[Elecraft] SWR bridge in KAT

[Bob - AG5Q]

My thanks to Leo and others who responded about my SWR bridge question.

Finding out it's based on the Bruene circuit is helpful. A simplified
drawing of that circuit is shown in the Antenna Handbook.  I'm still trying
to figure out a Spice model for it.

73/ Bob - AG5Q

----- Original Message -----
From: "Leo Starrenburg PA5LS" <pa5ls@home.nl>
To: "Bob - AG5Q" <AG5Q@attbi.com>
Sent: Sunday, January 19, 2003 2:49 PM
Subject: Re: [Elecraft] SWR bridge in KAT


> Hi Bob, this is what I received from Tom N0SS on the subject:
>
> The reason Wayne has you add 20% to the REFL pot resistance is due to an
> abberation he (and KI6WI, if I recall) found in the basic design of the
> Breune-style wattmeter circuit Elecraft uses. They found that the REFL
> voltage level (returned my the bridge) was reduced somewhat by resistor
> (R1). The 20% increase in the value of R4 is to account for this
inaccuracy.
>
> Hope it helps,
>
> 73' Leo.
>
>
> > Can someone please direct me to info on the theory behind the SWR bridge
> > used in the KAT2 (and KAT1)?
> >
>
>
>