How to make phasing line?
 

Hw can I construct 110 deg phasing line for 3.8mhz? 450 ohm window type
ladder line preferred.

This is for 2 dipoles each 121' long and 70' apart. Height above avg
ground 60'. I would like to feed 1 dipole 110 deg out of phase of the
other..

Jay NE2Q

J Koli wrote:
Hw can I construct 110 deg phasing line for 3.8mhz? 450 ohm window type
ladder line preferred.

This is for 2 dipoles each 121' long and 70' apart. Height above avg
ground 60'. I would like to feed 1 dipole 110 deg out of phase of the
other..

Jay NE2Q

110/360 = 0.305 wavelength
0.305 wavelength * 0.95 velocity factor = 0.2897 wavelength in ladder line.

300,000,000 meters/ 1800000 Hz = 166.67 meters free space wavelength.

166.67 * 39.37 / 12 = 546.8 feet.

So, 0.2897 * 546.8 = 155.48 ~ 158.4 feet.

J Koli wrote:
Hw can I construct 110 deg phasing line for 3.8mhz? 450 ohm window type
ladder line preferred.

This is for 2 dipoles each 121' long and 70' apart. Height above avg
ground 60'. I would like to feed 1 dipole 110 deg out of phase of the
other..

You need more than just a 110 degree phasing line if you want the
currents in each dipole to be equal, which is usually the case.
W7EL has information on such in the ARRL Antenna Compendium Vol. 2,
"The Simplest Phased Array Feed System...That Works" Roy might also
have some associated information on his web page at www.eznec.com

If you have EZNEC and use two sources, you will see that those two
feedpoint impedances are widely different so it is no simple matter
to balance the two currents using one feed system.
--
73, Cecil http://www.qsl.net/w5dxp



-----= Posted via Newsfeeds.Com, Uncensored Usenet News =-----
http://www.newsfeeds.com - The #1 Newsgroup Service in the World!
-----== Over 100,000 Newsgroups - 19 Different Servers! =-----

Dave Shrader wrote:

J Koli wrote:

Hw can I construct 110 deg phasing line for 3.8mhz? 450 ohm window type
ladder line preferred.

This is for 2 dipoles each 121' long and 70' apart. Height above avg
ground 60'. I would like to feed 1 dipole 110 deg out of phase of the
other..

Jay NE2Q


110/360 = 0.305 wavelength
0.305 wavelength * 0.95 velocity factor = 0.2897 wavelength in ladder line.

300,000,000 meters/ 1800000 Hz = 166.67 meters free space wavelength.

166.67 * 39.37 / 12 = 546.8 feet.

So, 0.2897 * 546.8 = 155.48 ~ 158.4 feet.

But please note that doesn't balance the currents except by
sheer accident. I'll bet he wants balanced currents.
--
73, Cecil http://www.qsl.net/w5dxp



-----= Posted via Newsfeeds.Com, Uncensored Usenet News =-----
http://www.newsfeeds.com - The #1 Newsgroup Service in the World!
-----== Over 100,000 Newsgroups - 19 Different Servers! =-----

"Dave Shrader" schrieb im Newsbeitrag
news:VLXOb.100682$8H.147484@attbi_s03...
J Koli wrote:
Hw can I construct 110 deg phasing line for 3.8mhz? 450 ohm window type
ladder line preferred.

This is for 2 dipoles each 121' long and 70' apart. Height above avg
ground 60'. I would like to feed 1 dipole 110 deg out of phase of the
other..

Jay NE2Q

110/360 = 0.305 wavelength
0.305 wavelength * 0.95 velocity factor = 0.2897 wavelength in ladder
line.

300,000,000 meters/ 1800000 Hz = 166.67 meters free space wavelength.

166.67 * 39.37 / 12 = 546.8 feet.

So, 0.2897 * 546.8 = 155.48 ~ 158.4 feet.


Not correct!

E1= 1V Z1= 38 - j24.9 Ohm
E2=1v Fi =110deg Z2=9.6 - j 58.2 Ohm

Line Win 450 Vf=0.91 Length= 33.49m = 109.88 feet
Zin = 16.2 + j48.2 ohm

Better: RG 58u/c Length = 21.53m = 70.64 feet
Zin = 20.2 + j 17.5 ohm

or Belden 9258(RG 8x) Vf=0.82 Length=27m= 88.58 feet
Zin = 18.9 + j 17.6 ohm

But, what for is this antenna?

73! Alexander, DL1PBD