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Using 2M FM for Activations


#61

Wow, what a lot of posts and maybe a bit of emotion too.
The reasoning I apply to this is: Use HF QRO if possible, then HF QRP if it’s a long carry but if frostbite and hypothermia are possibilities, I use 2m-FM-only then get out of there fast!

There are many other considerations of course, time available, simplicity, weight, multiple activations in the day etc.

Hope I will work you on 14 MHz one day.
73, John
(GX0OOO/P for SOTA)


#62

Even though the original post is very old, I would like to add something to ponder.

First, I am a SOTA newbie. With only one exception, all of my SOTA activations have been 2m VHF. I invested a great deal of time in the gear I would use, including testing several models of 2m radios for receiver front end rejection and overload resistance. I built several antennas, the most used being a foldable 2 element quad that fits into a small bag and a foldable 3 element yagi which has a boom that doubles as a hiking stick.

I discovered that the Radio Shack HT 202 and the Icom IC-2 had excellent front ends with very good sensitivity. I then acquired perfect examples of each, went through them on the bench and made sure they were 100%. I assembled a small fanny pack that contains everything needed including backup radio, 2 battery packs for the radios that use AA alkaline cells, extra batteries, pepper spray, snacks and water. It all lives in my work truck and is ready to deploy at a moment’s notice. The fanny pack is small and light, and easy to hike with in all conditions.

So, you might say I don’t just use a cheapie HT and give little thought or planning to activations. I put a great deal of thought and preparation into my 2m activations, and so far am having a LOT of fun! I have been first to activate a few summits, and have scheduled several more not-yet activated summits for this year. If I had to drag a backpack full of HF gear to some of these not yet activated summit sites, it would simply never happen.

So, it’s either 2m activation or no activation at all. Besides, I like 2m FM because I can actually hear what people are saying. My hearing is still very sensitive, but nerve damage from a stroke has almost eliminated my ability to copy CW anymore (I used to be a CW OP). That same nerve damage also makes SSB a tough copy for me. Same problem copying people on digital cellphones.

SOTA has something to offer just about everybody. For me, it is FM mode activations, and for simplicity’s sake, it means 2m FM activations. If SOTA offers you something more, that’s great! Why get all upset if what SOTA offers you and me are different?

Very best to you, and 73!

Paul


#63

Paul,

I think you have exactly the right SOTA attitude: curious and experimental.

73, Andy

BTW: for British readers who might think ‘fanny pack’ sounds a bit naughty, it translates to our ‘bum bag’.


#64

Is the pepper spray for your sandwiches? :wink:


#65

My xyl (M3ULV) is number 1 in the world for chasers on 6m fm with 94 points :slight_smile: :slight_smile:


#66

Should have added that I am number 3 activator on 6m fm using a vx7r handi with rubber duck.
I always tried to start or finish an activation with a contact on 50mHz.
Most activations were done on 2 or 70 with the Yaesu vx7r.


#67

Mostly for the 2-legged snakes.


#68

I use several types of antenna that improve hugely on the range available from the typical stubby helical “antenna” provided with HTs.

One option is to purchase a telescopic antenna that extends to a quarter wavelength for 2m, about 50cm or 19 inches. This antenna has provided an extra couple of S units over the stubby. They are available with either BNC or SMA plugs. I don’t recommend walking with one of these on your HT, too liable to be damaged - they are not as robust as the helicals, but for the extra distance the provide they are worth carrying with you.

There are even longer telescopic antennas, which seem to increase the range even further. Even more unwieldy but when you suddenly hear someone who was just not there on your smaller antenna, it is worth having it in the pack.

The second option is to use a vertical dipole on a pole. It can be centre fed, requiring an offset boom to get the feedline away from the antenna, as far as possible but I find even 50cm is enough to allow the antenna to work well. I use electrical conduit fittings to attach and offset a dipole from a fibreglass pole.

But for simplicity the coaxial dipole designed and published by VK2ZOI as the “flower pot vertical” and popularised in SOTA circles by Andrew VK1AD is the winner in my view. To support it, you do need a pole of some kind but it weighs almost nothing so one of the thin fishing poles purchased on ebay will do the trick very well. And to make it, you just need some coaxial cable (RG58 type is adequate) and to be able to measure, cut, wind 9 turns on a 25mm former, put a plug onto the cable that suits your radio and then stand back as the big signals pour in and you get complimentary signal reports from far afield. See https://vk1nam.wordpress.com/2m-coaxial-dipole-antenna/ for details.

I’d also echo the suggestions to try horizontal polarisation with your HT, either with the stubby helical or better yet with the quarter wave antenna. Our experience in VK1 has been consistently better signals when using horizontal polarisation, with all other factors constant. Theories abound about whether horizontal polarisation is less affected by (vertical) trees than a vertical polarisation is, or whether it enjoys lower loss at refraction points, but we will always go to horizontal polarisation when signals are low on the verticals. Log the contacts and worry about the science later.

73 Andrew VK1DA/VK2UH


#69

There are some things that makes a hardcore SOTA activist smile or shake his head:

Roads and cable car to the summit, FM handsets in densely populated areas, digital modes that makes contacts while drinking coffee. Maybe not the pure sota thought.

But it’s all part of it.

If there was still vhf community like 30 years ago, I would immediately be active in vhf doing ssb / cw for 2m DX… certainly with the same effort for the antenna as for hf. Maybe i’ll do it someday. In the 80s I had qso with my IC 202 (3 Watts) and hb9cv from the southern part of the Black Forrest to G and EA. It was pure fun.


#70

I was talking with John, VK2ZOI the other day, when we had a project day of building a 40m dipole at one of the local radio societies in Sydney, about his “Flower Pot” and mentioned how it was being adopted by many in the SOTA world. The design he tells me goes back to the 1930’s or something, he’s just publicising and refining it he says. He also said he gets lots of messages about building the antenna from all over the world, the most crucial bit (and common error he identifies) is the 25mm former. If you don’t use 25mm then it won’t work.

His most out there question was from a vet in NA who wanted to build it to get better range on is foal delivery alert device. Apparently the mare is stitched appropriately and when the stitch is broken that opens a circuit which then turns on a low power transmitter which then alerts the hired help that the foal is on their way. He needed the antenna for 700 or something MHz.

Compton


#71

The 25mm diameter and the number of turns combine with the capacitance between turns to resonate on 146 mhz. Using a different diameter should just mean adjusting the number of turns, or their spacing, to achieve the same resonance. It is effectively a trap for the current on the outside of the coax. In other designs there is another identical trap another quarter wave down the coax, to increase the impedance to current on the outside of the cable.

Yes also I talked with John VK2ZOI recently on 80m one night and he seemed quite pleased to know that the design is being used by SOTA ops. I heard about the 40m dipole construction day. I hope it went well enough to encourage the group to continue making their own antennas.

Andrew VK1DA/VK2UH


#72

I normally activate only on HF CW, but recently I was up in the mountains of northern Georgia (the US state, not the country) to do maintenance work on the Appalachian Trail, and threw the HT and a 300 ohm twinlead J-pole antenna into the pack. Walking out after the work was done, I called on 146.52 and to my surprise immediately had three ops calling back, including one S2S. Turned out there is an active community of SOTA ops living in the general area who routinely activate various peaks. Seems like a great and close-knit bunch. Only on VHF FM, with its LOS propagation, would you find this.


#73

And it still is. Some say 2m is dead but it’s only a bit stinky. :wink:
I’ve been mostly activating 2m SSB for the last two and a half years. Very seldom I didn’t qualify the summit. 23 entities and almost 100 squares worked from the rucksack sounds like fun, doesn’t?
You shold give it a try again.

Ahoi
Pom


#74

I’m at the point where I’m trying to do more 2m fm. I first activated the mode in Scotland because I couldn’t fly over with hf equipment. 2m fm was a blast. I had four s2s contacts in W4G recently and it was so fun I decided to do better on that mode.

The problem is my primary activating area in West Texas has hardly anyone within line of sight.


#75

It’s quite common to get S2S contacts well past line of sight on 2m. Better antennas help. Often using horizontal polarisation is better than vertical, even with an HT tipping it sideways at each end can bring signals up from scratchy to clear. Those wide spaces would help extend the range, I would think.

Ssb is better for weak signal work than fm, if you can do that, but there are usually fewer activators using ssb. 100 km is business as usual for a pair of FT817s on 2m SSB. 200km depending on terrain.

Andrew VK1DA/VK2UH


#76

Like many others, 2-meter FM was my start in SOTA. My first SOTA contact was a chase of KK6ZLY, who was 40 miles away from my home, on Mount Diablo in California. We were both using 5-watt HTs and I was indoors. It was my first simplex contact of any distance and quite exciting for a brand-new ham like myself. It was my first exposure to SOTA–within an hour I had registered and logged my first chase.

I also recall how exciting it was during one of my first activations when, with a 5-watt HT and a homebrew 3/8-wave groundplane antenna, I logged a contact at a distance of approximately 130 miles.

As has already been stated here, VHF (and UHF) are a great entry into SOTA for new hams. Even though I now mostly operate SSB, I still occasionally call CQ on 2 meters or 70 cm FM as well–not only is it interesting to hear how far my signals reach from an elevation, but I may also be exposing SOTA to potential new “recruits.”

73, Steve W6SAE