3DR Radio + MinimOSD = no MAVlink :-(

Hi all, hope somebody can shed a light on my problem.
I have been flying 2 quads and a Skywalker for 1,5 years and many hundreds of flights with APMs and never had a problem. This time though, I can’t get my head around what is going on.
I have replaced a normal APM 2.6 with HobbyKing’s HKPilot Mega Mini which thanks to its small form factor fits my XuGong-10 frame nicely. I use the standard Y-cable to split telemetry across my MinimOSD and the 3DR Radio air module. But it doesn’t work when I connect both!

Scenarios tested:

  1. Only 3DR Radio connected
    [ul][li]Solid telemetry connection to both Mission Planner and DroidPlanner2. Link stats show no dropped packets[/li][/ul]
  2. Only MinimOSD connected
    [ul][li]Solid OSD data streams, everything working normally[/li][/ul]
  3. Both connected
    [ul][li]MinimOSD displays ‘No mav data!’[/li]
    [li]3DR Radio has green solid light, no blinking red light (link ok, no data)[/li][/ul]

When I have both connected, the moment I unplug one, the other starts working right away. After migrating to the HKPilot Mega Mini I have never used the dual setup and therefore I am unsure if this is due to hardware or software differences.
I already thought it could be a brownout/power problem but adding a 5V UBEC for separate power doesn’t fix it.

HKPilot Mega Mini (APM 2.5.2) running APM:Copter 3.1.5
MinimOSD running minimosd-extra 2.4-r726
3DR Radio 915 MHz module running SiK firmware 1.9

[nc]HKPilot Mega Mini[/nc]

I know the forum is sponsored by 3DRobotics, but why should questions be limited to their products only? I am not asking for customer support from 3DR, I am just posting in an open community and this is a very logical place.

BTW, I posted the same question on DIYDrones and already have my answer: diydrones.com/forum/topics/3dr-r … no-mavlink

Please read the forum rules, section 7! The hardware subforum is the official 3DR hardware support forum in which 3DR support technicians answer questions. Because of this, clone questions are not allowed here.

Besides, arducopter.com is not an open community. It’s a dedicated support forum. The open community is DIYD.