1,GSM FWT ETS-4S is a newly designed 4 ports GSM to POTS (Plain Old Telephone Service) line Converter, also known as Fixed Wireless Terminal. The device has 4 line connections that allow 4 regular analog telephones to be connected to 4 Cellular GSM service just like connecting to 4 local PSTN (Public Switched Telephone Network) land-lines. Your calls are connected on the GSM network. This device receives and makes phone calls.
 
Model GSM FWT ETS-4S is 4 GSM modules + 4 FXS ports.
 
Model GSM FWT ETS-4S/O is 4 GSM modules + 4 FXS ports + 4 FXO ports .
 
You could choose:
 
1) Analog 4 FXS Port
2) Analog 4FXS+4 FXO Port
 
Factory default is 4 FXS PORT

(Also We have CDMA FWT ETS-4S (800Mhz Ruim Support) and WCDMA FWT ETS-4S option).

2, Functions & Features
Brand Name: Etross or OEM
Model Number: ETS-4S
Type: GSM (GSM FWT ETS-4S); GSM + PSTN (GSM FWT ETS-4S/O)
Port Number: ETS-4S: 4 ; ETS-4S/O: 8
SLIC (FXS): 4
DAA (FXO): 4
SIM Card slot: 4
IMEI changeable: support
LCR(Low cost routing): support
SMS management: support
lock network operator: support
Number transfer: support

1.  Use advanced Silicon Lab SLIC (FXS) and DAA (FXO) solution, the compatibility and the voice quality are in the high-level standard;
2. Can use command(by telephone set which connected to ETS-4S) or SMS(by mobile phone) to do function setting, flexible and convenient;
3. Can realize the LCR route between GSM and PSTN by presetting the dial rule;
4. Speed dialing (just like fixed line telephone dialing, no need to dial "#" when you finish your dialing) 
5.  Number transformation function
6.  PIN lock & Network Lock;
7.  The FXO interface has escape function


Features and Functions:
 
1) It is a 4 channels GSM Gateway that has 4 ports FXS interfaces. 
2) It can connect with ordinary telephone set, PBX , VOIP Gateway, Billing meter etc.
3) Dialing tone frequency:450hz
4) Employ Industrial module Quectel M35, UC-15(UMTS) to make             
 5) Can adjust dial interval from 0.5sec to 9 secs by setting up from telephone set                                         
 6) Can adjust voice volume by setting up from telephone set                              
7) SIM card supported (1.8V, 3V) 
8) Caller ID display 
9) DTMF Dialing
10) Bell signal
11) Polarity reversal
12) The RJ-11 socket which connect the phone or billing system for metering purpose
13) Antenna socket (SMA) 
14) IP Presetting.
15) Working status and Signal Strength by LED indicator                                                
16) IMEI Change (optional)
 
Technical Specifications
Air interface standard: GSM850/1900Mhz,900/1,800Mhz phase 2+ full band 
Frequency ranges:
A) GSM 850 GSM 1900:
I) Transmission: 869.2 ~ 893.8MHz I) Transmission: 1, 930 ~ 1, 990MHz
Ii) Reception: 824.2 ~ 848.2MHz Ii) Reception: 1, 850 ~ 1, 910MHz 
B) GSM 900: GSM 1800: 
I) Transmission: 890 ~ 915MHz I) Transmission: 1, 710 ~ 1, 785MHz 
Ii) Reception: 935 ~ 960MHz Ii) Reception: 1, 805 ~ 1, 880MHz 
Phone interface: supply RJ-11 Phone Interface
Hanging voltage: 45V
Picking off voltage: 30mA / 41mA
Dialing tone Frequency: 450Hz
Antenna interface: Antenna amplifying>2.5db
Sensitivity:<-104DBM
Transmitting power<3W
Color: White /Black (optional)
AC-Adapter interface: Input: AC 110~240VAC 50~60Hz
Output: 12DC 1A.
AC-Adapter type: EU, US, AU, British can be optional