caramoan tour package

caramoan tour package

Author Topic: swr problem  (Read 1444 times)

Offline AaaeeE

  • CR2032 Battery
  • **
  • Posts: 16
  • Pogi/Ganda Points: 0
  • Gender: Male
  • "If other's can do, why cant i"
swr problem
« on: September 01, 2008, 11:45:31 PM »
gud eve po.... pwd po nyo ba ako 2lungan sa pag.kuha nang swr of yagi-uda antenna using this parameter
and may nakapagsabi kc sakin may software daw para sa swr reading....

Fc = 79mhz
lambda = 3.6 meter

lambda/2 for driven element = 1.8 meter or in feet 5.91 ft.
for reflector element length = 6.496ft
for director element lenght = 5.31ft
spacing from reflector to driven element = 2.126ft
spacing from driven to director1 element = 1.89ft
spacing from director1 to director2 element = 2.126ft
spacing from director2 to director3 element = 2.36ft
"debale po apat ung element ko d pa kasali ung driven element"

salamat po.... wala kc ako device or equipment to read the swr....maintindihan
sana po nyo ako.....





Philippine Electronics Forum

swr problem
« on: September 01, 2008, 11:45:31 PM »

Offline reianjim

  • CR2032 Battery
  • **
  • Posts: 7
  • Pogi/Ganda Points: 0
Re: swr problem
« Reply #1 on: September 07, 2008, 12:27:41 AM »
what a question...

swr = (r+1)/(r-1);

where r is reflection coefficient....

Philippine Electronics Forum

Re: swr problem
« Reply #1 on: September 07, 2008, 12:27:41 AM »

Offline AaaeeE

  • CR2032 Battery
  • **
  • Posts: 16
  • Pogi/Ganda Points: 0
  • Gender: Male
  • "If other's can do, why cant i"
Re: swr problem
« Reply #2 on: September 07, 2008, 03:34:00 PM »

swr = (r+1)/(r-1);

where r is reflection coefficient....

d kc madali kunin ung reflection coefficient, lalo na pag wla kang equipment or device..

paano ba kunin ung reflection coefficient?



"may mga tao talaga magaling mag.salita, pero wlang gawa..." ;D

Philippine Electronics Forum

Re: swr problem
« Reply #2 on: September 07, 2008, 03:34:00 PM »

Offline Shey

  • Administrator
  • Gas Turbine
  • *****
  • Posts: 2004
  • Pogi/Ganda Points: 154
  • Gender: Female
  • "E tangi ana koe Hine e hine, E hine e Hoki maira"
    • Elab.PH
Re: swr problem
« Reply #3 on: September 07, 2008, 03:46:41 PM »
mas madali i-measure mo na lang yung Vmax at Vmin along the transmission line using an analog voltmeter tapos divide mo yan.. Vmax divide by Vmin is SWR..

what you need to do is "run" the voltmeter along the length of your transmission line and measure the maximum and minimum voltage..
I wish for this night-time to last for a lifetime
The darkness around me
Shores of a solar sea
Oh how I wish to go down with the sun
Sleeping
Weeping
With you

I walk alone
Every step I take
I walk alone
My winter storm
Holding me awake
It’s never gone

I fear that soon you'll reveal
Your dangerous mind
As your true colours show
A dangerous sign

Philippine Electronics Forum

Re: swr problem
« Reply #3 on: September 07, 2008, 03:46:41 PM »

Offline Shey

  • Administrator
  • Gas Turbine
  • *****
  • Posts: 2004
  • Pogi/Ganda Points: 154
  • Gender: Female
  • "E tangi ana koe Hine e hine, E hine e Hoki maira"
    • Elab.PH
Re: swr problem
« Reply #4 on: September 07, 2008, 03:54:49 PM »
gud eve po.... pwd po nyo ba ako 2lungan sa pag.kuha nang swr of yagi-uda antenna using this parameter
and may nakapagsabi kc sakin may software daw para sa swr reading....

Fc = 79mhz
lambda = 3.6 meter

lambda/2 for driven element = 1.8 meter or in feet 5.91 ft.
for reflector element length = 6.496ft
for director element lenght = 5.31ft
spacing from reflector to driven element = 2.126ft
spacing from driven to director1 element = 1.89ft
spacing from director1 to director2 element = 2.126ft
spacing from director2 to director3 element = 2.36ft
"debale po apat ung element ko d pa kasali ung driven element"

salamat po.... wala kc ako device or equipment to read the swr....maintindihan
sana po nyo ako.....


i am not aware of any software that can compute the SWR of Yagi-Uda antenna.. baka naman "Antenna Impedance" ang pinapahanap kasi when you talk about SWR kinconsider natin diyan yung impedance ng transmission line and sa example mo hindi mo naman nilagay yung impedance ng transmission line..
I wish for this night-time to last for a lifetime
The darkness around me
Shores of a solar sea
Oh how I wish to go down with the sun
Sleeping
Weeping
With you

I walk alone
Every step I take
I walk alone
My winter storm
Holding me awake
It’s never gone

I fear that soon you'll reveal
Your dangerous mind
As your true colours show
A dangerous sign

Philippine Electronics Forum

Re: swr problem
« Reply #4 on: September 07, 2008, 03:54:49 PM »

Offline ef - el - ay - pee

  • Lead Acid Battery
  • *******
  • Posts: 680
  • Pogi/Ganda Points: 34
  • Gender: Male
  • Regrets, I have a few...
    • The Taste Bytes Food Blog
Re: swr problem
« Reply #5 on: September 07, 2008, 06:49:42 PM »
tingnan ko lang yung website ng ansoft designer....kasi yun yung gamit kong pangsimulate ng transmission lines ko eh...
"Engineers are the Oompah-Loompahs of Science" - Dr. Sheldon Lee Cooper

Offline gie62

  • Lead Acid Battery
  • *******
  • Posts: 798
  • Pogi/Ganda Points: 56
  • Gender: Male
Re: swr problem
« Reply #6 on: September 07, 2008, 07:14:52 PM »
manghiram ka na lang ng swr meter.

Offline zer0w1ng

  • Technical People
  • Gas Turbine
  • *****
  • Posts: 2179
  • Pogi/Ganda Points: 305
  • Gender: Male
  • Enter any 11-digit prime number to continue...
    • The Cebuano Geek
Re: swr problem
« Reply #7 on: September 08, 2008, 09:02:55 AM »
You could simulate the antenna using NEC (Numerical Electromagnetic Code) simulator.
This software is free and many yagi-uda samples there.
This will give S11 as result which is directly related to SWR.

Download it here http://www.si-list.net/swindex.html .
The Cebuano Geek

Philippine Electronics Forum

Re: swr problem
« Reply #7 on: September 08, 2008, 09:02:55 AM »

 

Privacy Policy

Contact Us: elabph@yahoo.com