User manual
 FIRMWARE VERSION 1.0.14.1   HT503 USER MANUAL  Page 19 of 64  
PLACING A PHONE CALL 
PHONE OR EXTENSION NUMBERS 
There are currently two methods to make an extension number call: 
a) Dial the numbers directly and wait for 4 (default) seconds.  
b) Dial the numbers directly, and press # (assuming that “use # as dial key” is selected in the web 
configuration). 
Examples: 
  To dial another extension on the same proxy, such as 1008, simply pick up the attached phone, 
dial 1008 and then press the # or wait for 4 seconds.  
  To  dial a  PSTN  number such as 6266667890,  you  may need a  prefix number followed by the 
phone number. Please check with your VoIP service provider for this information. If your phone is 
assigned a PSTN-like number such as 6265556789, you will most likely follow the rule 1 + (the 
number) – 16266667890. Press # or wait for 4 seconds. 
DIRECT IP CALLS 
Direct IP calling allows two parties, that is, a FXS Port with an analog phone and another VoIP Device, to 
talk to each other in an ad hoc fashion without a SIP proxy.  
Elements necessary to completing a Direct IP Call: 
  Both HT503 and other VoIP Device, have public IP addresses, or  
  Both HT503 and other VoIP Device are on the same LAN using private IP addresses, or  
  Both HT503 and other VoIP Device can be connected through a router using public or private IP 
addresses (with necessary port forwarding or DMZ). 
HT503 supports two ways to make Direct IP Calling: 
Using IVR 
1.  Pick up the analog phone then access the voice menu prompt by dial “***” 
2.  Dial “47” to access the direct IP call menu 
3.  Enter the IP address using format ex. 192*168*0*160 after the dial tone. 










