Small, lightweight antenna that will cover VHF+ bands? (50-1296?) Log periodic?
Hi all - is there a small antenna that could be used for hiking/mountaintopping (mostly SSB) that would cover many/all of the VHF bands? I'm thinking 50, 144, 222, 432, and 1296. I've heard of some log periodic antennas that may do this, but I think they're quite large and I don't know the specifics. Can anyone that has one, or know of one, chime in? I'm interested in something that can easily be broken down for hiking, or just throwing in the car to go to a local hilltop.
Second question - suppose I find an antenna that serves this purpose. Most likely it will have only 1 antenna connection. The radio that I'll be using is a TS-2000X, which has antenna jacks for 50, 144, 432, and 1296. Additionally, if I decided to go with a 222 transverter, that will have its own antenna jack as well. Is a large switch recommended and I'd just switch between bands as I'm switching them on the radio as well? If I take my FT-817 backpacking that has 1 antenna jack for 50, 144, and 432, but if I had a 222 transverter, that will have its own antenna jack, so now I'd have 2 jacks to get into the 1 antenna jack. I'm curious how easy/hard this setup could be.
Thanks for your advice/recommendations!
My first thought was to use a discone antenna but one that is a real discone for 50-1296 is large and could be very heavy when in relationship to backpacking. There is a sort of hybrid type of discone you can get from several manufacturers. An example is here; http://www.rfparts.com/diamond/d130j.html.
The stated gain of the antenna is actually above the usual gain of zero that a discone has. It will work better than any rubber duckie antenna though. A LPDA made from wire would be a good thing to try but again it would take a bit of wire to make it for the full coverage you want. That and the fact that it could become more of a tangled mess than an antenna is going to be a problem.
Something that will work is to make a 1/4 wave vertical ground plane and those would be small and easy to make. The problem is you want to work SSB and hortizontal is required for those bands. A simple dipole for the VHF bands would work much better and can be very light weight and easy to setup. The UHF bands will likely need something with more punch and it would be very easy to make a directive array for those bands. Unless you need to monitor more than one band at a time then all you would need is one good quality feedline.
Something to consider would be a variation on the quagi antenna. On the VHF bands a cubical quad will work well. Once you get higher in frequency the effectiness of a multi-element cubical quad reduces in performance when compared to a yagi. The cubical or full wave loop does maintain good functionality though and is often used as a driven element in antennas through the 1300Mhz range. That's another consideration to think about. It's all going to come down to what will easily setup and perform the way you want.
There are LPDA for coverage in the areas you want and you will have to decide if they will work for you. Here is one example; http://www.medav.de/fileadmin/redakt...s_logper.pdf?a.
There are others but this gives you an example of what is required.
BTW the switching you would need for use up to 1300Mhz needs a good quality unit. Those made by Bird are very good and their price reflects that. Getting them used would be the best idea.
Hope this helps
That LPDA linked above weighs a whoppin' 50 kilos! Wonder if they are made out of steel?
For hiking/hilltopping I'd go with a Create 50-1296 log which weighs 11 pounds.
Forgot to mention that if you use a 222 xvrtr that most rigs will use the 28 mHz IF---so connecting it to your rig wouldn't necessitate externally switching the inputs. You might need a delay line, though.
If the Create log array is still too cumbersome you might also consider an Elk Antennas 2 meter log that also works very well on 432 mHz. You'd have to either go with a small (2 or 3 el) Yagi (or Moxon or dipole or HO loop) for 50mHz and perhaps a Quagi or wire Yagi for 222 & 1296 to complete your arsenal.
I used to do a lot of hilltopping on all of these bands a long time ago; it was great fun!
The difference was that I always had them mounted atop my car or another post I stuck in the hill so when I drove up there I'd be all set up in 10 minutes. Sometimes (weekend contests) I'd leave my 5 element 6M beam up there inside the galvanized pipe so when I came back next day all I'd have to do was attach the coax.
Hiking in might be another story and I'd opt for the Create antenna and be done with it. All you'd have to do is remove the three longest elements when backpacking in. Maybe the boom could double as a walking stick, too.
PS: Check out WG0AT's SOTA adventures with his goats, he does some great videos and uses Buddipole folding antennas (but for HF).
Thanks for the feedback guys! I like the log periodic idea, however the Create 5130-1N might be too big for hiking/backpacking. It says the longest elements are almost 10 feet long! For anyone that has one of these, are they possible to break down very easily for hiking?
Let's say I go with a LPDA...
My TS-2000X has a coax jack for 6M, 2M, 70CM, 1.2GHz. Would I have to get a 4 port switch to switch between each band to the 1 coax feed to the LPDA? If I added a 222 transverter, then I'd need a 5 port switch. Any recommendations? I assume they don't make a quad or pent-plexer so I can skip the switch altogether?
A high quality UHF coax switch could to this job okay with almost zero loss. Look for a Bird 78 swtich, they're very popular and have no loss at 1.2 GHz.
The Create LPDA isn't so bad (I have two of them) but the Tennadyne T-28 might be better (I don't have one, but the Tennadyne appears to be better built).
Of course the longest element needs to be at least 10' long to cover six meters, that's the way they work. It's pretty easy to disassemble and reassemble in the field.
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