1. Introdução
The Grandstream HT812 is a powerful 2-port Analog Telephone Adapter (ATA) designed for users seeking to convert traditional analog phones into Voice over IP (VoIP) devices. It features two FXS ports for connecting analog telephones and dual Gigabit Ethernet ports, including a built-in NAT router capable of handling routing speeds up to 100Mbps. This device supports 2 SIP profiles and incorporates advanced security encryption technologies like TLS and SRTP to protect calls and accounts, ensuring secure and reliable communication.
This manual provides detailed instructions for the proper installation, configuration, and operation of your HT812 device.
2. Conteúdo da embalagem
Por favor, verifique se sua encomenda contém os seguintes itens:
- Grandstream HT812 Analog Telephone Adapter
- Adaptador de energia universal
- Cabo Ethernet
- Quick Installation Guide (This document serves as the comprehensive user manual)
3. Excesso Físicoview
Familiarize yourself with the ports and indicators on the HT812 device.

Figura 1: Frente view of the Grandstream HT812, showing the power, phone line 1, phone line 2, internet, and LAN indicator lights.

Figura 2: Traseira view of the Grandstream HT812, displaying the power input, reset button, two LAN ports (blue), and two FXS phone ports (green).

Figura 3: Angulado view of the Grandstream HT812, showcasing its compact design and port layout from a side perspective.
4. Configuração e instalação
4.1 Connecting the HT812
- Conecte o cabo Ethernet:
- Connect the blue LAN port on the HT812 to your internet router or switch using an Ethernet cable.
- If using the HT812 as a router, connect your modem to the blue WAN port and your local network devices to the blue LAN port.
- Connect Analog Phones:
- Connect your analog telephone(s) to the green FXS ports (labeled 1 and 2) on the HT812 using standard RJ11 phone cables.
- Conecte a energia:
- Connect the power adapter to the DC 12V power input on the HT812 and then plug it into a power outlet.
- The power indicator light on the front panel should illuminate.
4.2 Acessando o Web Interface de Configuração
To configure the HT812, you need to access its web interface:
- Determine the IP Address:
- Connect an analog phone to FXS port 1.
- Discar *** (three asterisks) to access the IVR menu.
- When prompted, dial 02 to hear the device's current IP address.
- Alternatively, check your router's DHCP client list for a device named "Grandstream" or by its MAC address (found on the bottom of the HT812).
- Conecte-se:
- Abra um web browser on a computer connected to the same network as the HT812.
- Enter the IP address obtained in step 1 into the browser's address bar (e.g., http://192.168.1.100).
- O nome de usuário padrão é administrador e a senha padrão é administrador (or found on the physical device label).
4.3 Atualização de firmware
It is highly recommended to update the device firmware to the latest version for optimal performance and security.
- Faça login no web interface de configuração.
- Navegar para Maintenance > Upgrade and Provisioning.
- Set "Upgrade Via" to HTTP.
- Digitar firmware.grandstream.com in the "Firmware Server Path" field.
- Clique Aplicar na parte inferior da página.
- Reinicie o dispositivo a partir do web interface (Maintenance > Reboot) or by power cycling. The device will download and install the latest firmware. This process may take several minutes.
4.4 SIP Account Configuration
To make and receive calls, you need to configure your SIP account details provided by your VoIP service provider.
- Faça login no web interface de configuração.
- Navegar para Prófile 1 (or the relevant profile for your service).
- Configure the following settings based on your VoIP provider's information:
- Primary SIP Server: Enter your provider's SIP server address (e.g., sip.yourprovider.com).
- ID de usuário SIP: Your SIP username or phone number.
- ID de autenticação: Your SIP authentication ID (often the same as SIP User ID).
- Senha: Your SIP account password.
- Ensure "SIP Registration" is set to Sim.
- Clique Aplicar e então Reinício o dispositivo.
- After reboot, check the phone line indicator lights on the front panel. A solid blue light indicates successful SIP registration.
5. Instruções de operação
5.1 Fazendo e recebendo chamadas
Once your SIP account is registered, you can use your analog phone connected to the HT812 just like a regular phone line.
- Fazer uma chamada: Pick up the handset, wait for a dial tone, and dial the desired phone number.
- Recebendo uma chamada: When the phone rings, pick up the handset to answer.
5.2 NAT Router Functionality
The HT812 includes a built-in NAT router. When connected to your modem, it can provide network access to other devices connected to its LAN port. This functionality allows for efficient network management and can handle routing speeds up to 100Mbps.
5.3 Recursos de Segurança
The HT812 supports advanced security protocols to protect your communications:
- TLS (Transport Layer Security): Encrypts SIP signaling to prevent eavesdropping and tamperrante.
- SRTP (Secure Real-time Transport Protocol): Encrypts the voice data itself, ensuring privacy during calls.
These features can be configured within the web interface under the relevant SIP profile configurações.
6. Manutenção
6.1 atualizações de firmware
Regularly checking for and applying firmware updates is crucial for maintaining the security, stability, and performance of your HT812. Refer to section 4.3 for detailed instructions on how to update the firmware.
6.2 Cuidados com o dispositivo
- Keep the device in a cool, dry place, away from direct sunlight and excessive heat.
- Evite expor o dispositivo à água ou umidade.
- Limpe o dispositivo com um pano macio e seco. Não utilize produtos de limpeza líquidos ou em aerossol.
7. Solução De Problemas
This section addresses common issues you might encounter with your Grandstream HT812.
7.1 Sem tom de discagem
- Verifique a potência: Ensure the power adapter is securely connected and the power indicator light on the HT812 is on.
- Check Phone Connection: Verify that the analog phone is correctly plugged into one of the green FXS ports.
- Check SIP Registration: The phone line indicator light for the connected port should be solid blue. If it's off or blinking, the SIP account may not be registered. Review your SIP configuration in the web interface (Section 4.4).
- Conectividade de rede: Ensure the HT812 is connected to the internet and has a valid IP address. Check the internet indicator light.
7.2 Não é possível fazer ou receber chamadas
- Registro SIP: Confirm that your SIP account is successfully registered (solid blue phone line indicator).
- Conexão com a Internet: Verify that your internet connection is active and stable.
- Firewall/NAT Issues: If you are behind a firewall, ensure that the necessary VoIP ports (typically UDP 5060 for SIP and UDP 10000-20000 for RTP) are open or that NAT traversal settings are correctly configured in the HT812 web interface.
- Dial Plan: Check the dial plan configuration in the web interface to ensure it matches your dialing habits and service provider requirements.
7.3 Web Interface inacessível
- Endereço IP: Reconfirm the HT812's IP address using the IVR menu (dial ***02 from a connected phone) or your router's DHCP client list.
- Conexão de rede: Ensure your computer is on the same local network as the HT812.
- Credenciais padrão: If you forgot your password, you might need to perform a factory reset (see Section 7.4).
7.4 Redefinição de fábrica
A factory reset will restore all settings to their default values. This should be a last resort for troubleshooting.
- With the HT812 powered on, use a paperclip or a similar pointed object to press and hold the REINICIAR button (located on the rear panel, see Figure 2) for approximately 7 seconds.
- Release the button when the indicator lights start to flash rapidly.
- The device will reboot with factory default settings. You will need to reconfigure all settings, including SIP accounts and network parameters.
8. Especificações
| Modelo | HT-812 |
| Portas FXS | 2 |
| Portas Ethernet | Dual Gigabit (WAN/LAN) |
| NAT Router Speed | Até 100 Mbps |
| SIP Profiles | 2 |
| Segurança | TLS and SRTP encryption |
| Dimensões do produto | 9 x 13 x 2.8 polegadas |
| Peso do item | 10.2 onças |
| Entrada de energia | Corrente contínua 12 V |
9. Garantia e Suporte
9.1 Garantia do Produto
Grandstream products are covered by a limited warranty. For detailed warranty information, please refer to the warranty card included with your product or visit the official Grandstream website.
9.2 Suporte Técnico
If you encounter issues that cannot be resolved using the troubleshooting steps in this manual, please contact Grandstream technical support. You can find support resources, FAQs, and contact information on the official Grandstream website: www.grandstream.com/support.





