GPS is now working well using an external board but when I try to change from using the house WiFI to a 4g dongle it all fails.
The dongle is a HiLink type (Huawei E3372) with a Three Mobile Broadband data sim
The status light indicates its try to establish a link to an LTE cell
When used with a PC it works fine straight off
The SM $G setting screen seems to indicate this is trying to use /dev/ttyUSB0 but this is the port for the GPS
The SIM Card used requires no user or password and links straight to the provider (Three in this case).
Just wondering whether I am missing something simple somewhere

Drivers etc?