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