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Homemade wire di-pole antenna

Posted: 23 May 2019, 20:31
by hdjmings1
Hi ive been making my own di-pole antenna, like the one attached..... i first used household mains earth cable like you would find on heating pipes i got a 1.5swr but could not hear anyone on bands, im going to change it to spare coax i had, could it be the earth cable the reason i cannot hear anyone or could it be just no one on?

Re: Homemade wire di-pole antenna

Posted: 23 May 2019, 21:49
by ch25
No wonder you couldn't hear anybody when you are using horizontal polarized antenna. It is circa 25db (4s units) of attenuation for vertical polarized signals.
Chris

Re: Homemade wire di-pole antenna

Posted: 23 May 2019, 21:49
by Buick Mackane
I'd stick with the earth cable, Thicker wire gives better bandwidth, There really isn't a great number of people on FM CB These days, Plus don't forget that horizontal dipoles are directional, Which might be part of the problem, If the breakers in your area are on the deaf sides of your dipole,

And as lemmy above says most people using CB Use vertical antennas, So there will be a fair amount of loss when using a horizontal antenna

Re: Homemade wire di-pole antenna

Posted: 23 May 2019, 22:04
by hdjmings1
Thank you for your replies, this is in the loft, so best bet would be to hang it vertically in the loft?

Re: Homemade wire di-pole antenna

Posted: 23 May 2019, 22:09
by Buick Mackane
hdjmings1 wrote: 23 May 2019, 22:04 Thank you for your replies, this is in the loft, so best bet would be to hang it vertically in the loft?
Best bet would be an outside aerial

Re: Homemade wire di-pole antenna

Posted: 23 May 2019, 22:17
by hdjmings1
Buick Mackane wrote: 23 May 2019, 22:09
hdjmings1 wrote: 23 May 2019, 22:04 Thank you for your replies, this is in the loft, so best bet would be to hang it vertically in the loft?
Best bet would be an outside aerial
Lol i would love one but cant get one up at the moment, along with lack of funds lol

Re: Homemade wire di-pole antenna

Posted: 23 May 2019, 22:20
by Buick Mackane
Ok, Well some form of vertical antenna in the loft would probably yield better results, Whether its a dipole or something else, Plenty homebrew antenna info online,

Re: Homemade wire di-pole antenna

Posted: 24 May 2019, 08:23
by Auldgeek
Buick Mackane wrote: 23 May 2019, 22:09
Best bet would be an outside aerial
:wtf:
:think:
Great advice that :thumbup:

Re: Homemade wire di-pole antenna

Posted: 24 May 2019, 08:33
by Auldgeek
hdjmings1 wrote: 23 May 2019, 22:17
Buick Mackane wrote: 23 May 2019, 22:09
hdjmings1 wrote: 23 May 2019, 22:04 Thank you for your replies, this is in the loft, so best bet would be to hang it vertically in the loft?
Best bet would be an outside aerial
Lol i would love one but cant get one up at the moment, along with lack of funds lol
As a compromise, use 1/4 vertical radiator and 4 matching 1/4 connected to the outer braid and laid horizontally. Probably best to make up an rf choke for where the feed point is.
Effectively, a vertical ground plane.

Outside is always best, even a wire antenna such as a TL2T hung vertically will yield better results than inside.

Re: Homemade wire di-pole antenna

Posted: 01 Jun 2019, 09:03
by 108EH002
hdjmings1 wrote: 23 May 2019, 20:31 Hi ive been making my own di-pole antenna, like the one attached..... i first used household mains earth cable like you would find on heating pipes i got a 1.5swr but could not hear anyone on bands, im going to change it to spare coax i had, could it be the earth cable the reason i cannot hear anyone or could it be just no one on?
If you were using this antenna with the Lincoln on 27.555 Usb and heard nothing at all,then the band must have been dead quiet.

I am using a 1/4 wave horizontal dipole made from 15mm copper pipe that is 30ft up,suspended from the attic beams with fishing line,and it hears some of the locals better (same signal less static) on fm than my Imax that sits 28ft off the ground.

The skip has been banging in the last week on 27.555 Usb on my homebrew c.pipe dipole,and still is as I type.

Maybe worth another listen before you dismiss it as a poor antenna,more like there were probably no locals on and the skip just wasn't there,as the swr was fine.

My dipole is facing to the south east at present ;)

Re: Homemade wire di-pole antenna

Posted: 01 Jun 2019, 09:50
by 108EH002
ch25 wrote: 23 May 2019, 21:49 No wonder you couldn't hear anybody when you are using horizontal polarized antenna. It is circa 25db (4s units) of attenuation for vertical polarized signals.
Chris
Unless he was trying to dx on Ssb,the band might have been quiet,and maybe none of his locals were on Uk40fm.

What is the db gain using a horizontal dipole talking to someone on a beam,compared to using a vertical to talk to someone using a beam ? = conditions and location play a massive part regardless of the equipment being used imo.

Re: Homemade wire di-pole antenna

Posted: 03 Jun 2019, 02:39
by 108EH002
hdjmings1 wrote: 23 May 2019, 20:31 Hi ive been making my own di-pole antenna, like the one attached..... i first used household mains earth cable like you would find on heating pipes i got a 1.5swr but could not hear anyone on bands, im going to change it to spare coax i had, could it be the earth cable the reason i cannot hear anyone or could it be just no one on?
Might sound daft but is the local/dx button pushed in ?

Just that a local ham "returned" a few month ago and he was saying people should have been stronger to him (new Imax well up) ? He soon heard "further/better" when I told him to check this button was in the dx position,I doubt it is but just incase,you never know ;)

Re: Homemade wire di-pole antenna

Posted: 07 Jun 2019, 09:04
by 108EH002
ch25 wrote: 23 May 2019, 21:49 No wonder you couldn't hear anybody when you are using horizontal polarized antenna. It is circa 25db (4s units) of attenuation for vertical polarized signals.
Chris
A few year back my mate who is an amateur was on a 706mk1 at 100w through an Imax 35ft up,and was the same signal as a local amateur 1/2 a mile away running a top of the range hf set at 100w into a £2000 beam/tower.

My mate shouted straight after the other local finished and both were 5/7 into China (contacts on qrz)

My mates radio was £300 secondhand and new Imax £100, other ops set up £10,000 = one was vertical one polarised horizontal = please explain your theory against this fact,other than you can get different antenna giving the same results regardless of polarisation,or how far away the other contacts are.

Last week I was talking to a mate using an Imax 28ft up,and he was roughly 15/20 mile away in his car,using a Sirio 4000 parked stationary and I was a S9,but with my homebrew 15mm copper pipe dipole sitting horizontal I was S9 +30,running the same radio/power at his vertical 4000.

The antenna theory used can only work when there is free open space (imo) between each other for groundwave,and can't be right when obstructive things lie in the way of each other's signal's paths,skips unexplainable even to those who strive to know.

Re: Homemade wire di-pole antenna

Posted: 28 Jun 2019, 00:33
by hdjmings1
Yes i think the band was dead last week i spoke to south france on that home made copper wire (10mm mains earth cable) with around 80/90W and report was S9+30, he was S5/S9 but i also had a bit of static
So worked well, over last week ive been hearing a lot of french stations on the band (27.555)