Anonymous wrote:
I'm trying to get started in PSK31. When I connect the audio output
from my receiver to the line input jack on my laptop,
computer-generated RFI gets into the receiver. I bought a Rigblaster
Plus but much to my surprise it doesn't provide any isolation for the
receiver-to-computer connection, just comes with a cable to connect
directly.


I'm also some what of a newbie on the digital modes. On my laptop there
is not Line-In just a Mic-In. What I discovered is that on the ring of
the Mic-In was a +5v to power an electric microphone. So what I ended
up doing was making sure that I only used the Tip and Ground. I also
built my own interface in which I had to put a couple of resistors in
the line to reduce the voltage even more as the mic is a lot more
sensitive then the line in. I also got a couple of 600 ohm 1:1 audio
transformers to isolate it even more. But since you are running a rig
blaster you should have an issue with isolation. If you are using the
Mic-In I would build my own cable with a stereo 1/8th jack and leave the
Ring disconnected.

Hope this helps.

Stephen
VE6CPU