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 cobweb low level optimum 
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Post cobweb low level optimum
hi guys, users of this antenna may be able to help.

what would the low level optimum height be on a real cobweb?

i am trying to place it as low as i can for less visual impact, some reports say 25/30 feet,

thanks

bob.

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ic 7600 to a Acom 1200s and a multi band cf dipole. and a 139‘ endfed.
ic 7300 with a 4 mtr vertical.
ic 7100 on 2/70/6/4 on fm at home
ic 7000 with a ah-740/duel band antennas on the truck
Raising funds for LUPUS UK.
RSARS 3503.RSGB.


Tue Oct 09, 2018 11:57 am
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 cobweb low level optimum 
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Post Re: cobweb low level optimum
G0WYD wrote:
hi guys, users of this antenna may be able to help.

what would the low level optimum height be on a real cobweb?

i am trying to place it as low as i can for less visual impact, some reports say 25/30 feet,

thanks

bob.


Performance drops off noticeably below 30', but it still works at 15'

An inverted L works better 18 and 14 (and of course 10 7 3.5 and 1.8), and a vertical works better on 21 24 and 28

As an all in one though, it is hard to beat.

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Tue Oct 09, 2018 12:44 pm
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 cobweb low level optimum 
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Post Re: cobweb low level optimum
thank you,

i’ll have a look see what i can do when i get back from a couple days away with the wife,

keep,the cookie jar topped up,

bob.

_________________
ic 7600 to a Acom 1200s and a multi band cf dipole. and a 139‘ endfed.
ic 7300 with a 4 mtr vertical.
ic 7100 on 2/70/6/4 on fm at home
ic 7000 with a ah-740/duel band antennas on the truck
Raising funds for LUPUS UK.
RSARS 3503.RSGB.


Tue Oct 09, 2018 4:06 pm
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 cobweb low level optimum 
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Post Re: cobweb low level optimum
Moving mine from 10 to 15ft made a big difference! Then putting it to 25ft, it's very hard to tell the difference...

So I'd say minimum 15ft. :good:

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Tue Oct 09, 2018 9:13 pm
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 cobweb low level optimum 
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Post Re: cobweb low level optimum
Essentially... it's a dipole(s). 1/2 wavelength at the lowest band.

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Tue Oct 09, 2018 11:03 pm
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 cobweb low level optimum 
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Post Re: cobweb low level optimum
My MFJ cobweb is up at about 26 feet and has done well, especially on 20 meters.

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Wed Oct 10, 2018 1:52 pm
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 cobweb low level optimum 
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Post Re: cobweb low level optimum
Home built cobweb. Up at 10 ft

First call 4.5 Watts, xiegu x1m, Saudi Arabia

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Wed Oct 10, 2018 10:00 pm
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 cobweb low level optimum 
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Post Re: cobweb low level optimum
M6XMA wrote:
Home built cobweb. Up at 10 ft

First call 4.5 Watts, xiegu x1m, Saudi Arabia


cheers lads,

i think i will be able to get it to about 20’ maybe 25’ so that will have to do me.

regards

bob.

_________________
ic 7600 to a Acom 1200s and a multi band cf dipole. and a 139‘ endfed.
ic 7300 with a 4 mtr vertical.
ic 7100 on 2/70/6/4 on fm at home
ic 7000 with a ah-740/duel band antennas on the truck
Raising funds for LUPUS UK.
RSARS 3503.RSGB.


Fri Oct 12, 2018 7:41 pm
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