[Elecraft] KPA500 - Rx Attenuation

[Eric Swartz WA6HHQ - Elecraft]

Hi Gary,

This is normal as the KPA500 is designed to attenuate signals the further you go below the 160M band in order to protect the T/R switching diodes from BC band overload. 

73,

Eric  WA6HHQ
elecraft.com
_..._


On Feb 10, 2013, at 5:28 PM, AG0N-3055 <mcduffie at ag0n.net> wrote:

> 
> The spectrum below 160 meters is much more drastic.  Broadcast signals
> suffer lots of signal loss, air-nav signals disappear except for locals,
> and 60KHz WWVB is totally missing, along with all noise of any kind from
> the antenna.  Switching the antenna in and out, had no effect on noise,
> not even a pop is heard in the speaker when switching antennas or
> disconnecting connectors when the amp is in OPER position.  In STBY, all
> sounds normal.
> 
> Generally speaking, the broadcast band could be summed up by saying, the
> lower in frequency you go, the more loss you are going to see when
> switching the amp in and out.  It varies from an S-unit or two, to
> several S-units at the bottom of the band.  Below that, it gets much
> worse.  Only the strongest signals get through in the 250-350KHz range,
> and just about nothing makes it below that.
> 
> These results are also being sent to support.  I don't know if there is
> a pin-diode problem on mine, or if this is to be expected.  I don't like
> it, but can obviously live with it if there's nothing to be fixed.
> 
> Gary
> -- 
>