Replace XBee chip antenna with u.fl connector?

Wireless & IoT
1

Hi folks, I have three series 1 XBees with the chip antenna. I’ve recently come to need two of them to have the duck antenna to get outside of an enclosure. To save some money I thought I would just replace the chip antenna with the SMD u.fl connector SparkFun sells. I desoldered the chip antenna and cleaned the pads but I notice that all four pads where the u.fl connector go are connected to each other: presumably on the circuit board. I checked one of my other unmodified XBees and this appears to be the case there too.

So, my question is whether something else needs to be done to the board to use the u.fl connector? It would seem to me that having the output signal go to both the ring and the pin of the connector would not make sense. Am I missing something?

Thanks,

Jason

2

I’ve already found the solution to this question, I think:

http://forum.mikrokopter.de/topic-20910.html

The pads are tied to a transformer coil (the balun, I assume) and at this high frequency the coil is quite short, making it look like a dead short across the two pads.