Grandstream’s HT series of Analog Telephone Adapters (ATAs) offer a ton of features at an affordable price point. They are trusted and deployed by some of the world's largest service providers. The HT701 is a single-port FXS, with 10/100 Mbps ethernet and no router. It supports 1 SIP account.
Related Links:
EOL NOTICE: Although this unit is certified, we recommend Grandstream's newer HT801 for new installations.
Firmware
Update to the latest firmware for your HandyTone before connecting to our service. You can download the current production release from the link above. Once downloaded, you'll navigate to "Advanced Settings" and click the "Upload from Local Directory" button. Select the file you downloaded from Grandstream's website, and then click "Apply" once this has completed your device will reboot. You can then move on to the steps below.
SIP Registration
Select "FXS Port" from the primary menu, and and configure the following options for your SIP Registration:
- Primary SIP Server: sip.t38fax.com:5080 (?)
- NAT Traversal: Keep-Alive
- SIP User ID: SIP Username (?)
- Authenticate Password: SIP Password (will be blanked out when saved) (?)
Network Settings
Scroll down and configure the following options:
- Register Expiration: 5
- Local SIP Port: 5080 (?) - If you have more than one device at a site, each device at a site should have a unique port, such as 5081, 5082, etc..
- Allow Incoming Packets from SIP Proxy Only: Yes
 
Feature Settings
Scroll down and configure the following options:
- Disable-Call-Waiting: Yes
- Disable-Call-Waiting-Caller-ID: Yes
- Disable-Call-Waiting-Tone: Yes
Fax Settings
Finally, configure the following T.38 specific options further down the screen:
- Fax Tone Detection Method: Callee
- Jitter Buffer Type: Fixed
- Jitter Buffer Length: High
- Disable Line Echo Canceller (LEC): Yes
- Disable Network Echo Suppressor: Yes
Fax Machine
Finally, configure your fax machine to work properly with your Power-T.38 SIP Trunk. Review our Recommended Fax Machine Settings for details.