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 G5 or doublet 
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Post G5 or doublet
half size g5 or doublet with slightly longer legs ( maybe an extra 6 foot per leg on a half size g5) and fed with 600 ohm roughly the same length as the g5 ladderline ... 40m being the lowest band of interest.

just till i get a loop back up ..


billy

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Voice is for CBers, amateur radio operators, the average citizen, and the military. In other words, voice is for everyone with a mouth. CW is for those who choose this newer mode of communication. Newer? Why yes. Voice has been around for a million years.


Fri Oct 07, 2011 3:51 pm
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 G5 or doublet 
Silent Key

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Post Re: G5 or doublet
Billy,

I assume that if the doublet feedline length is the same as G5RV/Jr ladderline length then you wouldn't have much coax on the G5RV/Jr. If that's correct I doubt you'd notice any difference between the two.

But the theory says marginally less loss on the doublet.

73,
Steve G3TXQ


Fri Oct 07, 2011 4:29 pm
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 G5 or doublet 
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ok steve, as i thought .. i may go with the G5 as i could probably get it horizontal at a uniform height with a bit of tinkering and also have the ladderline coming away vertically . It would only be temp depending on it's performance as i want to get my full wave loop back up but fed for multiband use this time ...

got a qso into france lastnight using the old tv coax hanging off the roof fed against the scaffolding that's round the house :lol: couple of days without an antenna was getting to me :lol:

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Fri Oct 07, 2011 7:03 pm
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 G5 or doublet 
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Post Re: G5 or doublet
billy ive just done a antenna 90ft top and 40 ft 450ohm feeder got the details off m0ska working great resonant on 40mtrs if u want details send me a email and i will send on paul.tose@yahoo.com cheers paul m0cln


Fri Oct 07, 2011 9:17 pm
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 G5 or doublet 
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Unfortunantly not got 90 foot for a horizontal top paul .. That's why i went with a loop originally as i could get the 140 odd foot in a delta loop on my plot.. The loop has worked a dream for me on 40m for short haul stuff but not great at all for DX on 40 but i was busy trying to get my FISTS awards on 40 inter G anyway.. which i have now done :D

I have worked DX on other bands with it although it is really set up monoband so i recon if i feed it for multiband use i should do ok ..It will only be temp anyway as i want to hang the next loop well, the last one was supposed to be a temp antenna but stayed up 2 + years :lol:

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Fri Oct 07, 2011 9:31 pm
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 G5 or doublet 
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Post Re: G5 or doublet
try a windom it will pee all over g5 even my home brew one kicks the hell out of g5 lets face it g5 is like using a dummy load mounted high in the sky they are very simple to make and cost less then the 300 ohn ribben feed http://www.packetradio.com/windom.htm make your own balun and away you go its simple to make and works very well if i can hear it i can work it ,, from aplex down to 3 mtrs in and l 60 foot stright and 6 side ways best i have ever used


m0jha wrote:
half size g5 or doublet with slightly longer legs ( maybe an extra 6 foot per leg on a half size g5) and fed with 600 ohm roughly the same length as the g5 ladderline ... 40m being the lowest band of interest.

just till i get a loop back up ..


billy


Sat Oct 08, 2011 9:58 pm
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 G5 or doublet 
Silent Key

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Post Re: G5 or doublet
Its interesting how much 'negative press' the G5RV receives; this was w8JI's experience:

Quote:
On The Air Testing

One of the only ways to reliably test an HF antenna is a blind A-B comparison against another known good reference antenna. Since I also had a dipole at 100 feet a few hundred feet away from the G5RV (similar height), I had an ideal testing situation.
Blind Test

I checked into various groups on 75 meters and did a blind A B antenna test. I would say "this is antenna one one one, this is antenna two two two" while switching antennas. The results were:

1. Nearly ALL of the reports indicated NO difference in signals! (58 equal reports)
2. When a difference in signal was reported, about equally split either the full size dipole or G5RV would win. (7 G5RV better, 9 dipole better)

Announced Tests

I also did tests that called the antennas by name. I would say "This is the the G5RV,G5RV, G5RV. This is the dipole, dipole, dipole". The results were rather revealing.

1. When I would call each antenna by the correct name, the G5RV was reported "weaker" or with "poorer audio" or some other negative comment more than 80% of the time. The remaining stations reported no difference!
2. When I would call each antenna by the opposite name, the antenna I was calling the G5RV was still reported in some negative context about 80% of the time. The remaining percentage again reported no real difference.


73,
Steve G3TXQ


Sun Oct 09, 2011 12:02 pm
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 G5 or doublet 
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Post Re: G5 or doublet
i have to agree steve, for some reason the G5 gets a bad press , not sure why though . I think some of it may be down to it not being an exotic design with some wonderful working properties claimed by may other antennas.

Another antenna which doesn't so much get a bad press but seems to be left as a secondary thought is the doublet or dipole antenna. Maybe it's the simplicity and " lack of boasting" cred of these antennas .

I take notes of what the other station is using for antennas and the G5 and the doublet /dipole do very well indeed second or maybe on par to the windoms and the W3DZZ i think its called but defo not a bad antenna .

Now my findings are the LW ( now this depends on the ops understanding of a LW ) and are more likely to be just random end feds are they are pretty much well down on many antennas but this could be for a few reasons.

I used a G5 when i first got licenced and at a decent height worked fine with no issues ..

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Voice is for CBers, amateur radio operators, the average citizen, and the military. In other words, voice is for everyone with a mouth. CW is for those who choose this newer mode of communication. Newer? Why yes. Voice has been around for a million years.


Sun Oct 09, 2011 12:40 pm
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 G5 or doublet 
Silent Key

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Post Re: G5 or doublet
Billy,

I think a lot of the problem is that people don't understand the G5RV well. Its weakness is the coax section - if that is long and small-gauge, the losses will be high on several bands, especially 10m. It also needs a good 1:1 current balun at the coax/ladderline junction.

If folk use a G5RV expecting it to be a good all-band antenna they're likely to be disappointed. But for 80m, 40m and 20m it takes some beating if you don't have the full horizontal space for an 80m half-wave.

73,
Steve G3TXQ


Sun Oct 09, 2011 3:46 pm
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