[Elecraft] K3 power reduction due to high SWR

[Geoffrey Mackenzie-Kennedy]

Vic,

Before you write off "truly balanced tuners" in favour of the T-network + 
balun <g>, it would be interesting to measure and compare the current in 
each wire of the feeder (while transmitting a carrier) when using the 
Matchbox and then the T-network + balun?

73,
Geoff
LX2AO


On April 05, 2012 18:28 +0200, Vic K2VCO wrote:


<snip>

> But here is the surprising part: I expected that the Matchbox would 
> provide better
> balance, which would reduce radiation and pickup from the feedline. To 
> test this, I
> coupled a grid-dip oscillator to the feedline about 20 feet from the 
> tuner.
>
> To my great surprise, the signal from the oscillator was much weaker with 
> the T-network +
> balun than with the Matchbox!
>
> Signals the same, 'noise' weaker. So much for the need for 'truly 
> balanced' tuners!