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 5 band cobweb tuning 
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Post 5 band cobweb tuning
I have a 5 band cobweb and need some advice on best way to get swr down . I have taken some reading from the radio end of coax as antenna end I have to climb ontop of my shed .. iv taken reading of lowest and highest on each band .I know the if you adjust swr on 1 band another will go up ,so how the best way to start .my cobweb is on a 35 foot motorised tower Thnaks


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Sun Apr 14, 2019 2:26 pm
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 5 band cobweb tuning 
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Post Re: 5 band cobweb tuning
The best way is to adjust it in a place you can get to it, ie on about a 12' pole.

I got mine nearly right, then put it on the final pole, and noted the amount each band changed from the 12' pole to the final pole, then bought it down and did the final adjustments with the offset for the difference.

Once you have it nearly right, the interaction between the bands is small.

I did the initial adjustments about 6' off the ground so that I could reach it easily.

It was the quickest and easiest multiband antenna I have ever adjusted :)

I did mine on the drive with the cars parked across the street.


Looking at the readings, why do you want to adjust it???

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Sun Apr 14, 2019 2:34 pm
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 5 band cobweb tuning 
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Post Re: 5 band cobweb tuning
Sangoma wrote:
The best way is to adjust it in a place you can get to it, ie on about a 12' pole.

I got mine nearly right, then put it on the final pole, and noted the amount each band changed from the 12' pole to the final pole, then bought it down and did the final adjustments with the offset for the difference.

Once you have it nearly right, the interaction between the bands is small.

I did the initial adjustments about 6' off the ground so that I could reach it easily.

It was the quickest and easiest multiband antenna I have ever adjusted :)

I did mine on the drive with the cars parked across the street.


Looking at the readings, why do you want to adjust it???

on 10m 5.2 my tuner wont get the down in 20m is ok just wanted to fine tune abit . Thanks by the way my 80 now id under 1.3 all thru


Sun Apr 14, 2019 2:54 pm
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 5 band cobweb tuning 
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Post Re: 5 band cobweb tuning
Forget it the cobweb is narrow on 10 well mine is, it's bang on for voice or CW so I'd leave it well alone as you are just chasing an illusion expecting a cobweb to cover much on 10!
Nowt much on the FM portion anyway in fact 10 is quiet at the minute not many openings.

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Sun Apr 14, 2019 3:00 pm
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 5 band cobweb tuning 
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Post Re: 5 band cobweb tuning
Sangoma wrote:
The best way is to adjust it in a place you can get to it, ie on about a 12' pole.

I got mine nearly right, then put it on the final pole, and noted the amount each band changed from the 12' pole to the final pole, then bought it down and did the final adjustments with the offset for the difference.

Once you have it nearly right, the interaction between the bands is small.

I did the initial adjustments about 6' off the ground so that I could reach it easily.

It was the quickest and easiest multiband antenna I have ever adjusted :)

I did mine on the drive with the cars parked across the street.
I have a 6ft speaker stand I can use and put it on the grass part of the garden as doit from there

Looking at the readings, why do you want to adjust it???


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Mon Apr 15, 2019 8:14 am
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 5 band cobweb tuning 
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Post Re: 5 band cobweb tuning
If you tune it at 6 foot you will find the swr dip changes a few khz upwards when raised to 30 foot
you need to take this into account when tuning.

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Mon Apr 15, 2019 3:29 pm
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 5 band cobweb tuning 
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Post Re: 5 band cobweb tuning
[quote="G0JUR"]If you tune it at 6 foot you will find the swr dip changes a few khz upwards when raised to 30 foot
you need to take this into account when tuning
I have a telescopic 10m ali pole maybe that would be better use first 2 sections


Tue Apr 16, 2019 7:41 am
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 5 band cobweb tuning 
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Post Re: 5 band cobweb tuning
iv tried twice now to get 20m down the lowest is 1.9 and the wire at 1.9 on 14.350 is really loose don't know what happened it was under 1.5 all thru when I put it up


Sat Apr 20, 2019 5:19 pm
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 5 band cobweb tuning 
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Post Re: 5 band cobweb tuning
Sangoma wrote:
The best way is to adjust it in a place you can get to it, ie on about a 12' pole.

I got mine nearly right, then put it on the final pole, and noted the amount each band changed from the 12' pole to the final pole, then bought it down and did the final adjustments with the offset for the difference.

Once you have it nearly right, the interaction between the bands is small.

I did the initial adjustments about 6' off the ground so that I could reach it easily.

It was the quickest and easiest multiband antenna I have ever adjusted :)

I did mine on the drive with the cars parked across the street.


Looking at the readings, why do you want to adjust it???

My thoughts exactly, I could live and work with those results!

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Sat Apr 20, 2019 6:08 pm
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 5 band cobweb tuning 
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Post Re: 5 band cobweb tuning
M6NQW wrote:
iv tried twice now to get 20m down the lowest is 1.9 and the wire at 1.9 on 14.350 is really loose don't know what happened it was under 1.5 all thru when I put it up


Did you adjust any of the other bands because changing one can effect the others to some extent but like the others have said it was perfectly fine as it was.
Not sure if you have an original but the copied ones can be a bit hit and miss and i prefer the single wire G3TXQ design.

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Sun Apr 21, 2019 8:47 pm
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 5 band cobweb tuning 
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Post Re: 5 band cobweb tuning
g7pan wrote:
M6NQW wrote:
iv tried twice now to get 20m down the lowest is 1.9 and the wire at 1.9 on 14.350 is really loose don't know what happened it was under 1.5 all thru when I put it up


Did you adjust any of the other bands because changing one can effect the others to some extent but like the others have said it was perfectly fine as it was.
Not sure if you have an original but the copied ones can be a bit hit and miss and i prefer the single wire G3TXQ design.

im getting there its taking time as I have to climb on the shed and of then up n down stairs but done 20m and 17m 15mand 12 over the next couple of days breather inbetween


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Sun Apr 21, 2019 9:10 pm
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 5 band cobweb tuning 
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Post Re: 5 band cobweb tuning
g7pan wrote:
M6NQW wrote:
iv tried twice now to get 20m down the lowest is 1.9 and the wire at 1.9 on 14.350 is really loose don't know what happened it was under 1.5 all thru when I put it up


Did you adjust any of the other bands because changing one can effect the others to some extent but like the others have said it was perfectly fine as it was.
Not sure if you have an original but the copied ones can be a bit hit and miss and i prefer the single wire G3TXQ design.


Sun Apr 21, 2019 9:14 pm
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