presumes that those vertical antennas on the sides of houses, in roofspaces, etc. actually have a multi-mode rig on the end of the coax. Also that there is a willingness to use the mode - some local to me would not be interested.

Hi Gerald, the Ft857 with 50W 2m SSB in my shack is connected to a X50 colinear but sadly I’ve only chased FM activators on VHF since I moved to G/LD last year.

Can’t blame them if nobody’s activating on VHF-SSB. Chicken and egg. We need to provide the chicken, or is it the egg?

Andy, I read this paragraph about 4 times. Unfortunately, I’ve drunk the last of my favourite single-malt when reading a previous posting of you, hence I’ve struggled to understand what you are on about here.

Rigs like the Ft817 can output any mode / band to either front or rear antenna socket. Rigs like the Ft857 have a SO239 for lower bands and a D-type for higher bands, but independent of modes. Are you saying some HF/VHF multi-mode rigs force you to change antenna socket / wiring when changing VHF mode?

If they are switching mode only (FM to SSB) but band (2m) and (vertical) antenna are unchanged, I can’t see the problem.

His point is that they probably have a V/UHF FM only rig connected to their white stick antenna and their DC to daylight rigs connected only to an HF antenna. If its anything like my rat’s nest of wiring they may not be inclined to juggle about with plugs and sockets to do something out of the ordinary for them. I’m OK as I don’t use a seperate FM rig.

I’ve been doing my best to finish off assorted part drunk bottles. Brian interpreted it right!

Ah! You must both be talking about chasers in their shacks. I see the problem now (like you Brian I don’t use a VHF-FM-only rig at home).

Well, to be a VHF-SSB chaser their base station rig would have to be HF/VHF multi-mode with two antenna sockets. That would require either a) connecting the basestation to the VHF antenna (and not using the VHF-FM-only rig) or b) using an antenna switch on the VHF antenna to switch between FM-only rig and the basestation.

H-pol is standard for VHF SSB. I think the idea that you’ll get more take up on V-pol because it makes it easier for habitual FM operators, is both flawed and patronising.

Similarly, the defensive comments distancing the movement from the VHF contest scene are misjudged in my opinion. These people are prime targets to encourage getting involved. The contest scene is a prime example of year-on-year increasing participation on 2m SSB, and should be embraced rather than dismissed.

Don’t try to reinvent the wheel; go with the flow!

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