Lock on a specific ARFCN in EC25

Hi every one;
How can I lock on a specific ARFCN (GSM) or EARFCN (UMTS) in Quectel EC25 modem? I can’t find a correct at command in the documents.

Dear Mortezaaliahmadi,
Thanks for your inquiry in Quectel Forums.
Sorry that LTE module cannot lock a specific ARFCN (GSM) or EARFCN (UMTS), just can lock a special cell of LTE, please check the following command. Thanks!


1 Like

Thanks friend…
Is there a module which can lock on ARFCN (GSM) and EARFCN (UMTS)?

Dear Mortezaaliahmadi,
For 2G module, you can use the following command to lock ARFCN. And we have no such AT command to lock EARFCN(UMTS). Thanks!

Thanks again Kyson for the commands. I mean that can you offer me one or some modems for 2G and 3G with ARFCN (EARFCN) lock compatibility? (I have bought Quectel EC25 LTE module)

Dear Mortezaaliahmadi,
For 2G module, you can choose MC60 module. For 3G module, we have no AT command to lock ARFCN, if you still want to choose one, it is better to choose UC200T. If you need to get some samples, please contact our local sales. Thanks!

1 Like

Thank you very much dear Kyson…

This is not directly related to the topic, but it is a follow up to the post by @Kyson above.

When setting “Action” to “1”, is that functionally band locking? It reads as though setting action to 1 would just lock to the LTE EARFCN and would not need the PCI. Please confirm.

The note says the configuration will not be saved into NV. How do you do cell locking in LTE and have it stick after reboot?

Dear Uberdome,
Thanks for your inquiry in Quectel forum.
Please check the following answer to your question. Thanks!
1, Action to 1 just means that enable lock LTE cell through appointed EARFCN, actually not band locking, as you know that one band may include many EARFCN.
2.Yes, correct. The configuration will not be saved into NV. It will take effect after you set it, no need to restart the module. The example in the following already tell you how to lock LTE cell. Please check. Thanks!

I tested the QNWLOCK command, and it appears my firmware may be too old to accept it. I must have received some very old stock. I have a ticket open to get updated firmware, so I will try again when I receive it.

You say there is no need to reboot the modem, but what happens after a power outage? What is the best method to keep LTE Cell locking persistent even after power loss?

Thank you, Chris

Dear Uberdome,
Just as i have said that the setting will not saved into NV, so if the power loss, you may need to set it again by yourself. Please note that it is internal command, we do not recommend customer to use it frequently, only use it when you needed. As you know that if you lock the cell, and when the cell signal lost, the module may cannot register on network successful all the time. So there have no good method to keep it persistent, except you set it by yourself. Thanks!

I understand the limitations of cell locking, we find it necessary when connecting to distant towers and one PCI is uncongested but has a lower signal. I’ll have to think about how to apply the PCI lock after rebooting.

I have the EC25-AF that is being tested right now. I have found it responds with an error if I use “common/lte”, but that “common/4g” works. Is there a different setting I need to have it respond to /lte instead of /4g?

Dear Uberdome,
Please make sure you have fixed to LTE mode before you use common/lte command, and if you want to use common/lte, please do not use common/4g again. The two commands should not be mixed. Thanks!