Go Back   Worldwide DX Amateur Radio Forums - Ham - CB - HF - VHF - UHF > Citizens Band Related > CB Antennas

Amateur Callsign Lookup
Enter Callsign:

ant. question

Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 01-13-2009, 09:05 PM
Member
iTrader: (0)
 
Join Date: Dec 2008
Posts: 62
stingray is on a distinguished road
Default ant. question



i have a clr2 and an antenna specialists mighty magnum 3.
the clr 2 is supposedly a 5/8 wave. it is 19 feet 10 inches.
how is this possible. the mighty magnum 3 is 18 feet and is half wave.
is hygain lying? i know both have some kind of coil so what makes the magnum stay at half wave and what makes the clr2 5/8 wave?
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
Worldwide Radio Forum
  #2  
Old 01-13-2009, 10:00 PM
Supporting Member
iTrader: (0)
 
Join Date: Apr 2005
Location: Oklahoma
Posts: 3,336
W5LZ is on a distinguished road
Default

Good question. And the answer is where those coils are and what they are there for.
An end fed 1/2 wave antenna has a very high input impedance, something in the neighborhood of 2000 ohms or so. That means that the coil (which should be at the feed point) is an impedance matching device to make that 2000 ohms compatible to that 50 ohms feed line.
That Clr-2, should/could have two coils, or just one which is a combination of both loading coil (to make the thing seem like a 5/8 wave, just shorter) and impdance matching coil to make it's impedance closer to 50 ohms. The location for that loading coil isn't that exacting. It can be located almost anywhere up/down the vertical element. Or, it can be set right on top of that impedance matching coil, making both of them just separate parts of the same, larger, coil.
Make any sense to you?
- 'Doc
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
Reply

Bookmarks


Thread Tools
Display Modes

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
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -7. The time now is 09:09 PM.


Powered by vBulletin®
Copyright ©2000 - 2010, Jelsoft Enterprises Ltd.
Search Engine Optimization by vBSEO 3.3.2
Worldwide Radio Forum