Grandstream ht-503 用户手册

 

Grandstream Networks, Inc. 

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Default is Callee.  This decides whether Caller or Callee sends out the re-invite for T.38 
or Fax Pass-Through. 

Select either Fixed or Adaptive based on network conditions. 

Select Low, Medium, or High based on network conditions. 

Secure RTP protocol used for media transmission over VoIP.  Disabled by default.  
Other modes are: enabled but not forced & enabled and forced. 

Bellcore/Telcordia, ETSI-FSK, ETSI-DTMF, SIN 227 – BT, & NTT Japan 

An adjustable value for the Caller ID signal to help this device to recognize Caller ID 
from different networks. (-50 -0dB.  Default -30dB) 

According to customer’s choice CID information will be transferred from PSTN network 
to VoIP network using following rules: 

1.  via SIP from - PSTN CID is in the SIP From field 

2.  via P-Asserted-Identity - SIP From field uses the pre-configured account user 

Id. PSTN CID is in the P-Asserted-Identity field 

3.  Send anonymous - SIP From field uses "anonymous". PSTN CID is put in the 

P-Asserted-Identity field 

4.  Disable - PSTN CID will not be sent. SIP From field uses the pre-configured 

account user ID 

The time period when the cradle is pressed (Hook Flash) to simulate a FLASH.  Adjust 
this time value to prevent unwanted activation of the Flash/Hold and automatic phone 
ring-back. 

Voice path volume adjustment.   

• 

RX is a gain level for signals transmitted by FXO (FXO-To-VoIP volume )  ,  

• 

TX is a gain level for signals received by FXO( FXO-To-PSTN volume).   

Default =  0dB for both parameters. Loudest volume: +6dB;  Lowest volume:  -6dB.  

User can adjust volume of call on either end using the Rx Gain Level parameter and 
the Tx Gain Level parameter located on the FXO Port Configuration page. These 
parameters affects call volume ONLY for calls placed to/from PSTN and VoIP 
networks. 

If call volume is too low when using VoIP extension, adjust volume using the Rx Gain 
Level parameter under the FXO Port Configuration page. 

If voice volume is too low at the other end (PSTN side), user may increase the far end 
volume using the Tx Gain Level parameter under the FXO Port Configuration page. 

Default is Yes.  This value should be used in case the PSTN provider uses line power 
drop to indicate call completion to the end point.  In this case the HT503 will search for 
a power drop for a preconfigured time frame to disconnect such calls from a VoIP 
extension. 

This is a preconfigured value of duration for a line power drop used by specific service 
providers.  For example, for a configured value of 500ms the device will ignore any 
random voltage drops on the line if duration of such drop is less than 500ms and the 
call will NOT be considered as terminated.  This is useful to prevent unnecessary call 
drops in some low quality PSTN lines. 

If set to Yes, arrived Busy Tone is used as the disconnect signal. 

In certain countries, the central office will send a special busy tone to indicate when a 
call is disconnected from the remote side.  User can pre-configure this tone on the 
ATA. The user should know the frequency values and cadences of these tones. 
Here is an example for the syntax for a busy tone in the U.S.A: 

AC Termination is a configurable value of impedance of the line provided by different