On Nov 27, 11:35*am, "Tom, N3IJ" wrote:
I want to interface the audio from the Small Wonder Labs PSK20 to the
mic input in the Toughbook CF27 laptop. The computer has no line
input, and I plan to use the mic input via the port replicator. The
Toughbook reference manual doesn't give any specs for the mic input.
The user manual does contain this caution:

"Use only a monaural condenser microphone (miniature jack). Using
an input source other than a monaural condenser microphone
may not allow audio to be input or may damage the equipment."

Reading suggests that an L pad in the 40-60 dB range is required, but
I would like to narrow this down before experimenting. Any experiences
using the Toughbook on PSK would be helpful.

Thanks, Tom, N3IJ

What I ended up with is an L-pad with 10K in series with the input and
100 across the output. This is supposed to be a 40dB pad. I may need
something in the high 30s instead of 40, because to get a satisfactory
waterfall, I need to max the mic gain in Windows 2K. Tomorrow I'll get
a 5K pot and connect it in series with a 5K resistor in place of the
current 10K resistor. 8-9K might be where I need to be to have the
Windows level control somewhere in the middle of its range.

Thanks to all for the suggestions.

Tom