Grandstream HT801 Setup

The Grandstream HT801 is a reliable, budget-friendly ATA that works great with fax machines. Follow these steps to connect it to faxsimile.

What You'll Need

Step 1: Connect the Hardware

  1. Plug the ethernet cable from your router into the WAN port on the HT801
  2. Connect your fax machine's phone cable to the Phone port on the HT801
  3. Plug in the power adapter
  4. Wait for the Power LED to turn solid green (about 30 seconds)

Step 2: Find the Device's IP Address

You need to access the HT801's web interface. First, find its IP address.

  1. Pick up your fax machine's handset (or any phone connected to the HT801)
  2. Press *** (three stars)
  3. Wait for the voice prompt, then press 02
  4. The device will read out its IP address (e.g., "192.168.1.105")
  5. Write this down - you'll need it for the next step

Step 3: Access the Web Interface

  1. On your computer, open a web browser
  2. Type the IP address from Step 2 into the address bar (e.g., http://192.168.1.105)
  3. You'll see a login page
  4. Leave username blank, enter password: admin
  5. Click Login

Note: If "admin" doesn't work, try "123" - the default password varies by firmware version.

Step 4: Configure SIP Settings

  1. Click FXS PORT in the top menu
  2. Find and fill in these settings:
Primary SIP Server sip.faxsimile.net
SIP User ID your extension
Authenticate ID your extension
Authenticate Password your password
SIP Registration Yes

Step 5: Optimize for Fax

These settings help fax transmissions work reliably over internet connections.

  1. Still on the FXS PORT page, find these settings:
Preferred Vocoder PCMU (or G.711u)
Fax Mode T.38 (or "T.38 with fallback to G.711")
Jitter Buffer Type Fixed
Silence Suppression No
Echo Cancellation No

Step 6: Save and Reboot

  1. Scroll to the bottom and click Apply
  2. Click Reboot (or go to Status → Reboot)
  3. Wait about 60 seconds for the device to restart
  4. The Phone LED should turn solid green when registered

You're Connected!

If the Phone LED is solid green, your fax machine is ready to receive faxes. Make sure your fax machine is turned on and set to auto-answer.

Back to Dashboard

Troubleshooting

Phone LED is blinking or off
Registration failed. Double-check your SIP credentials are entered exactly as shown on your dashboard.
Faxes fail partway through
Try changing Fax Mode from "T.38" to "Pass-through" or vice versa. Some fax machines work better with one or the other.
Can't access web interface
Make sure your computer is on the same network as the HT801. Try unplugging and replugging the ethernet cable.
Forgot the password
Factory reset: Hold the reset button for 10 seconds while powered on. Default password will be restored.