I am testing for general this Saturday after almost 7 years as a technician, and as a "reward" for passing the test I will be picking up an Icom IC718.  I need some advice on which tuner/antenna to go with.  I am wanting to go multi band and KISS principle so I was thinking of a G5RV antenna.  If this is a good choice what would be a good tuner to go with (I would like one that interrfaces with the control of the 718), and what Balun if anny would I need.  Also, who makes the best G5RV?  Thanks, and wish me luck on Saturday :)

-Space

Instead of the G5RV, which is a good 20m antenna but mediocre on anything else, why not make a dipole?  It won't cost much and you'll learn something in the process.  I've got about $50-60 into my 40/20 fan dipole what with wire, balun and coax.  I run a LDG Z-100 and can run the antenna on 60, 40, 30, 20 and 17.  Oddly enough, it does not work on 15 with the tuner or without.  



Or you could go the doublet route which is just the two longest, equal, lengths of wire strung up and fed with ladder/window line and fed via a balanced tuner.  In theory, it will tune anything higher in frequency than the wire is resonant at.



Good luck with the test!

I have and enjoy the LDG Z-11pro and I like the adjustable C and L so I can fine tune it. It comes with cables to attach both Icom and Yaesu radios.

If you choose to buy the Ultra model from W4RT.com as I did, be aware the battery case they include (6 AA) provides inadequate voltage to run it. You really need an 8-cell case. I have to power it from the external pigtail since the only way to make the 6AA case work is to use super-spankin-new batteries.

A good choice!  I liked the first 718 I had so much I bought another one.

Tuner... the LDG AT-7000 was popular for the Icoms but was replaced with the IT-100.  I'm using one now with my 718.  It plugs into the 718 with a coax jumper (supplied) for radio output to the tuner, and then a short jumper for control.  You can control the tuner from the Tune button on the front of the 718 or from the button on the tuner itself.  Skip the part in the front of the LDG manual, the quick guide.  Go to page 12.  The 718 must have a setting changed in order to work the tuner.  Easy to do.

Balun... depends on what antenna you have.  Dipoles don't need a balun as such, but a 1:1 current balun helps stop RF on the shield.

http://www.hamuniverse.com/balun.html

Other antennas, such as a Carolina Windom, require a 4:1 balun, for example.  This is more a matching transformer to match the impedance of the antenna to the radio.

This is an excellent article on antennas for us duffers:

http://www.hamuniverse.com/n4jaantennabook.html

I'm using a multiband dipole, with segments cut for 75 meters, 40 meters, and 20 meters.  SWR is under 1.5:1 on all three bands*, as low as 1.2:1.  17 m and 15 m are just over 3:1 and the tuner easily tunes these bands.  I've made as many DX QSO's on 15 meters as on the lower bands.

With this antenna I've made QSO's as far away as Argentina (just a few miles short of 5000 mi), Italy, Ireland, Scotland, quite a few to Canada, Central America and the Carribean, many to places I did not even know existed.  I check in on a few nets on 80 meters in the evenings, and have QSO'd up to 1000 miles on 100 w SSB on that band.  There are better antennas, but this got me on the air quickly and with pretty good performance so far, and for minimal cost.

Lots of antenna projects here:

http://www.hamuniverse.com/antennas.html

All practical antennas.


* Well, at least on the 3.8-4.0 mhz portion SWR is good.  It is high down on the 3.5-3.7 portion.  Few antennas will cover the whole 80 m band.

I notice this model has a different connector than the IT100 version.  Does it really interface with the IC718 the same way?

-Space

Thanks, lots of information there!  It looks like the LDG tuner is the way to go then, over the more expensive Icom tuner.  Right now I am looking to buy a high quality off the shelf multiband dipole and then experiment with antennas once I'm on the air.  Any suggestions?  I only mentioned the G5RV because I have seen it everywhere!

-Space

ps I have NO restrictions on antennas in my neighborhood, and live on an acre of wooded forest land with tall trees.

The Icom tuner will handle up to 3:1 SWR, I think is the figure.

http://www.universal-radio.com/catalog/hamtune/2103.html    LDG IT-100, matches up to 10:1




You lucky dog!  

Also do a search for "Super Loop".  You have the room.

I've had good luck with my AH-4 auto tuner.

I recommend a full wave horizontal loop for the lowest band you want operate on! Feed it with balanced line back to the tuner's location and operate all over the place from the lowest resonant band and up! :) It is really great set-up!  I miss my loop...  It came down at the end of winter and haven't had time to put one back up.

Now that's what I'm talking about!  Thanks...now to go find out which two trees to use

-Space

good luck on saturday.

in addition to the fine advice given in the above posts, see also
http://www.ar15.com/forums/topic.html?b=10&f=22&t=604477&page=2#10391681
and
http://www.ar15.com/forums/topic.html?b=10&f=22&t=604477&page=2#10324580

ar-jedi

Good luck on the test. You'll pass it.

This is what I used with my 718. I still use it with my 7000. Great little tuner.

Not really a big fan of the G5RV. I think a fan (mutli-band) dipole would be better. Actually, I do pretty darn well with a balun and a simple piece of wire.

http://www.rlham.com/cgi-bin/shop/modellookup.dbw?MODEL=JTFAN8010BK

MULTIBAND DIPOLE KIT ANY 4 BANDS 10-80

Includes  1:1  Balun,  4  End  Insulators,  375'  14Awg  Wire,  8  Spreaders,  and  100'  1/8"  Nylon  Rope.

This  dipole  kit  may  be  assembled  to  cover  any  4  bands.  10,  12,  15,  17,  20,  30,  40,  60  or  75/80  meters.  Of  course  if  40  is  included  you  will  get  15  meters  as  well  giving  you  5  bands.

I would suggest building it for 75, 40, 20, and 17.  The 40 m segment will give you 15 m with a tuner.

Here's the manufacturer's page:

http://www.jetstream-usa.com/jtfan.shtml



Bypassing the tuner, I'm getting 1.1:1 at 3.9 mhz, 1.3:1 at 7.070 mhz - that was for PSK31 last night, it's lower further up in the phone portion of the band, 1.2:1 at 14.070 mhz - again lower up in the phone portion.  

And you might consider the Carolina Windom.  A friend used one for ARRL Field Day and said they got great performance.  It is very simple and you have the room.  That's simply an off center fed dipole with 44' on one side, 88' on the other fed with a 4:1 balun.*  The one they used was by Radioworks, but there are plenty of plans on the net.  A roll of wire, a 4:1 balun, and some insulators and you are in business.

http://www.packetradio.com/windom.htm  G. E. "Buck" Rogers article on the Windom.  Everything you need to make one is in this article.

http://www.radioelectronicschool.net/files/downloads/ocfdipole.pdf   This is a pdf of the theory, read it.

* Various short and long element lengths are quoted, depending on which plans.  Buck Rogers insists the 4:1 balun, not the 6:1.

That's not a bad kit but I'd probably buy the stuff myself. You can get a 500' spool of 14-ga wire from Home Depot for $25-30. Figure about $25 for a 1:1 balun, $10 for the rope, another $8 or so for dogbone insulators, and a few bucks for spreaders. Price-wise you come out about the same but you have close to 200' of wire left over for other projects. Just my take on it.

I really need to put up a digital antenna. Neither of my current antennas do well in the low portion of 75/80 or 40. I tried to do a 070 contest that was at 3580 and they both sucked. I do ok at 14070 and 7070 but that's about it.

OK!

After reading  the replies, and in the spirit of Ham Radio, I have decided not to purchase an off the shelf antenna.  After all the antenna designs are half the fun, right?  So with everyone's help I have decided to pick up the following (provided I pass the test tomorrow of course):

Icom IC718
LDG Z11pro tuner
LDG DTS-4 Antenna selector

I figure being able to select between antennas on the fly will help me with my antenna designs.  I am going to start out with a random wire, and then a 1/2 wave dipole set up for 80meters.        Is there any advantage between using a 1:4 Balun instead of a 1:1 on a random wire antenna?  







Thanks everybody!

-Space

Choosing the correct balun

FWIW I replaced a $20 balun with a way more expensive DX Engineering unit and noticed a significant difference even running 100W so I think they know what they're talking about.  

Good luck on the test!

Good luck with the test!

Keeping it simple - yeah the G5RV is easy but for other than 20M it's not so great.

Another idea on the dipole (and I just buzzed through this thread, someone else may have mentioned it) - rather than a fan dipole with multiple elements you can just build a single 80M dipole and feed it all the way from the shack with balanced line.  If you're going to use one of the LDG auto tuners you can get the balun they sell, or make one, to connect the feedline.  Using balanced line will eliminate most of the loss you'd get from coax and you'll get a lot more power to the antenna.

For myself, I haven't quite embraced auto tuners yet and I use a MFJ 941E manual tuner which has a balun built in.  It'll tune just about anything.

Took the test this morning, pleased to see they now give it on computer instead of paper.  I passed with a score of 100%!  They convinced me to try for extra and I failed .  I only needed 4 more right answers tho, so I will probably begin studying for that test next  Thanks everyone!

-Space
"Temporary AG "

Wow...great read but some expensive Baluns :)

CONGRATS on the General!!!

Balun, you don't have to spend a fortune.

http://www.universal-radio.com/catalog/antsup/1888.html

There you go, reasonably water resistant.

For a 1:1 current baluns, besides the "Ugly Balun", which I have on my multi dipole, you can also use a string of ferrite beads on the coax up by the feedpoint.  Look at www.palomarengineers.com.

Ugly Balun:





Ferrite Bead choke balun:





The center hanger in the first photo, the SO-239 socket got some water in it.  I replaced it with this:

Jetstream dipole hanger with a piece of plastic kitchen cutting board bolted on to form a multiband dipole hanger.