[Top] [All Lists]

Re: [TowerTalk] Using Stubs to Reject Harmonics

To: "Tower and HF antenna construction topics." <>
Subject: Re: [TowerTalk] Using Stubs to Reject Harmonics
From: "Paul Christensen" <>
Reply-to: "Tower and HF antenna construction topics." <>
Date: Tue, 2 Feb 2010 20:23:31 -0500
List-post: <">>
> Which is why W2VJN's stub cookbook shows some interesting behavior
> with 1/8 wave connecting lines <G>.

Using TLW a while back, I was modeling a 1/8-wave line and it looks like no 
matter what the termination Z at the end of 1/8-wave line, the Z seen at the 
transmitter is always the line Zo. Depending on whether the line is open, a 
short, or somewhere in between, the magnitude of reactance varies greatly as 
does the line SWR, but the Z seen by the transmitter will always be fixed at 

Hypothetically, a length of say...RG-58 in odd multiples of a 1/8-wave would 
make a great dummy load on paper with exceptionally high return loss when 
the termination is either a short or open.  However, I'm not sure how 
various transmitters would take to a Z of 50 ohms where the reactance 
component radically changes between an open or shorted termination but the 
power dissipating resistance portion is only a few ohms.

Paul, W9AC 


TowerTalk mailing list

<Prev in Thread] Current Thread [Next in Thread>