User manual

3.3.4. Subscriber Disconnection (Power Down)

If a subscriber blocks the GSM Gateway unnecessarily by not hanging up after the call, he or

she will get the busy tone

first and then is disconnected (Power Down status).

3.4. Begin and end of connection signalling

Signalling by a current break or polarity change (see parameters 231 to 234) works

differently in a case of GSM and PSTN call:

GSM call: signals may be generated by GSM gateway, according to parameters 231 to 234.

PSTN call: signals may be only passed from PSTN network.

NOTES:

• This difference may cause some problems, be careful when using this function.

• GSM gateway is physically switching PSTN line to PBX line during PSTN calls. To

avoid possible polarity change in the moment of switching, GSM gateway checks

PSTN line polarity after power on and optionally reverse polarity of PBX line to match

polarity of PSTN line. When connecting to other PSTN line, always switch GSM

Gateway off. Otherwise, polarity change may cause some problems, and also audible

clicks are louder.

3.5. Power failure

During power failure (or if power cord is disconnected), PBX and PSTN connectors are

interconnected. It means that all calls are realized via PSTN, and GSM gateway cannot bare

any calls, of course.

3.6. Automatic dialling ("baby call")

Outgoing calls are described in chapters 3.1 and 3.2 on the assumption that automatic

dialling is off (default). If parameter "

Number for automatic dialling" is filled, this function is

automatically switched on and GSM gateway operates as follows:

As soon as line is picked up, GSM gateway awaits dialling for limited time, defined by

parameter "

time for automatic dialling". If user starts dialling within this time, GSM gateway

operates normally, as described in chapter 3.1. Otherwise, if this time is out, GSM gateway

automatically makes a call to programmed number. “Baby call” is always routed via GSM

network.

Note: It is assumed, that GSM gateway is connected to

phone. If GSM gateway is

connected to PBX, applicability of automatic dialling function depends on PBX's settings.

3.7. Intelligent Incoming Call Routing

This function can be applied to incoming calls from GSM only (if enabled). If CLIP (number

of calling subscriber) is found in Intelligent Incoming Call Routing Table (see chapter 7.4.), GSM

gateway will call a dedicated extension according to this table. If GSM gateway is connected to

external (C.O.) line of PBX, DISA function must be used in PBX to serve it. This function is

operating automatically, as described in previous chapter 3.3.