I'm using the Arduino GSM shield with the built-in antenna. I think I'm going to need an external antenna. Can I just mount a sma connector using the open holes located on the board for a sma connector and plug in an antenna and use it? Will I need to remove the built in antenna? I've tried the two together but don't see much of an improvement in the signal strength.
davidgoth:
Hi,You can use only one SIM. To use another SIM card, you need to design a custom circuit: for example, a proto with another sim tray and switch mechanism, such as a button or a switch. This switch must switch between the two connections of the two SIMs, always with the modem off.
Wow. Have you read the question? It's about ANTENNA and has nothing to do with SIM-cards...
// Per.
Thanks Zapro. I was wondering the same thing myself.
Regarding the antenna, i had a look at the schematics, you need to desolder the PCB-antenna (put a good blob of leaded solder on the connections, heat it up and lift it off the board) Then solder a SMA connector in the vacant hole. Please observe the polarity of the SMA connector, since they exsist in both standard and reverse-polarity.
// Per.
I have a similar question regarding the antennae. I received a shield with an integrated antenna, but think I'll need one with an external antenna. Were you able to replace the integrated antenna with an SMA external connector? If it is relatively simple it may be easier to just replace the antenna rather than return or send for another shield.