[Top] [All Lists]

Re: [Amps] *** SPAM *** Re: Antenna traps

To: Ian White GM3SEK <>
Subject: Re: [Amps] *** SPAM *** Re: Antenna traps
From: Steve Thompson <>
Date: Fri, 16 Dec 2005 15:27:05 +0000
List-post: <>

Ian White GM3SEK wrote:

> Let's think of two totally generalized impedances, (R1 in series with 
> jX1) and (R2 in series with X2). In this context X1 and X2 can have 
> either sign.
> Now add series elements -X1 and -X2 to cancel both reactances out. We 
> now have resistive impedances R1 and R2, which can be matched with the 
> minimum-Q solution using two elements in one of the L-network 
> configurations.
This is where I started - but you can always add a first element to take 
you to a pure resistance that's nearer your target than (say) R1 is. 
Then, the L match from the new resistance to target will have a lower Q 
than the one from R1 to target and the three elements give you lower Q 
than two.

I think the train of thought can be valid where you can't choose 
whichever of the L match permutations is needed for minimum Q - that's 
the trap I fell in to.

Amps mailing list

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