[Elecraft] K3 if isolation of softrock lite used as panadapter

[Jack Smith]

Thanks - the post was actually captioned 2nd Run on Z10000 Buffer 
Amplifier.

For the K3, the universal model of the Z10000 would be usable and will 
provide around 70 dB isolation, which, when combined with the isolation 
in the K3's internal source follower IF buffer pick-off amplifier should 
be enough to let a Softrock receiver work without interference to the K3.

I've delayed receipt of my K3 until the 2nd receiver issues are sorted 
out, so I can't run tests, but based on the numbers involved (Softrock 
local oscillator output around -40 dBm if my memory is correct) the 
Z10000 and K3 internal isolation in  tandem should be adequate.

A related issue is whether it is necessary/desirable to interpose a 
bandpass filter between the K3's IF output and the Softrock receiver 
input. There's a lot of stuff that comes out the K3's IF output port, 
signals from internal oscillators, etc. I don't have an opinion on 
whether a 300 or 400 KHz wide bandpass filter will be necessary or not. 
Again, that requires some measurements that I can not perform until my 
K3 arrives. Since the Softrock works with an antenna connected to it, I 
suspect that additional filtering won't be required, but it would be 
nice to verify my suspiscion.

I also have a connectorized version of the buffer amplifier, but had not 
decided whether to make it available or not. I use them around my shop 
when I need extra amplification for a particular project.

Jack K8ZOA


rkayakr wrote:
> Stephen
>
> Please comment by Jack Smith K8ZOA on Z10000 interface in topic "K3 SSB
> Strange Behavior".
>
>       Bob
>         KD8CGH
>