[1000mp] Sound Card - FT1000MP

[Ronald Walters]

I have a low level audio out from the sound card homebrew interface that I
currently have connected to the Packet jack on the back of the rig.  Works
great
for all digital modes and allows for front mic input muting when in the
digital modes.

Digital modes I want to try is the MT-63 and SSTV.

My old vintage FT1000MP does not support the Packet mode in USB, only LSB
and FM.

MT-63 on 20 meters is a USB function so I need to utilize a different audio
in to the FT1000MP.

Looks like I have three (3) choices, one being the Audio "Patch" input using
a standard Phono jack, microphone connector front panel and the other is the
DVS input jack, however, that jack has some control function cable
requirements that I am still not sure about there functionality.

Unless I build a new microphone cable to my interface and change from mic to
sound card connector every time I change modes I am thinking of using the
phono input connected to a "Y" connector at the mic out connector at my
interface which has transformer isolators and adjustable resistor network.

My initial concerns are running the two inputs in parallel, that is the
Packet audio in (It only becomes active during PKT selection) and the phone
jack input impedance (load).  I realize that when I elect to use the phone
input I still will need to disconnect the microphone. I am also concerned
about leaving the patch input connected during non digital mode activity and
possible introducing RF feedback or just plain hum.

Before I embark on the re-cabling needed I thought that I asked from the
experienced digital operators probably the safest is a second microphone
front panel connector.  Any thoughts?  I only need a USB audio in since I
key the rig through the CAT interface in all modes.  Any recommendations?

Ron W4LDE