Call Search
     

New to Ham Radio?
My Profile

Community
Articles
Forums
News
Reviews
Friends Remembered
Strays
Survey Question

Operating
Contesting
DX Cluster Spots
Propagation

Resources
Calendar
Classifieds
Ham Exams
Ham Links
List Archives
News Articles
Product Reviews
QSL Managers

Site Info
eHam Help (FAQ)
Support the site
The eHam Team
Advertising Info
Vision Statement
About eHam.net

   Home   Help Search  
Pages: [1]   Go Down
  Print  
Author Topic: Choice of feedline for a bent dipole  (Read 596 times)
KB4UHK
Member

Posts: 5




Ignore
« on: January 07, 2013, 08:19:02 PM »

Basic question. I'm setting up a (nearly) invisible dipole on a second story balcony.. bent dipole (inverted u) hanging out over the bottom of the third story balcony and dangling down.

I'm thinking of running twinlead to the antenna from the transmatch, but I wanted a second opinion about it before I do. Twinlead would be easier to disguise and keep from getting crunched the way I am running it.

Does this sound like a good idea, or should I just stick with coax?
Logged
N4CR
Member

Posts: 1666




Ignore
« Reply #1 on: January 07, 2013, 11:34:28 PM »

If you can keep the twinlead away from the building then it's an excellent feed line.
Logged

73 de N4CR, Phil

We are Coulomb of Borg. Resistance is futile. Voltage, on the other hand, has potential.
WB6BYU
Member

Posts: 13234




Ignore
« Reply #2 on: January 08, 2013, 09:01:52 AM »

Twinlead allows you to load the antenna on different bands.  That's generally
an advantage.  It also means that you don't need to adjust the antenna for
low SWR:  repeated fussing with an invisible antenna to tune it can invite
unwanted attention to the installation.

If you have to run your feedline across the roof and through a metal rain
gutter or downspout, then twinlead isn't a good choice.  It tends to get
more lossy when wet, and the fields extend further around the conductors
than is the case with coax.  So there are some tradeoffs.

For this application, the characteristic impedance of the line isn't as important,
and you can make your own balanced line using a pair of thin wires with a minimum
of insulators between them for minimum visual impact.  I've run a pair of wires
up to 75' with no spacers just by pulling up enough tension on them (using 6" to
12" spacing between wires.)
Logged
Pages: [1]   Go Up
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.11 | SMF © 2006-2009, Simple Machines LLC Valid XHTML 1.0! Valid CSS!