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Grandstream HT802 adapter

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Connect an analogue phone or fax machine to your PBX with a Grandstream HT802 analogue telephone adapter (ATA).

The Grandstream HT802 is an analogue telephone adapter (ATA). It lets an ordinary analogue phone, cordless phone or fax machine make and receive calls through your PBX. It has two phone ports, and each port uses its own SIP device.

Before you start

Section titled “Before you start”
  1. Each port you’ll use needs its own SIP device, and each SIP device needs a device licence. Add a SIP device to a User (which needs a user licence) under Device configuration, and click Apply configuration.
  2. Open Devices at the top of the PBX tab and select the device. Keep its SIP credentials open: Domain, Username and Password.
  3. Connect the HT802 to your network and power, and plug an analogue phone into Phone 1 or Phone 2.

The Domain shows the server address, a colon and the port.

If Transport protocol shows TLS, TLS encryption is on for your PBX. The port in the Domain is then different, and you must set the adapter to use TLS instead of TCP, with SRTP (shown as Media encryption).

1. Find the adapter’s IP address

Section titled “1. Find the adapter’s IP address”
  1. On the analogue phone, press *** to open the HT802’s voice menu.
  2. When asked for a menu option, enter 02. The adapter reads out its IP address.
  3. Type that IP address into a web browser on your computer.

Sign in with the default username and password, admin and admin. If that doesn’t work, ask whoever supplied the adapter.

2. Enter the SIP details

Section titled “2. Enter the SIP details”

  1. Open the tab that matches the port your phone is plugged into: FXS PORT1 or FXS PORT2.

  2. Fill in:

    HT802 field What to enter
    Primary SIP Server The Domain, including the colon and port.
    SIP User ID The Username.
    Authenticate ID The Username.
    Authenticate Password The Password.
    SIP Transport TCP.
    Register Expiration 2 (this field is in minutes; the default is 60).
    Local SIP Port A number above 9000 that no other device on your network uses.

  3. Save and apply the settings.

HT802 FXS PORT1 tab with the Primary SIP Server field blurred

HT802 Register Expiration set to 2 minutes

Extra settings for a fax machine

Section titled “Extra settings for a fax machine”

Sending fax over the internet is unreliable, even with these settings, and your provider can’t guarantee it will work. To receive faxes, consider Fax to email instead.

If you connect a fax machine, also set on its port:

  • Disable Call-Waiting, Disable Call-Waiting Caller ID and Disable Call-Waiting Tone: Yes.
  • Jitter Buffer Type: Fixed, and Jitter Buffer Length: High.
  • Disable Line Echo Canceller (LEC) and Disable Network Echo Suppressor: Yes.

Check it works

Section titled “Check it works”
  1. In PBX › Devices, the SIP device shows Online.
  2. Pick up the analogue phone: you should hear a dial tone. Make a test call and ask someone to call you.

If it doesn’t register, see Softphone errors. A device that tries to register with a wrong password is blocked, and the block lifts after 5 minutes.

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