NEO-M9N u.FL Module Antenna

GPS/GNSS Development Boards
1

Hello!

I was wondering if it is possible to install a passive ceramic patch antenna to the Sparkfun NEO-M9N u.FL board. According to the schematics and the pictures shown on the product page, the module incorporates a DC bias for active antennas.

Maybe someone is able to tell me if connecting a passive antenna would do any harm (to either the module or the antenna). Could it be, that the LNA_EN pin disconnects the VCC_RF output when it is activated (logic high)? But as far as I understand this (see ublox datasheet), the LNA_EN just disconnects the internal LNA (and only the LNA) when an active antenna is used.

Thanks,

Vulpecula

2

Hello @Vulpecula,

Please give it a try. Connecting a passive antenna should work OK. There is a protection resistor (R14) which will limit the current if required. If you see satellites, then you know its working. :wink:

You can disable the antenna power if required by removing FB1 (or R14). But it does mean getting the soldering iron out…

I hope this helps!

Paul