Homebrew 1/4 wave copper pipe dipole

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108EH002
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Homebrew 1/4 wave copper pipe dipole

Post by 108EH002 » 18 Nov 2018, 14:23

Have made a simple 1/4 wave homebrew dipole made with 15mm copper pipe and the coax connections ( live + and earth - ) are held in place with a jubilee clip on each side,each end of the wire being connected,only has to be 25mm or 1 inch in length,and this will be plenty of wire to slip under each jubilee clip.You can insulate each connection with insulation tape just to be safe.Each leg was cut to 102 inch,8 1/2 ft,259 cm or 2.59m in length per leg.I also installed a rf choke about 1ft under the connections from the coax/feedline,which consisted of 6 whole turns on a piece of 4 inch/115mm plastic pipe,held inplace with gaffer tape,and you can also use cable ties to keep it nice and tidy.My homebrew copper pipe dipole is suspended from the attic rafters with fishing line,and is in an inverted V ( looks like /\ ),at the angle of the roof either side ;)

I usually just use copper wire/rg213 but always wanted to try it with copper pipe,just to see.

The swr readings were as follows =

1.3 on 26.965
1.0 on 27.500
1.1 on 27.991.25

Have managed 20 miles today on fm to another local in his house,so not too bad for something in the attic :D

Hope this helps someone in the future,looking for an alternative dipole antenna :thumbup:
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27.781.25 FM
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Re: Homebrew 1/4 wave copper pipe dipole

Post by 108EH002 » 27 Dec 2018, 23:15

After doing some further research I have changed the distance of the rf choke,the rf choke is now a 1/4 wave away or the same size as one of the dipole legs = 2.59m or 8 and a 1/2 ft.
You can talk worldwide on CB radio,
Some are too far up their own @rse to admit it,
Freebanders happen to know otherwise = test free.

Some of the G call sign holders on 80M are total knobs.

27.781.25 FM
27.555 USB
27.385 LSB
27.315 FM

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Re: Homebrew 1/4 wave copper pipe dipole

Post by Farty » 29 Dec 2018, 20:12

For even better function you can run the coax up the inside of the ground radiator to form a sort of boomerang antenna, a dipole with the appearance of a vertical. Good gain, low radiation angle, very efficient.
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Re: Homebrew 1/4 wave copper pipe dipole

Post by The Collector » 29 Dec 2018, 20:56

108EH002 wrote:
27 Dec 2018, 23:15
After doing some further research I have changed the distance of the rf choke,the rf choke is now a 1/4 wave away or the same size as one of the dipole legs = 2.59m or 8 and a 1/2 ft.

Have you noticed any difference in swr or rf emissions (or whatever you technically call it) etc?

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Re: Homebrew 1/4 wave copper pipe dipole

Post by 108EH002 » 03 Jan 2019, 06:34

After moving the location of the rf choke the swr was really just the same as before Collector.

But = I decided I was going to "turn" the antenna another 90° so it was more directional for east to west.When I got a chance over the festive break,I also altered the inside angle making it slightly bigger than before (closer to horizontal position)about 2 inch/50mm higher up at each end of the legs.I also changed the direction of the rg213 caox/feedline from the original positioning.

The swr readings were now as follows =

1.1 on 26.965
1.0 on 27.500
1.3 on 27.991.25

This might appear to be too strange to be true for most that understand antennas,but this is what the readings were on a Grant 2 V1 and a Lincoln 2 V3 built in meters,the same 2 radios used to take the first swr readings.I am getting good rx across the eu with the short skip,with far less static/white noise/chip pan crackle coming in compared to the Imax thats nearly 30ft up,resulting in stations being received crystal clear compared to being nearly inaudible on the vertical once they are below say a S3.The noise level on my latest Grant 2 is sometimes just the first light on the signal meter,and the meter is not lazy compared to other ones I have used in the past.

Collector = I really can't say if any of the alterations/experimenting I have done is going to massively change this homebrew dipole to be a super dx performer,but you never know eh.

I am just a CB'er with limited radio knowhow or an IQ Zero depending on how you see it,but I do know that this dipole can hear what a £130 vertical CB antenna sometimes CANT,the same as my other homebrew wire dipoles that heard what an 827 and S.G.M. didn't,that were far higher up than the dipoles were ;)
You can talk worldwide on CB radio,
Some are too far up their own @rse to admit it,
Freebanders happen to know otherwise = test free.

Some of the G call sign holders on 80M are total knobs.

27.781.25 FM
27.555 USB
27.385 LSB
27.315 FM

108EH002
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Re: Homebrew 1/4 wave copper pipe dipole

Post by 108EH002 » 27 May 2019, 13:42

Have recently changed the copper pipe dipole into a horizontaĺ position (from being in an inverted v) at 30ft up and the swr is still fine,and I am still getting decent results for what it is.

Got a radio check from someone 15 mile away,and I was as follows,

Imax = S9
1/4 wave c.pipe dipole = S9+30

Will mean nothing to some but plenty to me ;)
You can talk worldwide on CB radio,
Some are too far up their own @rse to admit it,
Freebanders happen to know otherwise = test free.

Some of the G call sign holders on 80M are total knobs.

27.781.25 FM
27.555 USB
27.385 LSB
27.315 FM

108EH002
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Posts: 1632
Joined: 13 Mar 2013, 22:23
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Re: Homebrew 1/4 wave copper pipe dipole

Post by 108EH002 » 07 Jun 2019, 10:20

^^ My mate was in his car 15/20 mile away parked up/static mobile using a Sirio 4000 ^^
You can talk worldwide on CB radio,
Some are too far up their own @rse to admit it,
Freebanders happen to know otherwise = test free.

Some of the G call sign holders on 80M are total knobs.

27.781.25 FM
27.555 USB
27.385 LSB
27.315 FM

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