[Elecraft] P3 ghost signal?

[Wayne Burdick]

Hi Vidi,

This is normal.

Most receivers have out-of-band receive responses that are created by  
high-order harmonics of the VFO, BFO, and other signal sources. The K3  
is no exception, since it's a down-conversion superhet using high- 
level injection. Generally these responses will be inaudible because  
they never appear right at the I.F. (~8.215 MHz in the case of the K3).

The P3, which gets its signal *before* the crystal filters, can  
display a much wider I.F. bandwidth. So some receive responses you'd  
never hear may show up in the P3's passband. In theory, we could map  
these out at the P3, but it's a complex equation involving the  
frequencies of the signal sources, crystal filter center frequencies,  
selected sideband, passband center pitch, etc.

73,
Wayne
N6KR


Vidi wrote:

> I noticed that on 17.6792mHz there is a strange ghost signal visible  
> on the P3.    As I tune over it, it moves in the opposite direction  
> to VFO dialing direction!  I turned everything off in the shack and  
> also selected the dummy load but it is still there.  This ghost  
> signal is not audible on the K3 and only shows up as a 'signal on  
> the P3.  I wonder if it is only my P3 that does this.
>
> Vidi - ZS1EL