User Guide

Grandstream Networks, Inc.  HT-502 User Manual  Page 25 of 32 
  Firmware Version 1.0.4.2 Last Updated: 06/2011 
SIP T1 Timeout 
T1 is an estimate of the round-trip time between the client and server transactions. 
If the network latency is high, select larger value for more reliable usage. 
SIP T2 Interval 
Maximum retransmission interval for non-INVITE requests and INVITE responses. 
DTMF Payload Type 
Sets the payload type for DTMF using RFC2833. 
Preferred DTMF method 
The HT502 supports up to 3 different DTMF methods including in-audio, via RTP 
(RFC2833) and via Sip Info. The user can configure DTMF method in a priority list. 
Disable DTMF 
Negotiation 
Default is No. If set to yes, use above DTMF order without negotiation 
DTMF via RFC2833 
Send DTMF via RTP (According to RFC 2833). 
DTMF via SIP INFO 
Send DTMF via SIP INFO message. 
Send Flash Event 
Default is No. If set to yes, flash will be sent as DTMF event. 
Enable Call Features  Default is Yes. (If Yes, call features using star codes will be supported locally) 
Offhook Auto-Dial  This parameter allows users to configure a User ID or extension number that is 
automatically dialed when off-hook. Only the user part of a SIP address needs is 
entered here. The HT502 will automatically append the “@” and the host portion of the 
corresponding SIP address. 
Proxy-Require 
SIP Extension to notify SIP server that the unit is behind the NAT/Firewall. 
Use NAT IP 
NAT IP address used in SIP/SDP message. Default is blank. 
Distinctive Ring Tone 
Custom Ring Tone 1 to 3 with associate Caller ID: when selected, if Caller ID is 
configured, then the device will ONLY uses this ring tone when the incoming call is 
from the Caller ID. System Ring Tone is used for all other calls. When selected but no 
Caller ID is configured, the selected ring tone will be used for all incoming calls. 
Distinctive ring tones can be configured not only for matching a whole number, but also 
for matching prefixes. In this case symbol * (star) will be used. 
For example: 
 if configured as *617, Ring Tone 1 will be used in case of call arrived from the area 
code 617. Any other incoming call will ring using cadence defined in parameter System 
Ring Cadence located under Advanced Settings Configuration page. 
Note: If server supports Alert-Info header and standard ring tone set (Bellcore) or 
distinctive ring tone 1-10 is specified, then the ring tone in the Alert-Info header from 
server will be used. Bellcore rings and tones are independent from custom ring tones. 
The custom ring tones can also be specified by alert-info header, for example 
Alert-Info: <http://127.0.0.1>;info=ring5 
Disable Call Waiting 
Default is No. If set to YES Call Waiting indication information will not be provided to 
analog phone connected to this FXS port.  
Disable Call-Waiting 
Caller ID 
Default is No. If set to YES Call Waiting caller ID will not be provided to analog phone 
connected to this FXS port. 
Disable Call Waiting 
Tone 
Default is No. This is to disable the stutter Call Waiting Tone when a Call Waiting 
information arrives. The CWCID information will still be displayed. 
Disable Reminder Ring 
for On-Hold Call 
Default is No. Do not play the reminder ring when this is set to Yes. 
Disable Visual MWI  If set to “Yes”, the MWI information will not be transferred to the analog phone 
connected to the FXS port. 
Ring Timeout 
Incoming call will stop ringing when not picked up given a specific period of time. 
Delayed Call Forward 
Wait Time 
Default value is 20 seconds. In case this feature activated using * codes (*92 code), the 
call will be forwarded after this preconfigured amount of time. 
No Key Entry Timeout  Default is 4 seconds. Dialing process is completed and outgoing call is initiated if no 
key entry occurs during this preconfigured interval. 
Early Dial  Default is No. Use only if proxy supports 484 response. This parameter controls 
whether the phone will send an early INVITE each time a key is pressed when a user 
dials a number. If set to “Yes”, an INVITE is sent using the dial-number collected thus 
far; Otherwise, no INVITE is sent until the “(Re-)Dial” button is pressed or after about 5 










