Hello,
AIM - To establish network between webpage and Arduino+SIM808
Problem -
I am using a 2G sim which is working fine with my phone but doesn’t work same with with SIM808 module.
The net LED of the Adafruit FONA continuously blinks and I think indicates that the network is not established. I have also tried to update the firmware using SIMcom but the downloading never started.
The following image showes the arduino response:

- Can it be a problem with GSM/GPS signal strength?
- Voltage input ( Using 5V).
Look forward to your response.
Thank you.
You need to have a power source with 4V and 2A current given to the VBAT pins of module.
The network registration can be issue with band settings also.
What is the BAND setting ? Check AT+CBAND?
Thank you for your response.
After entering AT+CBAND. I got the following result.
FONA> A
—> AT+CPAS
<— +CPAS: 2
Unknown
And also I have changed my battery source.
Q. Can this problem associated with the signal strength of GSM antenna?
When you enter AT+CBAND? you should get the band setting name. Why you are getting CPAS responses?
When I entered the AT+CBAND. I got the CPAS response.
I am not sure what is the problem. Kindly help me to fix the problem.
Thanks.
Thats really strange 
Did you enter question mark at the end?
Now it’s working. I think there was problem with the GSM antenna.
Thanks for helping.
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