PAC-12 antenna

Started by NWARadio, September 16, 2016, 09:44:48 PM

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NWARadio

Any thoughts on this antenna:
http://www.qrpkits.com/pac12.html

I'm wondering if it'd be worth it to try and homebrew one or just buy the one on the site. Anybody here have experience with this antenna? Or one like it?
So long, and thanks for all the fish

cockpitbob

I home brewed the same thing.  It works.  There's no magic to this type of antenna.  It's a coil in the middle of a vertical.  I use 2 counterpoise wires on SOTABeams winders.  I mark the wires so I can unspool the correct length for the band and I get a good SWR.  I have a ferrite bead (choke ballun) on the feed line so it doesn't act like a counterpoise, so only the 2 1/2wave resonant wires on the ground.

I don't think I would bother with the 80meter coil kit.  That's just too long a wavelength to make sense for a short antenna.

For my homebrew I used scrap tent poles below the coil and an MFJ telecsoping antenna above the coil (8' long one I think).  So my overall length is about14'.  The coil wire I got by taking apart 12gauge romex house wire.

gil

Just like a Buddistick but a bit cheaper. They do work surprisingly well, at least using CW, but I have seen videos of people making contacts on SSB using 5W with this type of antenna. My Buddistick was good down to 30m, which seems to be the limit for something that short.

Gil

NWARadio

I've got 5 acres out in the country where my wife and I keep an RV to use as a cabin. I'm thinking of getting a transceiver (I'd love recommendations on brands/models/bands, btw) that's small and easy to toss in the truck and take out there with me to use after the sun goes down and there's no work to do. I'd like an antenna that's quick and easy to put up, but compact and easily stored in the RV or the shed. Although, now that I think about it, I don't want any permanent radials on the ground. Would I be better off with a dipole?
So long, and thanks for all the fish

gil

Are there trees around? If not, you could always get a 33ft telescopic fiberglass pole.. Put copper tape inside each tube, bingo! Instant 33ft antenna! The EARCHI (9:1) or a Ruthroff (5:1) UNUN would work great with it. Add a small tuner and you have a multi-band antenna; no radials needed if you use a 25ft coax cable.

As to the radio, the big question is: Do you have grid power?

Gil

cockpitbob

Again, if you have trees you're all set.  If you don't want a tuner, there's several multi-band end fed half wave antennas you can buy.  Or buy or make an off center fed dipole (Windom) that won't need a tuner on several bands.  I like end feds because you only need 1 tree and your feed point is close to the ground at the end of the wire, not way up there in the middle of the wire.

When you get a line over the tree, make it a loop (halyard) so you can raise and lower your antenna when you want.

For most people the 40m and 20m bands are where they spend most of their time.  If you want Dx, then the shorter bands work better IF propagation is good.  We are heading into about 6 years of low sunspot activity and even now I can't remember the last contact I mad on 15m or a shorter band.  80m will be great for night time non-Dx stuff.  It will be NVIS propagation with means you'll have reliable contacts within about a 400 mile radius.  If you are into Morse, you'll probably want 30m too as that's a non-SSB band and a good propagation compromise between 40m and 20m.

gil

Good points Bob. A good end-fed to buy is the PAR 40/20/10 from LNR Precision. I kinda sorta works on 15m too.

Gil

NWARadio

Yes to grid power and yes to trees. Tons of trees. I'd rather buy an antenna, even though it seems to go against traditional ham thought. Honestly, I just like the look of store bought stuff. It's always better looking and more durable than I can build. Cheaper, usually, too. I just have to get a radio. I'm currently between rigs. I've built a RockMite, but a chip was bad. The Yahoo group helped me trouble-shoot it, which is how I found out it was a bad IC. I'd try another RM, but I'd really like more than a couple of frequencies.
So long, and thanks for all the fish

cockpitbob

If I were in your shoes, here's the antenna I would get.
http://myantennas.com/wp/product/efhw-8010/

It's an end-fed wire that gets you pretty much every band from 80m to 10m without a tuner.  Once I fix my noise problems at home (S7 on most bands I use) this is the antenna I'm getting for my "upstairs shack".

I think it's a little expensive for what it is, but the designer has definitely got the "secret sauce" and can charge for it.  I've designed my share of similar antennas but have never achieved the number of bands or power levels he has (no one else has either).  It's got 36 reviews on eHam.com with a score of 5.0/5. 

Lamewolf

A hunk of wire if its long enough will be much more efficient than the PAC12 ever could be.  The PAC12 will work but requires being tuned to frequency to work properly, but a wire of 33' to 130' fed with a tuner will work much much better.  If you want store bought, there are tons of ready made wire antennas out there and you have lots of trees to hang them from, you will be more pleased with the operation of these than you would that puny little PAC12 !  With antennas, BIGGER IS BETTER !

gil

I agree with Lamewolf. You have a tuner and trees, all you need is a length of wire and maybe an UNUN.

Gil

Lamewolf