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kf4jqd
04-25-2010, 08:23 AM
I am glad to see this part of the forum. Antennas ARE the most important part of of station. If you have a $10,000 station but you have a crappy antenna, ie G%RV, you wont be happy!

Back in my CB radio days, people came to me about amplifiers. The first thing I asked them is, Can I look at your set up? What I found startled me. They had a very nice radio connected to the cheapest and worst antennas on the market! I told them the cheapest way to go is get a good antenna. I always recommend the Radio Shack Deluxe mag-mount (Yes I said Radio Shack!). K40's, or Wilson's. They were much happier after they replaced their antenna!

Now, we Ham's has a complex that we are better than CBer's. NOT TRUE! I've talked to guys on the radio who spent thousands of dollars on their radios, but puts up a G5RV. (I do like to pick on this antenna!) They complain to me on 75m. "Andy you are 40 over and you say you are only using your TS440 and 100W?"

I use a bazooka on 75m. It's a damn good antenna.

I hear new hams asking about what type of antenna they should put up for HF. I first ask them, "Where and who do you want to talk too?" This is very important. After they tell me. My next question is, "How much room you have?"

Here's an example or two:
If you like to chase DX on 20m. A beam up 75 feet will do wonders. A dipole a few feet off the ground, you'll have a very hard time.

If you like to rag chew on 75m at night with your buddies. A vertical is NOT the best choice ,nor is a G5RV!

In conclusion, people needs to do their homework. I've heard many bias people on the air about antennas. I don't like QST because you will read how good the G5RV is. Then turn to the back ad see ads for that same antenna. EXPERIMENT! Did you know by adding a wire under your dipole. You can increase your signal without an amp?!

Before spending thousands more on an amp. Take a look at your antenna(s). Improve those first. Do your homework. What may work for me may not work for you.

I do not claim to be a know it all. I am also still learning after 20 years of being in this hobby. Don't be afraid to ask someone. Ask that old timer. Ask that DXer. Ask that contester. Most important, listen carefully to those who have the strongest signals on the band. You just may learn something from them! :bbh:

Andy KF4JQD

WØTKX
04-25-2010, 09:08 AM
I'm a fan of loopiness. :mrgreen:

But mine is broken, and I'm running an inverted Vee doublet fed with ladder line with a Dentron Supertuner. Feedpoint is up about 55'. It's about 110', slightly OCF for convenience. Have a Gap Titan as well, but it's best on 30m and up.

G5RV is a gain antenna on 20M, that works on the other bands, but not that well. If it's really high in the air, it will perform better on the lower bands, but it's a compromise.

Like speakers for a sound system, antennas are really important. It's the part that puts out the energy into space... mechanical compression/decompression for sound, EMF for radio. Eh, lenses for light as well.

It's scientifical. :mrgreen:

N8YX
04-25-2010, 09:40 AM
I am glad to see this part of the forum. Antennas ARE the most important part of of station. If you have a $10,000 station but you have a crappy antenna, ie G5RV, you wont be happy!
:snicker: :lol: :rofl: http://www.valkyrieforum.com/forum/smileImages/animated/a15.gif

I guess all that 20 and 12M DX I've been working with mine doesn't count, right?

And I was really surprised at how well the 102-ft version works on 75...

But 40M and up are the bands on which I spend most of my DX time. ZS6BKW's variant of the 'RV (91ft length; 40ft 450-ohm matching section) allows coverage of 40-20-17-12-10M with an SWR of < 2:1 across each.

http://www.reflections.co.nz/index.php/archives/43

Of course, it goes without saying that you must get one of these antennas fairly high up in the air for it to work well - but the same is true for a TH11DX.

kf4jqd
04-25-2010, 09:51 AM
The G5RV was originally designed as a multi-wavelength for 20m. So it will work good there. As for 12m, I had a very hard time tuning one up. Yes, I had one! I even made one! When you above 20m, the antenna works poorly. Suggestion: Replace the 300 line and coax with 450 ladder line and add 9 more feet on each end. It'll work like a champ!

Andy KF4JQD

N8YX
04-25-2010, 10:18 AM
The G5RV was originally designed as a multi-wavelength for 20m.
3/2w, just like a 40M dipole can be used on 15M.


As for 12m, I had a very hard time tuning one up.
102ft top section overall length; 34ft 450-ohm window line (1" conductor spacing). SWR < 1.6:1 across the entire segment.


When you above 20m, the antenna works poorly.
Not true with the original design WRT 24MHz, and certainly not true with the 'BKW variant.


Suggestion: Replace the 300 line and coax with 450 ladder line and add 9 more feet on each end. It'll work like a champ!
That might work for some folks who can run ladder line from the feed point all the way to their balanced tuner, but many cannot - or don't possess such a tuner.

The best thing one can do with the "original" concept is to toss the 300-ohm twin-lead and use 450-ohm ladder line instead. In addition, I have a 1:1 current balun at the coax-to-ladder line transition point and it really knocks received noise down...

N8YX
04-25-2010, 02:20 PM
Readers might wish to see what Tom, W8JI has to say about the G5RV:

http://www.w8ji.com/g5rv_facts.htm

KJ3N
04-25-2010, 02:58 PM
Readers might wish to see what Tom, W8JI has to say about the G5RV:

http://www.w8ji.com/g5rv_facts.htm
I'd like to see those feed-line losses done with RG-58 or RG-8X, since a majority of people use those types of coax. I'm willing to bet the losses go up a lot higher.

N8YX
04-25-2010, 04:20 PM
Readers might wish to see what Tom, W8JI has to say about the G5RV:

http://www.w8ji.com/g5rv_facts.htm
I'd like to see those feed-line losses done with RG-58 or RG-8X, since a majority of people use those types of coax. I'm willing to bet the losses go up a lot higher.
Yep...LMR600, -213 or 9913 is pretty much all I use for medium-length runs at HF.