TV Fool  

Go Back   TV Fool > Over The Air Services > Special Topics > Antennas

Notices

Reply
 
Thread Tools
Old 13-Nov-2013, 1:26 AM   #1
davidkjohnson
Junior Member
 
Join Date: Nov 2013
Posts: 2
Combining two Antennas - Balun Polarity

When combining the two antennas do you reverse the leads on one at the balun on the antenna so they are in series or do you keep them the same. Does this matter if they are pointing in the same direction or offset by 90 degrees?
I think I am going to reverse the leads on one and see what happens.
davidkjohnson is offline   Reply With Quote
Old 13-Nov-2013, 2:37 AM   #2
GroundUrMast
Moderator
 
GroundUrMast's Avatar
 
Join Date: Oct 2010
Location: Greater Seattle Area
Posts: 4,738
Are the two antennas identical?

What make/model are they?

What type of combiner are you proposing to use (make/model)?
__________________
If the well is dry and you don't see rain on the horizon, you'll need to dig the hole deeper. (If the antenna can't get the job done, an amp won't fix it.)

(Please direct account activation inquiries to 'admin')
GroundUrMast is offline   Reply With Quote
Old 13-Nov-2013, 1:15 PM   #3
davidkjohnson
Junior Member
 
Join Date: Nov 2013
Posts: 2
combineing antennas

Thank you for responding.

I currently have two identical generic yagis; they are vertically stacked approximately 1 meter apart. I may replace them with name brands if I can prove they will improve a reasonably good reception. I am using an RCA splitter reversed to combine them. They are grounded from the shell of the splitter. I have identical lengths of RG6 from the antennas to the splitter/combiner. I have them aimed 90 degrees from each other to pick-up stations in two large sources. I run RG6 from the combiner to the television. On an average day I will get all the LOS channels plus some unlisted channels. Occasionally I lose some of the more distant channels and would like to reduce those occasions. I am also considering two more yagis to point opposite to the existing ones to cover some fringe are locations.

I am interested in your thoughts.
cheers
davidkjohnson is offline   Reply With Quote
Old 13-Nov-2013, 5:27 PM   #4
GroundUrMast
Moderator
 
GroundUrMast's Avatar
 
Join Date: Oct 2010
Location: Greater Seattle Area
Posts: 4,738
To answer your question re. balun polarity, the signals need to combine in-phase. Reversing one balun will result in less gain.

If you look at commercial antennas, you'll notice that they usually use open wire connections between elements that are ganged together. This is efficient (less loss). However, the diameter of the wire and space between wires determines the characteristic impedance of the transmission line formed. The 'phasing lines' must be the correct impedance to be able to act as RF transformers. If you get it wrong, the RF will not be coupled efficiently.

Some folks find that antenna location makes more difference than 2 or 3 dB of antenna gain.
__________________
If the well is dry and you don't see rain on the horizon, you'll need to dig the hole deeper. (If the antenna can't get the job done, an amp won't fix it.)

(Please direct account activation inquiries to 'admin')
GroundUrMast is offline   Reply With Quote
Reply

Bookmarks

Go Back   TV Fool > Over The Air Services > Special Topics > Antennas


Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off




All times are GMT. The time now is 7:13 AM.


Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
Copyright © TV Fool, LLC