Problems forwarding MAVLink from MP to tablet via COM port [SOLVED]

I am in need of some guidance how to approach/ fix a connection resp. forwarding issue.

I have a working vehicle connection from SITL (or Pixhawk hardware) to Mission Planner (v. 1.3.62), running on a laptop, via tcp.

Now I am trying to add and connect a (Windows) tablet into the system, which is also running Mission Planner (same version).

Desired setup
For this, I want to forward MAVLink packets out from Mission Planner (laptop) to Mission Planner (tablet), by using SerialOutput - MAVLink.

What works
I can successfully connect via the MP instance on the laptop - but only as long as this is done via tcp (and the tablet is on the same wifi network as the laptop).

What does not work
In the field though, I need this to work via a 3DR radio modem.
However, when trying to forward MAVLink via the COM port of the radio modem connected to the laptop (at the appropriate baud rate, with write access permitted), I am unable to connect to this link from Mission Planner (tablet).
(The SerialOutput (from the laptop) seems active as such; the radios seem correctly configured (green LED is on) and are happily blinking orange when trying to connect.)
On trying to connect MP via the radio modem on the tablet: “Error - No Heartbeat Packets Received”

If I am not mistaken, this connection approach should be possible as such. What must be done to get a successful connection?

Thanks in advance for your inputs!

Had been at this for some time and was stuck (which is why I wrote), but just now seem to have found the culprit…

I finally noticed that the Device Manager on the tablet showed two serial ports, and thus far in trying to connect, I erroneously was focused on (and trying to connect via) "Communications Port (COM1), seeing that there was only one radio connected.
Ended up trying the other one “USB Serial Port (COM3)” - and was connected…

im glad you figured it out. and glad to hear of a more advanced use case :slight_smile: