> 4.2 | Antenna Pad

> The antenna can be soldered to the pad, or attached via contact springs. For proper grounding connect the antenna to the ground plane on the bottom of TC65 which must be connected to the ground plane of the application.
> When you decide to use the antenna pad take into account that the pad has not been intended as antenna reference point (ARP) for the Siemens TC65 type approval. The antenna pad is provided only as an alternative option which can be used, for example, if the recommended Hirose connection does not fit into your antenna design.
> Also, consider that according to the GSM recommendations TS 45.005 and TS 51.010-01 a 50Ω connector is mandatory for type approval measurements. This requires GSM devices with an integral antenna to be temporarily equipped with a suitable connector or a low loss RF cable with adapter.
> Notes on soldering:

> • | To prevent damage to the module and to obtain long-term solder joint properties you are advised to maintain the standards of good engineering practice for soldering.

> • | Be sure to solder the antenna core to the pad and the shielding of the coax cable to the ground plane of the module next to the antenna pad. The direction of the cable is not relevant from the electrical point of view.

> TC65 material properties:
> TC65 PCB: FR4
> Antenna pad: Gold plated pad