Grandstream HT503 Gateway



  • Does anyone have any experience with the Grandstream HT503 "FXO Gateway" devices and interfacing them to an analog paging system? We have a client who has a cloud hosted FreePBX system. Until they get a new paging system, we need to interface with their existing analog paging system. The existing paging system provides dial tone to any device plugged into it. (If I plug in an analog phone, I hear dial tone. Then I can dial some codes to route audio to different zones.) However, when plugging in the HT503 using the FXO/line port, and dialing the extension assigned to that port(80), I receive busy signal. Via the Asterisk console, I can prove that the call is being routed to the HT503. However, no dial tone is heard, and I hear a busy signal. Asterisk says:

    Connected line update to SIP/249-00001d15 prevented.
    -- Got SIP response 486 "Busy Here" back from xxx.xxx.xxx.xxx:xxxxx
    -- SIP/80-00001d17 is busy
    == Everyone is busy/congested at this time (1:1/0/0)

    I've been using this guide using step 1.

    Anyone have any experience with this sort of thing?



  • @fuznutz04 said in Grandstream HT503 Gateway:

    Does anyone have any experience with the Grandstream HT503 "FXO Gateway" devices and interfacing them to an analog paging system? We have a client who has a cloud hosted FreePBX system. Until they get a new paging system, we need to interface with their existing analog paging system. The existing paging system provides dial tone to any device plugged into it. (If I plug in an analog phone, I hear dial tone. Then I can dial some codes to route audio to different zones.) However, when plugging in the HT503 using the FXO/line port, and dialing the extension assigned to that port(80), I receive busy signal. Via the Asterisk console, I can prove that the call is being routed to the HT503. However, no dial tone is heard, and I hear a busy signal. Asterisk says:

    Connected line update to SIP/249-00001d15 prevented.
    -- Got SIP response 486 "Busy Here" back from xxx.xxx.xxx.xxx:xxxxx
    -- SIP/80-00001d17 is busy
    == Everyone is busy/congested at this time (1:1/0/0)

    I've been using this guide using step 1.

    Anyone have any experience with this sort of thing?

    You do not use an FXO to interface to a paging system.

    You use and FXS.

    Or more preferably, you use a paging adapter such as the Snom PA-1.



  • @fuznutz04 So are you correctly using the FXS port on the unit or the FXO port?



  • @JaredBusch said in Grandstream HT503 Gateway:

    @fuznutz04 So are you correctly using the FXS port on the unit or the FXO port?

    Normally, with other ATA devices, we use the FXS port, as most devices we plug in are expecting to hear a dial tone. (Fax machines, analog phones, etc) However, we are connecting this device (HT503) to a paging system that delivers dial tone. On their old phone system, they would dial a number that would open a connection from their phone system to the Paging system. After a pause, they would hear dial tone which was being delivered from the Paging adapter. I was assuming that I'd need to use the FXO port to get that type of functionality. But again, I could be way off, as this is the first time dealing with this sort of system.



  • @fuznutz04 said in Grandstream HT503 Gateway:

    @JaredBusch said in Grandstream HT503 Gateway:

    @fuznutz04 So are you correctly using the FXS port on the unit or the FXO port?

    Normally, with other ATA devices, we use the FXS port, as most devices we plug in are expecting to hear a dial tone. (Fax machines, analog phones, etc) However, we are connecting this device (HT503) to a paging system that delivers dial tone. On their old phone system, they would dial a number that would open a connection from their phone system to the Paging system. After a pause, they would hear dial tone which was being delivered from the Paging adapter. I was assuming that I'd need to use the FXO port to get that type of functionality. But again, I could be way off, as this is the first time dealing with this sort of system.

    Nope, you are correct based on this description. This is atypical though.

    I really suggest you look into the Snom PA-1 as a much better interface to paging systems.

    But to the point, what is the model of the paging system? Most paging systems accept multiple types of input. Just because that is what it used to do does not mean you have to hook it up that way.



  • 0_1472678591620_image.jpg



  • @JaredBusch

    I'm using one of those at another location with a similar paging system. But it's a more Basic system that just accepts an audio feed. The thing that is throwing me off with this paging system is the fact that it delivers dial tone . It's a Raulands Telecenter V. If I can't get this working via an ATA, I'll have to see if it will accept just an audio feed from a Snom. In your setup, where are you connecting the snom to the pagin system? via the red/black audio jacks on the back of the snom?



  • Never mind on that last question... I see it in the pic now.



  • @fuznutz04 said in Grandstream HT503 Gateway:

    Never mind on that last question... I see it in the pic now.

    The Snom also has an RJ11 port that can be connected to. I have done that at some clients.



  • @JaredBusch

    So thinking this through with using the PA-1...

    If I use the PA-1, configure it with an extension, and set it to auto answer, then use the RJ11 port to plug into the paging system RJ11 jack (master handset port that delivers dialtone) then the caller should hear dial tone and control their paging like they could previously. Does the PA-1 RJ11 jack function like this, or is it meant to be directly spliced into audio inputs on an amplifier?



  • @fuznutz04 said in Grandstream HT503 Gateway:

    @JaredBusch

    So thinking this through with using the PA-1...

    If I use the PA-1, configure it with an extension, and set it to auto answer, then use the RJ11 port to plug into the paging system RJ11 jack (master handset port that delivers dialtone) then the caller should hear dial tone and control their paging like they could previously. Does the PA-1 RJ11 jack function like this, or is it meant to be directly spliced into audio inputs on an amplifier?

    I would have to test. I have only used a handset plugged into that for testing at some clients.


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