Hi,
Recently I bought one of your GSM shield, but it had a defect. When plugged, I could send AT commands to the module and communicate with the SIM900, but I could not get connected to an operator. The signal was very weak. I tried different Sim Card and operators, but it could never get connected. After testing the conductivity of the antenna circuit, I found that the small surface mount antenna connector was solder incorrectly. It was reversed and the ground was now linked to the sim900 antenna output pin. I soldered it back on the right side, but the damage were already made. Because it was soldered to the ground, the antenna output made a short-circuit and broke the sim900 antenna output. I really needed this module for a project... Do you have a solution for me?
No registration to the network 2
Re: No registration to the network 2
Dear friend,
Sincerely sorry for this inconvenience, but the most important thing I need to point out is all our products have been tested before shipped out. The problem probably have occurred in the course of transit, which is out of our control. But we are serious seller, we do not escape any problem from our customers', we will do whatever we can do for our customers. I hope I can solve your problem together with you.
According to your question, you said that you found a small surface mount antenna connector was solder incorrectly, could you please send me the photos? I need to confirm whether the connector was solder correctly or not before we sent the items, so please send the photos of GPRS which you haven't soldered.
I also need the photos of GPRS which you soldered by yourself.
Waiting your reply.
Best regards.
Sincerely sorry for this inconvenience, but the most important thing I need to point out is all our products have been tested before shipped out. The problem probably have occurred in the course of transit, which is out of our control. But we are serious seller, we do not escape any problem from our customers', we will do whatever we can do for our customers. I hope I can solve your problem together with you.
According to your question, you said that you found a small surface mount antenna connector was solder incorrectly, could you please send me the photos? I need to confirm whether the connector was solder correctly or not before we sent the items, so please send the photos of GPRS which you haven't soldered.
I also need the photos of GPRS which you soldered by yourself.
Waiting your reply.
Best regards.
Re: No registration to the network 2
I highly doubt that during transit someone unsolder and then re soldered the connector backward.
Unfortunately, I haven't took a picture of the Board before the repair, because I wasn't sure it was the problem. The only thing I can give you is a picture of the repair I made. Next time I get a new product, I'll be sure to take picture of it in case it doesn't work.
Unfortunately, I haven't took a picture of the Board before the repair, because I wasn't sure it was the problem. The only thing I can give you is a picture of the repair I made. Next time I get a new product, I'll be sure to take picture of it in case it doesn't work.
Re: No registration to the network 2
Dear friend,
Thank you for your kindly understanding that the problem probably had occured during transit.
And I can understand that you haven't took the pictures when you receive the items.
You can send the photos of the repair you made to our customer service, they will contact you.
Wish you a nice day.
Best regards.
Thank you for your kindly understanding that the problem probably had occured during transit.
And I can understand that you haven't took the pictures when you receive the items.
You can send the photos of the repair you made to our customer service, they will contact you.
Wish you a nice day.
Best regards.
Re: No registration to the network 2
Hi,
Sorry for this delayed answer. I was away for a while. Here's a picture of the repair I made. Has you can see, I rotated the connector 180 degree. When I received the board, the external shield of the coax pin (that is now on top of the picture) was connected to the signal trace. Because the side of this connector are also connected to the ground, it had put the signal trace to the ground and damaged the antenna output.
In this picture, the signal trace is now connected to the center of the coax connector.
Sorry for this delayed answer. I was away for a while. Here's a picture of the repair I made. Has you can see, I rotated the connector 180 degree. When I received the board, the external shield of the coax pin (that is now on top of the picture) was connected to the signal trace. Because the side of this connector are also connected to the ground, it had put the signal trace to the ground and damaged the antenna output.
In this picture, the signal trace is now connected to the center of the coax connector.
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hotkebab99
- Posts: 15
- Joined: Tue Jun 24, 2014 12:53 am
Re: No registration to the network 2
Hello,
I had the same problem, I repaired my shield by doing what I say in the "SIM900 - No registration to network" topic.
And my shield is working now...
I had the same problem, I repaired my shield by doing what I say in the "SIM900 - No registration to network" topic.
And my shield is working now...
Re: No registration to the network 2
You mean your connector was soldered backward?hotkebab99 wrote:Hello,
I had the same problem, I repaired my shield by doing what I say in the "SIM900 - No registration to network" topic.
And my shield is working now...
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hotkebab99
- Posts: 15
- Joined: Tue Jun 24, 2014 12:53 am
Re: No registration to the network 2
Yes, that's it. I have removed it (but broken it - too small) and soldered wires (look at the photo in my topic).ma.seguin wrote:You mean your connector was soldered backward?hotkebab99 wrote:Hello,
I had the same problem, I repaired my shield by doing what I say in the "SIM900 - No registration to network" topic.
And my shield is working now...
Re: No registration to the network 2
Wow! What a patch work.
Mine still isn't able to get register with my SIMCard. I tried with a friend who also bought a SIM900 shield, but from another compagny. He was able to get connected to a network with my board, but he had a very bad signal strength compare to his board that wasn't damage from the short. I still suspect that this mistake damage the antenna output.
I'll just have to write this review on EBAY. Both of us had defect boards....
Mine still isn't able to get register with my SIMCard. I tried with a friend who also bought a SIM900 shield, but from another compagny. He was able to get connected to a network with my board, but he had a very bad signal strength compare to his board that wasn't damage from the short. I still suspect that this mistake damage the antenna output.
I'll just have to write this review on EBAY. Both of us had defect boards....
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Davidperez
- Posts: 1
- Joined: Mon Jan 03, 2022 8:53 pm
Re: No registration to the network 2
If you see the 'not registered on network' error on your device, it means your SIM card can't connect to your carrier's network. You will likely ...Real Life Blog