Some more work on the digimode interface for the FT-857 radio: setting it up
on a real circuit board, to be built into a plastic casing. This time I heard
a strange ticking sound when recording audio from
PI3UTR
but again it seems this clicking sound is a local problem normally filtered out
from the audio path of the radio. When I picked up
PI3UTR on the
Wouxun KG-UVD1P radio I heard the same ticking noise. New respect for the
audio filtering in the FT-857, but things like this make me question the
digimode interface every time I'm testing it.

Radio data interface, The interface in its case
The digimode interface is now finished, but now I need to test it with
real radio signals. I don't have HF capabilities yet, and I did find PSK31
frequencies for 2m (144.610 MHz) and 70cm (432.610 MHz) but nobody
answered a PSK31 CQ on those bands.
Update 2013-08-18:
The whole setup together in a somewhat blurry smartphone picture:

Radio working, PC with fldigi controlling the FT-857 radio sending psk31
And fldigi doesn't mind when I control this remote over the network.