Help with high swr on wire diapole 11 mtrs

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Dragonfly
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Re: Help with high swr on wire diapole 11 mtrs

Post by Dragonfly » 06 May 2016, 10:48

30 degree Inverted V dipole is usually around 2 inches shorter each side than a straight dipole .

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Re: Help with high swr on wire diapole 11 mtrs

Post by original45 » 06 May 2016, 10:59

Thank you will bear this in mind. I tried it between 30&40 degree no real diff in swr.

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Re: Help with high swr on wire diapole 11 mtrs

Post by Buick Mackane » 06 May 2016, 11:01

you sure your SWR meter is accurate?

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Re: Help with high swr on wire diapole 11 mtrs

Post by Dragonfly » 06 May 2016, 11:06

My 2 simple wire dipoles , 1 with a small balun and soldered direct to the coax , the other has no balun and the coax is conected to the wires by a electrical conector .
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Re: Help with high swr on wire diapole 11 mtrs

Post by original45 » 06 May 2016, 11:27

Sorted it guys. The link posted re folding bac wires was it.
Once I unfolded the ends at base of legs and taped them straight ,simular at feed end calibrated swr keyed up on half power 1.5 on channel 20.
So the basics of what I've got works . Just had a radio report well over 10 miles away so I'm nearly their.
Gonna wind a Balun ,cut new wire and re trim as I may be a tad short but will ry and trim it a tad more first now I have no folds back along wire .
Nearly well happy .
Will update once new wire added.
Couldn't have got this far without your input guys. Much appreciate your help,links and advices.

Dragonfly ,is your Balun smaller than 6 coils of coal 5/6" dia ?.

Thanks guys .
The only thing now I'm confused on is my feed . How do you take into account the two wires how they connect re solder to the back of s o plug . As one goes through the 4 holes soldered around back on itself the other soldered to the pin in centre ,surely this will be a miss match on exact equal lengths .

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Re: Help with high swr on wire diapole 11 mtrs

Post by Admiral » 06 May 2016, 11:31

Well done, you now have a half wave dipole that is shittier in performance than a DV27 on a biscuit tin.
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Re: Help with high swr on wire diapole 11 mtrs

Post by Dragonfly » 06 May 2016, 11:45

Shittier but a lot cheaper , Cant remember the last time i came across a DV27 there all in landfill these days .

My ballun is to small really at around 3 ins diamiter , SWR is ok at 4 wats but sky high at 25 wats

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Re: Help with high swr on wire diapole 11 mtrs

Post by Admiral » 06 May 2016, 11:49

Dipoles are for receiving not transmitting, they are the de facto for electrical theory, but in reality below 50mhz they are crap.
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Re: Help with high swr on wire diapole 11 mtrs

Post by Dragonfly » 06 May 2016, 12:04

True , mine are used with my spare sidebanders to listen to SSB and AM ,,My vertical dose all the TX .

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Re: Help with high swr on wire diapole 11 mtrs

Post by Buick Mackane » 06 May 2016, 12:16

Admiral wrote:Well done, you now have a half wave dipole that is shittier in performance than a DV27 on a biscuit tin.
now now how about a bit of encouragement for a wee change ? :D

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Re: Help with high swr on wire diapole 11 mtrs

Post by Dragonfly » 06 May 2016, 12:23

How are Beams constructed , Are they simply 2 Dipoles connected by a poll or is there more to them .

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Re: Help with high swr on wire diapole 11 mtrs

Post by Admiral » 06 May 2016, 12:50

Dragonfly wrote:How are Beams constructed , Are they simply 2 Dipoles connected by a poll or is there more to them .
Yes, beams are a series of dipoles stacked together, some direct, some radiate and some reflect.
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Re: Help with high swr on wire diapole 11 mtrs

Post by Buick Mackane » 09 May 2016, 14:24

Heres my attempt, We'll see what happens when i hook it up :)

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Re: Help with high swr on wire diapole 11 mtrs

Post by kr0ne » 09 May 2016, 14:43

I bought a fancy DIY dipole kit from a well known amateur radio shop but it is terrible. SWR is off the scale and it receives about as well as a piece of damp string.

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Re: Help with high swr on wire diapole 11 mtrs

Post by original45 » 10 May 2016, 10:21

My home made wire seems to work ok. I only manage to get the swr to 1.4 but have had a few decent contacts of over 10 miles away.
I noted swr went up the other day and I'm guessing it was due to wet weather and ground being very wet.

Wire on legs in the inverted v was far better straight with no bends back along wire ,this was critical when I swr mine.
The feed in centre of two legs is only half inch lower than tip of legs too at feed end.
This helped with my swr too.
R X is very good and clear too ,in fact I was very impressed.
Havnt tried it vertical or horizontal.
Tips of legs are only roughly 11" of the ground too in v formation.

Havnt made a Balun yet ,awaiting new coax and I'm going to make a second wire and be more exacting in lengths to see if I can improve on swr next time.

Thanks again chaps for the links , advice and offers .
Nice to see the home made wires too.

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