[Elecraft] Baluns & wires & feeders (oh, my!)

[Karl Larsen]

N2TK, Tony wrote:
> I ask this as a question - Putting baluns or UN-UN back to back checks that
> both have the same ratio and can check efficiency if they are transformers
> such as what is used on beverages. How does this check if it is working well
> as a balun? As an example, a straight piece of coax with ferrite beads on it
> could be treated as one or two baluns back to back. But just checking power
> at the end versus power going in would seem to check the efficiency of the
> coax but not tell you how much, if any RF was on the outside of the shield.
> Please correct me if I am all wet.
>   
    Hi Tony, you missed the question. We assumed the balun's were made 
properly. The task was to measure the loss through them.

73 Karl

> 73,
> N2TK, Tony
>
> -----Original Message-----
> From: elecraft-bounces at mailman.qth.net
> [mailto:elecraft-bounces at mailman.qth.net]On Behalf Of Dave G4AON
> Sent: Saturday, October 07, 2006 2:54 AM
> To: elecraft at mailman.qth.net
> Subject: Re: [Elecraft] Baluns & wires & feeders (oh, my!)
>
> There is a simple way to measure the efficiency of a balun, make two of
> them and connect them "back to back". Measure the power fed to them and
> the corresponding output power. Obviously this doesn't take a mismatched
> antenna into account.
>