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Unlocking a Novatel Merlin U530 under Linux

Or another reason why I am glad that I don't use 3 anymore.

I should have posted this some time ago, but forgot and so it has been sitting in my Drivel drafts folder for a bit.

You might want to try these instructions under windows too, if you get a dud unlock. Just use another terminal emulator instead of minicom.

Skip the history and read how to unlock it

I recently switched from 3 mobile to virgin for my UMTS data. I already had a Novatel Merlin U530 card from three. The card isn't fantastic but it works pretty well at upto 384/64Kbps which is good enough for mail and feed reading (my main 2 activities on the train) or ssh.

When trying to get the card unlocked, 3 was less than helpful initially, which is pretty normal for them. Initially the operator told me that my card could not be unlocked, when I asked why I was told it was in my contract. When I read the contract I had signed to the operator I was put on hold. She came back and told me that it couldn't be unlocked, I told her it could as I had read online that it could. Then I hear in the background "just keep telling him it can't be unlocked". When I asked to speak to the person in the background telling her what to say she told me that there was no one telling her what to say. I told her I could hear the guy and that I wanted to either speak to the person or get their name so it could be included in a report to the TIO. I was again put on hold. About 1 minute later I was told that I would be transferred to data services.

After spending a little while on hold I got to speak to someone in data services. First they wanted to know why I wanted my card unlocked, I explained I could get a better deal elsewhere, to which the response was that I could talk to sales to see if there were any new offers available - I declined. Next I had to play 20 questions to make sure I was the account holder and that I was out of contract. After reading the IMEI code off the bottom of the card I was given the unlock code and told that I would be emailed the software - a zip file containing some Windows only application.

I had my content filtering too high so amavis bounced the message the first time. When I rung 3 back, at first 3 told me that I need to talk to my ISP as it was very strange that the message was bounced, I told them I would just use another account - my gmail account. The guy then told me that gmail bounces their messages, so we used my hotmail account.

So now I had the software, so I tried using XP under qemu to talk to the card for the unlocking, no luck. A few days later I borrowed a XP laptop from a friend. By now I had misplaced the unlock code. Back on the 3 merri go round, this time data services was happy to hand over the code. The operator waited on hold while I unlocked the card. I started the application, inserted the card, plugged in the unlock code and got the message confirming that the card was unlocked.

Later that day I tried using a vodafone SIM, no go. Another vodafone SIM no go. My Virgin SIM didn't work either. I tried using the unlock software which kept on erroring.

I thought going to a 3 store might get it fixed quickly. Basically I was told that as the card was out of warranty and I wasn't using a 3 SIM they wouldn't provide any support. The best I could do was pay for a firmware reload from a non authorised service centre.

Back to the 3 call centre merry-go-round. I explained that I was extremely close to lodging a TIO or Consumer Affairs complaint as the card useless and not working as advertised. I spoke to a helpful operator who told me he would escalate the job.

Over the weekend I spent a fair bit of time searching for answers. Eventually I ended up finding a list of AT+C modem commands. In the list was


which is for facility lock. I played with it a bit and found that network personalisation was still active, but no other locks were on. This seemed strange to me. I figured this is where my problem was.

This is how I unlocked my card. You must have a 3 (or locking carrier) SIM inserted in the card while attempting this.

I connected to the card using minicom by running the following in a terminal (I didn't need to be root).

minicom /dev/ttyS2
Minicom should then load and output something similar to this
Welcome to minicom 2.2

Compiled on Mar  7 2007, 15:10:03.
Port /dev/ttyS2

               Press CTRL-A Z for help on special keys
AT S7=45 S0=0 L1 V1 X4 &c1 E1 Q0                     

I then entered


which should return

+CLCK: ("AB","AC","AG","AI","AO","IR","OI","OX","PN","SC")


This is a list of locks available on the card.

Enter the following


Which means, for network personalisation (PN), query the status (2), which should output

+CLCK: 1


The 1 indicates locked.

You will need your unlock code from your carrier - I do not know how to get it other than via your carrier. This is not a "how to unlock your card with the unlock code" howto. So replace <CODE> with your unlock code.


The 0 is for unlock. If it works should get OK or something, I forget exactly the response, but ERROR means it failed.

Now your card is unlocked and should work with any carrier.

Use [ctrl] x to quit minicom.


If you need the settings details for using a Merlin U530 with Virgin Mobile in Australia under Linux try the following

connect "/usr/sbin/chat -v -f /etc/chatscripts/virgin"
460800 crtscts
# ispauth chat
# abortstring
# modeminit
'' ATZ
#OK 'AT IPR=115200'
# Check SIM pin should return ready
# Use either 3G or GPRS, remove comment to force 3G
# Setup AP name
OK-AT-OK 'AT+CGDCONT=1,"IP","VirginInternet"'
# Set PPP QoS info (I never saw the point of this)
#OK-AT-OK 'AT+CGEQREQ=3,3,64,384,0,0,2,0,"0E0","0E0",3,0,0'
# Attached to virgin network, will return 1
# create a ppp connection
OK-AT-OK 'ATD*99#'

post length

Russell Coker wrote:

What blog server are you using? Does it support the <!--more--> tag? If so putting the examples at the end of a long post such as this with the more tag splitting it would be a good idea to keep the feed size down.

Added Sun, 2007-06-10 11:14

Re: post length

Dave wrote:

I use drupal, which I thought uses <!--break-->. I will look into it. Sorry for the noise.

Added Mon, 2007-06-11 10:25

Thank you!

Anonymous wrote:

Thank you very much. I will try this. I got my unlock code SIX MONTHS ago and I am still waiting for my carrier to tell me how to use it ... This is now a pride issue ;). I'll get it. Which software do you use now with the pc-card?

Thanks again.

Added Sat, 2007-09-29 02:54


Dave wrote:

I just use pppd which ships with most GNU/Linux distros. You should also be able to run it under Windows with a few tweaks. It should just show up as a serial modem.

Added Tue, 2007-10-02 22:54

RE: Software

IT Services wrote:

It will run under windows and does show as a Serial modem.



Added Wed, 2008-11-05 06:53

I know you use this card for

Jon wrote:

I know you use this card for general browsing, however I have the same card and would like to use it for recieving text messages, have you tried this?

Added Mon, 2009-03-02 23:25

Thanks for the post, old yet

Raúl wrote:

Thanks for the post, old yet really current. I only have a pointer about it, the unlock command syntax should be changed from: AT+CLCK="PN",0,<CODE> to: AT+CLCK="PN",0,"<CODE>" If I'm corrrect you only have 5 chances to unlock the terminal, so you'd rather be careful with the important command.


Added Thu, 2010-03-18 18:58

Novatel x870

lolek wrote:

Well, this solution also works on Novatel Merlin xu870 ...

Added Sun, 2010-04-25 21:01

I wanted to thank you for

Dylan wrote:

I wanted to thank you for this great read. Your blog is one of the finest blog . Thanks for posting this informative article. piloter helicoptere

Added Fri, 2010-12-03 02:00

Out of place ...

IT Support wrote:

I see that someone has already tested this method on another model. I'll push it a bit further and ask. Would you think this can actually be applied to non Novatel hardware ... maybe to USB broadband dongles?

Added Sat, 2010-12-25 03:50

RE: Out of place ...

Dave wrote:

It should work. The commands are part of the GSM standard.

Disclaimer: If you brick your device, don't blame/sue me.

Added Tue, 2010-12-28 02:12

It works !!!

Linktheworlds wrote:

This solution works perfect !! Thx


Added Thu, 2011-03-03 04:53

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