Uc520 PSTN Lines drop

Posted on 2011-04-21
Last Modified: 2013-12-29
I have installed a uc520 in australia with 4fx0 ports.  I currently have 2 pstn lines on the system which comprises of a mixture of ip and analogue phones.  The incoming calls ring fine but when you pick up the handset 1 of 3 things happen 1. line answers ok 2. line seems to drop but when you push line button on phone it answers 3. call drops altogether.  The phones are set up as a blast group.  Any help would be appreciated.

Question by:sfkelly
    LVL 13

    Accepted Solution

    I had a problem similar to this. Calls would drop after a couple of rings. Then when it would ring again, you would pick it up and it didn't work.

    Here is the solution - Keep in mind you will need to adjust the voice-ports to match your FXO ports on the uc520.

    Telnet into UC520

    config t
    FXO_Paper(config)#voice-port 2/1/1
    FXO_Paper(config-voice)#no battery-reversal

    Open in new window

    Do this for each FXO port. Worked like a charm for me.
    LVL 13

    Expert Comment

    Obviously you only have to worry about the code after the # sign.
    LVL 13

    Expert Comment

    Did this help?

    Author Comment


    Thanks for your fast reply but I am not getting back to project for a fews days will reply with an update.

    LVL 13

    Expert Comment

    Any updates on this?

    Assisted Solution

    Sorry have not been back to job it is in remote area phones are working for client so not urgent will update as soon as I attend

    Author Closing Comment

    Thanks heaps, I had found it hard to find solution to issue

    Write Comment

    Please enter a first name

    Please enter a last name

    We will never share this with anyone.

    Featured Post

    Enabling OSINT in Activity Based Intelligence

    Activity based intelligence (ABI) requires access to all available sources of data. Recorded Future allows analysts to observe structured data on the open, deep, and dark web.

    Suggested Solutions

    I recently purchased a Bluetooth headset called the Music Jogger (model BSH10). The control buttons on it look like this: One of my goals is to use it as the microphone and speakers for Skype calls. In that respect, it works well. However, I …
    Messaging apps are amazing tools with the power to do a lot of good, but the truth is the process of collaborating with coworkers requires relationships established through meaningful communication - the kind of communication that only happens face-…
    Sending a Secure fax is easy with eFax Corporate ( First, Just open a new email message.  In the To field, type your recipient's fax number You can even send a secure international fax — just include t…
    Internet Business Fax to Email Made Easy - With eFax Corporate (, you'll receive a dedicated online fax number, which is used the same way as a typical analog fax number. You'll receive secure faxes in your email, fr…

    794 members asked questions and received personalized solutions in the past 7 days.

    Join the community of 500,000 technology professionals and ask your questions.

    Join & Ask a Question

    Need Help in Real-Time?

    Connect with top rated Experts

    18 Experts available now in Live!

    Get 1:1 Help Now