I'm not sure how good is the satellite fix with the SkyDemon Mobile (or Third Party devices) when inside the cockpit. 

The aircraft I fly is fitted with an external GPS aerial with a BNC connector in the instrument panel.

Does anyone know how to connect the SkyDemon Mobile (or Third Party device) to a BNC connector in order to get a better signal from the external aerial?

I have seen battery powered re-radiating aerials but I prefer a wired connection to the GPS device via the BNC if this can be done.

Thanks for any tips.

Regards,
Mark