User Manual Analog Telephone Adaptor HandyTone-496
HandyTone-496 User Manual  Grandstream Networks, Inc. 
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divided into 24 time slots of 10ms, and twelve full-duplex accesses per carrier, for a total of 
120 possible combinations. A DECT base station (an RFP, Radio Fixed Part) can transmit all 
12 possible accesses (time slots) simultaneously by using different frequencies or using only 
one frequency. All signaling information is transmitted from the RFP within a multiframe (16 
frames). Voice signals are digitally encoded into a 32 kbit/s signal using Adaptive Differential 
Pulse Code Modulation.  
DNS 
Short for Domain Name System (or Service or Server), an 
Internet service that translates 
domain names into IP addresses 
DID 
 Direct Inward Dialing 
Direct Inward Dialing. The ability for an outside caller to dial to a PBX extension without 
going through an attendant or auto-attendant. 
DSP 
Digital Signal Processing. Using computers to process signals such as sound, video, and other 
analog signals which have been converted to digital form. 
Digital Signal Processor. A specialized CPU used for digital signal processing. 
  Grandstream products all have DSP chips built inside. 
DTMF 
Dual Tone Multi Frequency 
The standard tone-pairs used on telephone terminals for dialing using in-band signaling. The 
standards define 16 tone-pairs (0-9, #, * and A-F) although most terminals support only 12 of 
them (0-9, * and #). 
FQDN 
  Fully Qualified Domain Name 
A FQDN consists of a host and domain name, including top-level domain. For example, 
www.grandstream.com is a fully qualified domain name. www is the host, grandstream is the 
second-level domain, and.com is the top level domain. 
FXO 
 Foreign eXchange Office 
An FXO device can be an analog phone, answering machine, fax, or anything that handles a 
call from the telephone company like AT&T. They should also operate the same way when 
connected to an FXS interface. 
An FXO interface will accept calls from FXS or PSTN interfaces. All countries and regions 
have their own standards. 
FXO is complimentary to FXS (and the PSTN). 










