Homebrew 1:1 Balun
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Homebrew 1:1 Balun
After making my own dipole, I decided to have a go at making a Balun following the instructions here.
http://1.bp.blogspot.com/-Ow6CTxZwYpE/U ... 00/1-1.png
I'm no electronics engineer but looking at the circuit, I read a dead short?
Anyway, I decided to make one and got the bits for about a fiver. I came up with this.
I'm a bit reluctant to put it below my antenna in case I fry my Yaesu. Would someone with a more experienced eye cast their eye over it and tell me if it looks right with the diagram I've used? I've tried to be as accurate as possible and even wound the wires in the position in the diagram.
It's a bit over engineered I suppose but hopefully it will do the job.
Cheers
John
http://1.bp.blogspot.com/-Ow6CTxZwYpE/U ... 00/1-1.png
I'm no electronics engineer but looking at the circuit, I read a dead short?
Anyway, I decided to make one and got the bits for about a fiver. I came up with this.
I'm a bit reluctant to put it below my antenna in case I fry my Yaesu. Would someone with a more experienced eye cast their eye over it and tell me if it looks right with the diagram I've used? I've tried to be as accurate as possible and even wound the wires in the position in the diagram.
It's a bit over engineered I suppose but hopefully it will do the job.
Cheers
John
Rules are for the guidance of wise men and the unswerving obedience of fools.
- cjay
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Re: Homebrew 1:1 Balun
Dead short to DC but nothing like at the frequencies you'll be using and there is nothing wrong with over engineering a piece of kit, it saves you having to climb about repairing it every ten minutesJohnnyLarge wrote:After making my own dipole, I decided to have a go at making a Balun following the instructions here.
http://1.bp.blogspot.com/-Ow6CTxZwYpE/U ... 00/1-1.png
I'm no electronics engineer but looking at the circuit, I read a dead short?
Anyway, I decided to make one and got the bits for about a fiver. I came up with this.
I'm a bit reluctant to put it below my antenna in case I fry my Yaesu. Would someone with a more experienced eye cast their eye over it and tell me if it looks right with the diagram I've used? I've tried to be as accurate as possible and even wound the wires in the position in the diagram.
It's a bit over engineered I suppose but hopefully it will do the job.
Cheers
John
- bigpimp347
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Re: Homebrew 1:1 Balun
this is what a lot of people don't understand..
electrical DC and electrical RF are two different things..
a magnetic loop can use a 9" bit of wire shorted inner to outer with a larger loop around it..
but try to explain it's a DC short and not an RF short and people are stumped..
electrical DC and electrical RF are two different things..
a magnetic loop can use a 9" bit of wire shorted inner to outer with a larger loop around it..
but try to explain it's a DC short and not an RF short and people are stumped..
I want to Die Asleep like my Grandad did,
Unlike his Passengers, Screaming and Shouting.!
Unlike his Passengers, Screaming and Shouting.!
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Re: Homebrew 1:1 Balun
I've bunged it inline and the result is....................SWR over 3 from 1:1 and no perceived signal.
Bugger, I'll check it out again.
Bugger, I'll check it out again.
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Re: Homebrew 1:1 Balun
Lol.
Just checked and found the problem. I've mounted the SO239 incorrectly and not left enough 'neck' for the PL259 to grip to so the connection is not 100%. Two wire to desolder, remount the SO239, resolder and we're good to go.
God, I'm crap!
Just checked and found the problem. I've mounted the SO239 incorrectly and not left enough 'neck' for the PL259 to grip to so the connection is not 100%. Two wire to desolder, remount the SO239, resolder and we're good to go.
God, I'm crap!
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Re: Homebrew 1:1 Balun
No, your experimenting and making your own kit & learning.JohnnyLarge wrote:God, I'm crap!
That's not crap, that's to be applauded.
I like the box it's in & the build - looks good & I hope it works well.
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Re: Homebrew 1:1 Balun
Still not right though. When I connect the pl259's up nice and snug at both ends, I get no signal.
Undo the sleeve and pull the plug out slightly at the radio end so the earth isn't in place and the signal returns.
Must be a wire in the wrong place and it can only be one of two. The location of the green wire connections in the circuit diagram are a bit puzzling.
Mmmmmmmmm.
Thanks for the positive comments so far.
Undo the sleeve and pull the plug out slightly at the radio end so the earth isn't in place and the signal returns.
Must be a wire in the wrong place and it can only be one of two. The location of the green wire connections in the circuit diagram are a bit puzzling.
Mmmmmmmmm.
Thanks for the positive comments so far.
Rules are for the guidance of wise men and the unswerving obedience of fools.
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Re: Homebrew 1:1 Balun
Cracked it!
The middle wire coming off the toroid needed to go to the earth lug on the SO239 and prior to the wind and not to the negative after the wind.
Yep - Sounds complicated to me too but I figured it out and it works.
Whether it will actually improve my station, I'm not 100% sure but for a fiver it's got to be worth a go.
SWR is 1:5, so a little alteration on length on the antenna and it will be sorted.
The middle wire coming off the toroid needed to go to the earth lug on the SO239 and prior to the wind and not to the negative after the wind.
Yep - Sounds complicated to me too but I figured it out and it works.
Whether it will actually improve my station, I'm not 100% sure but for a fiver it's got to be worth a go.
SWR is 1:5, so a little alteration on length on the antenna and it will be sorted.
Rules are for the guidance of wise men and the unswerving obedience of fools.
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Re: Homebrew 1:1 Balun
Job well done.
I will not be commanded, I will not be controlled.
n+1 the formula for working out how many radios you need with n being the current amount.
n+1 the formula for working out how many radios you need with n being the current amount.
- ROTEL240
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Re: Homebrew 1:1 Balun
Nice job John and very well made you will have to let us if you have made any improvements and thanks for the qso the other day.
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Re: Homebrew 1:1 Balun
No problem, Cheers!
Sorry I disappeared but dinner was ready and there was a bit of a circle going on there.
Hopefully I'll hear you again but the PLT/QRM is killing me at home. Hopefully i'll get out one day soon and give the new radio a work out.
Sorry I disappeared but dinner was ready and there was a bit of a circle going on there.
Hopefully I'll hear you again but the PLT/QRM is killing me at home. Hopefully i'll get out one day soon and give the new radio a work out.
Rules are for the guidance of wise men and the unswerving obedience of fools.