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Radio kit for activating

I have some kit for activating, Home made 2m antenna made of 450ohm ladder. A choice of handhelds (2m and 2m / 70cm) and mobiles sets of FT7100M or FT-857d.
Hand helds have their own batteries which is nice. Mobile sets dont.

Choice of batteries. I have access (or will do) to some 12v SLABs from UPS’s- maybe a bit heavy?
What do people use for antenna mounts/poles? I have seen 10m fishing poles or 10m telescopic poles such as


which might be strong enough to hang a 2m or maybe a HF long wire off.

open to suggestions/thoughts
cheers
john

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Or if you are feeling flush they do a carbon fibre version.

Have a look at Lifepo4 batteries, a lot lighter than SLAB.

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Learn CW and go ultralight. My entire kit weighs in at 29oz. I don’t count “throw weight” because I use a small bottle of water and drink it during my activation. :slight_smile:

For an antenna, I generally use an arborist rope to hoist and EFHW or Dipole into a tree. Saves the weight of a pole. When I’m going to be in a barren area, I use the SOTAbeams Tactical Mini (shown above).

When I ran an FT818 before converting to CW-Only, I used a 3000mAh LiPo and it lasted at least 2 hours running SSB. Never got it down to the low voltage point.

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Hello John

Many of us do well with poles of just 4m, 5m or 6m in length, 10m is too long and too heavy for me these days and unecessary. As a user of 4 band HF link dipoles used as an inverted vee, having a 5m pole means I can reach the links for 20/30/40/60m from ground level. It also means if you buy a “travel pole” which packs to 57cm it fits inside your rucksack and is out of sight of people you may meet on the trail, so no questions are asked.

Trouble is the shop I use is out of stock at present:
https://lifebreeze.co.uk/collections/travel-telescopic-poles but you might find them somewhere else if you are interested in going down the travel pole route…

Good luck with SOTA!

Phil G4OBK

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Hi John,
My general rule to those starting in SOTA is to use what you have for your first activation, you will learn from that what you need to improve on.

Ideally, do your activation with an experienced SOTA activator so you can learn from her or him and see what equipment they use. In these Pandemic times, that might not be the best idea however but it’s something to do once things get back to a more normal state.

I think you have already realised your first issue - a SLAB is heavy and unless you are going to a “drive-up” summit, I wouldn’t consider it. There are lighter batteries - the LifePo family are probably the best at the moment but they are not cheap. Some build their own battery packs from individual LiFe cells. There are also LIPO batteries that are cheaper than LifePO but need a voltage adjustment to suit the mobile rigs. Both LIPO and LifePO batteries are lightweight but need care when charging (especially the LIPOs) - so a special “balanced charger” is also needed.

I’d recommend if your chosen summit is within range to a large population area, to do your first activation just using your HT - perhaps with a better antenna than the “rubber duck”. Many of us use the telescopic RH-770 which gives some gain. Yes, your 2m J-Pole would be better still but then, as you have pointed out, you need a mast to support it and you’ll most likely want to guy the mast or at least have some way to support the bottom. If there is a convenient fence post or signpost on the summit, that’s useful but if not, how will you stabilise the base of the mast? Some of us use sun umbrella screw in the ground bases. I used to, but have now switched to using a modified surveyors tripod.

For HF - if there are trees on the summit, you could be fine with an end-fed wire antenna with lots of cord on the end of it and just throw it over a limb and haul it up. That’s certainly much less weight to carry than a fibre glass mast and some kind of base.

By the way, if you go with a telescopic pole, I would avoid carbon fibre ones as it might de-tune your 2m J-Pole (probably fine for HF inverted V antennas as they are away from the mast) - fibre glass masts on the other hand are fine with vertical antennas next to them.

It’s good if you know something about the summit that you are going to before you go so that you can avoid carrying stuff that turns out not to be needed.

My advice - try an activation with your 2m handheld first and then decide what you would like to add to the kit.

73 Ed.

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I’ve used this on 60+ activations. At 18 GBP, the price/quality ratio is unbeatable! (URL says 4m but you can choose pole length below the description, up to 6m, which is the one I have)

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Hallo John

I have been using the mini from dx-wire since the beginning. It is 10m long and has a small transport size.
For HF, I mainly use a vertical and attach it to the tip. You can also do this with a wire antenna for 2m.
IMG_2383
Of course, you can also mount a 2m antenna on the mast and a vertical for HF…



the 2m antenna is then in the more stable area of the mast…if you do a little research here, you will find some informative threads.

73 Armin

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I used to use the 10m Mini from DX wire all the time. However, I think that beyond a certain length the mast gets too floppy, so that you have to carry more and more weight whilst getting less and less increase in height (the benefits of which are highly debatable). These days I’m very happy with the Tactical Mini from SOTABEAMS:

Yes, it’s an expensive choice compared to the alternatives, but it is very stiff, and I almost always get the full 6m height and a nice taut antenna. Of course, this all depends on what type of antenna you use, and a thin vertical wire probably works much better on a 10m mast than my 250g 32m Windom.
73 de OE6FEG
Matt

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Many of us have used SLABs and some probably still do. If you have them, and don’t mind carrying the weight then give it a go. I would try them locally first, though, as batteries that have served in a UPS will not be in peak condition…

Lots of ideas here and elswhere on the this Reflector, but I’d endorse Ed @DD5LP 's advice to use what you have to start with, and find out what you’d like to change / add.

Most of all, have fun!

73
Adrian

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I agree that a 10m pole is too long and too heavy …

… except if you want a vertical with groundplane for 30m - then it becomes rather necessary!

… or if you want to go on holiday on an aeroplane and be able to pack it in the hold luggage! (I realise there’s other options now, but that was actually the reason I first bought my 10m Travelmast - but it did facilitate the 10MHz GP idea, which is it’s primary function now).

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I agree with suggestion that you should start with 2m only for the first activation. It would be good if you could spot yourself on the cluster to ensure plenty of contacts, so mobile coverage on the summit would be good. RH770 for 2/70 bands and RH205 2m only are good options for your handheld. If you want to extend your range LPDA or HB9CV antennas could be considered. There are foldable versions available, however they will require short 3-4mtr mast.

I don’t expect that you will find many summits with trees in the UK, so some kind of mast seems to be a must.

I have two, which I use depending on the difficulty of the climb. First mast is a DX-Wire mini (10mtr) which folds into 65cm, however often I don’t use top 4 elements. Before I bought it, I had a cheap 7mtr fiberglass fishing rod from eBay. It folds into 1mtr only, which makes it a pain when going through woods and bushes, as it sticks out of the backpack.

My second mast is a monster, but I use it only on very easy hills. It is also from DX-Wire and it has 13.5mtr in lenght. I hang vertical EFHW40/20/10. Be warn though it’s 2.4kg in weight.

As for the battery, I use Li-ION or LiFePO4 homemade battery packs. Again I choose size depending on how much time I am going to spend on the summit. I take 3Ah (<300g) for a short activation or 5 Ah (<400g) when I plan to be on the summit for 4-6 hours. For an all day event like European SOTA Day in September, I take heavy (1.5kg) 10Ah plus 5Ah and 3Ah. That gives me 10-12hours with my mcHF QRP rig.

Size of the battery is determined by your rig, mode and time you are planning to operate. Let’s say you operate SSB, and your rig draws 0.3A on RX and 2.5A on TX. A SSB generates usually 70/30 operating cycle (70%=RX and 30%=TX), so for each hour at the summit you will need (0.3Ah70%) + (2.5A30%)=0.21A+0.75A=0.96Ah. So if you had 12V 3Ah battery pack it would last just over 3hours.
If you measure current draw on your rig, you can calculate size of the battery you need. Remember that TX current is changing with power level.

Good luck and I hope to do S2S with you soon.

73 de Marek

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Another vote for using what you have to get started. In the US Mid Atlantic region 2m FM is a very productive method, with virtually all summits being suitable for that mode (the exception being the ones hosting radio/cell towers such as W4V/SH-030). An HT with RH770 antenna will work 90% of the time. In fact, I’ve found that combo performs so well, I don’t bother with my jpole any longer. I can literally carry what I need for a summit activation in my pockets as a result.

Chris

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Do you have one of these? I am inclined to believe that it is actually a 6 meter mast since that is what is printed right on the product.

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I use the Tactical Mini and it has worked out great. I can put a SOTABeams 3-band linked dipole on the very top if I either guy the mast or tie it to a bush or other stout vegetation.

Another thing to check out is a brand new product from Spiderbeam:
https://www.spiderbeam.com/product_info.php?info=p427_Spiderbeam%207m%20Mini%20fiberglass%20pole.html&XTCsid=e260d0d65413c2ed29136d50e6e8ffaa

It is a bit heavier than the Tactical Mini but it is 1 meter taller, and given the quality of the 12m Spiderbeam mast I have I’m betting it will be made well. As soon as Spiderbeam.us gets them in stock I am going to order one.

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Thanks for all the replies people, plenty of information to wade through and consider.
Start simple I think and work out from there.
Mast, cables, radios, power, personal safety, lots of considerations.
73
M0VAZ

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I really like the Spiderbeam stuff. I bought the 7m pole which seems ideal for SOTA. I’ve yet to try it out (first outing with it tomorrow) but it seems very sturdy compared to a lot of the other cheap stuff you can buy from the online auction sites!

They also do a 10m version which is only 1cm longer but double the weight (still perfectly manageable for SOTA). I’ve not managed to get my hands on one to have a look though.

I have the 12m Spiderbeam mast which is fantastic for portable operations from the caravan at a campsite but I really wouldn’t want to carry it any great distance up a hill. It’s a bit big & heavy!

I also have the 22m Spiderbeam mast which is basically a permanent fixture at my 3 acre field (used as a 1/4 wave vertical for 80m & a 1/2 wave vertical for 40m). That definitely IS NOT portable!!!

For my upcoming SOTA activations in the next 2-3 days I’m going with a 7m Spiderbeam mast & an EFHW (as an inverted V) driven through a 49:1 transformer resonant on 40m. That should also give me 20m. I also have another shorter wire that I can run as a vertical (either a 1/4 wave on 20m, or other bands with a tuner).

For 2m (which is what you specifically asked about) I would go with what you already have. Some people like to run 10-20 watts or more from radios like the 857 but then you have to carry batteries as well.

Personally I find 2.5 watts (with the option to pump that up to 5 watts on most handhelds) enough to achieve a good result. Anymore power than that & you are into diminishing returns in my view. All you are doing is warming up the sheep on the next hilltop!

If keeping the budget down is important for you, then work with what you already have.

As a side not, some of the lighter coax cables can be EXTREMELY lossy at VHF/UHF frequencies. I once measured the loss of RG-58 on 2m.

A 5 meter length of RG-58 had more loss than a 50m length of Westflex 103 on 145MHz!!!

Unless you plan to haul up low loss coax such as RG-213 or Westfelx 103 to the top of the summit (assuming that a fibreglass mast would take the weight of said feeder cable), adding an additional 5 meters of coax loss to get the antenna to the top of a 10 meter mast (as opposed to just using a 5 meter mast) might not be worth it.

If you are on a SOTA summit, then you are probably already in a good VHF location. Adding a few meters of antenna height probably isn’t going to make much difference.

The problem you will run into on some summits is desense. I’ve found that handhelds are more prone to this than base/mobile radios, especially when you use big external antennas. This can be overcome by adding a bandpass filter.

Just my thoughts, I’m sure that others will disagree!

At the time of posting this there were 15 comments from approximately 11 different people & you are probably going to end up with around 20 different suggestions! Do what works best for you.

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I use a 6m version, from Decathlon and a 7m from Sotabeams. The Decathlon version is only 58cm folded, so actually goes inside my sack.
For batteries I use a LifePo 4s 4.2 mAh which weighs 530gm.

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Kids 4m fibreglass fishing pole loose the top piece as it’s too small in diameter, very light and £10 off ebay. Fits into your rucksack too.
Two walking sticks pushed into the ground at an angle and tied in a cross onto the fishing pole. Works for me for 2m beam. I have only done 4 activations so i am no expert.

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I certainly can relate to many of the points you make James. Based on your comments, here are some more thoughts for John to consider -

It all depends on what you want to do - rely on there being sufficient locals on 2m FM to qualify the summit or look for contacts further afield. I’ve never prescribed to the former approach as there are few summits out here in Middle England and each activation therefore has a lot of planning time, travel and physical effort embodied in it. I aim to qualify a hill, not return home wishing I had. Even so, there have been a few near panic moments along the way.

Looking back I am amazed at what I started with. My first SOTA rig was a Yaesu FT-290R with a Microwave Modules linear run off a 12AH SLAB to a 5 element Tonna on a 5m aluminium pole fed with 6m of RG-213. I wore an old anorak, jeans (certainly not recommended :smile:) and a pair of boots that cost me £30 from the local outdoors shop, purchased for lunchtime walks - waterproof they were not! Absolutely everything has changed over the years, except for that 2m linear. :smiley:

With regards to coaxial cables, many of the 7mm diameter cables have as good if not better loss ratings than RG-213. I use 5D-FB which is similar to LMR300 and Aircell 7. I find it much easier to handle in cold temperatures than RG-58 as you bend it to a radius and it stays put. Worth buying a few metres - the length I use is 5m as the 5 element SOTAbeam sits on the pole at around 4m. For HF I am using RG-174 on a winder, but that can have a mind of its own when it is sub-zero!

I use 7m glass fibre poles, one with the top section for my 20 / 17m vertical and the other without the top section for my HF linked dipoles and 2m beam. The top section of a pole can be made into a very useful vertical for 2m, mine being to details provided by David G0EVV - suitable as a backpack antenna, but I don’t usually use the radio while walking.

One point I would make about batteries is that I have found greater flexibility in purchasing smaller capacity batteries than one large one. Currently I have several LiPOs which run the FT-817 or IC-703 and separate 4.2AH LiFePO4s for the linears. I take what battery power is appropriate for the activation; obviously more if I am doing one hill and then going straight to another without returning to the car. For a normal single hill outing I usually take a 2.2AH LiPO and a 4.2AH LiFePO4.

As for rigs, well we all have our own preferences. My only comment would be that I find a transceiver such as the FT-817 plus a linear is a better option for me relative to an all-in-one rig such as the FT-857D. This is purely on the grounds of battery power requirements. I have both, but the 857 is currently gathering dust.

73, Gerald

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@g4oig - I wont be wearing jeans - learnt that doing Motorosport marshalling.
I have a decent pair of boots that I wear again for Motorosport marshalling/radio/recovery/rescue but these are a bit heavy for yomping up hills.
Batteries are the ones I need to investigate if I am planning on using a mobile set. I have a FT7100m that will do for 2m/70cm and the 857d can stay at home unless HF is being done.
@m0gqc - I think it was densense that was mentioned by another operator if working near bit antenna i.e near Ponderossa.

There are lots of views and thoughts which is excellent.
cheers
john

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