[Scan-DC] Stacked dipoles

[Rick Hansen]

Bob,

 

If you twist the ends together you get 150 ohms, vs. 75 ohms

 

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Then you can stack two dipoles, hook them in parallel with a phasing stub,
and get 75 ohms. 

 

Here's how to make a gain antenna for 450 Mhz from Coax, stacking them
end-to-end:

http://www.rason.org/Projects/collant/collant.htm

 

Good luck,

 

Rick

 

 

 

 

  _____  

From: scan-dc-bounces at mailman.qth.net
[mailto:scan-dc-bounces at mailman.qth.net] On Behalf Of W4NNG
Sent: Sunday, January 25, 2009 7:18 AM
To: Scan DC
Subject: [Scan-DC] Stacked dipoles

 

At least w/ digital trunking, most of the stuff I'm interested in, is in the
800Mhz band.  

 

Been looking for some cheap indoor homebrew antenna solutions and one
thought was stacked dipoles stuffed in a pvc pipe.   Like the idea of having
it unobtrusivly stuck in the a room coner.  

 

I tested a single 300 ohm twin lead dipole and it worked better then the
whip that came with the -197.    

 

Before I waste too  much time on the next step, thought I check and see if
anyone has any thoughts on what kind of matching gotcha's happen when you
try to stack a bunch of them?

 

Thanks for any thoughts,

 

Bob

 

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