The call '''signalling''' settings of the analogue FXS interfaces can be adjusted here:

{|
|valign=top nowrap=true|'''Disable:'''
| Disables the relevant analogue FXS interface.
|-
|valign=top nowrap=true|'''Speech Bearer Capability:'''
|Calls on the relevant interface are transmitted with Audio Bearer Capability as standard. A checked check box transmits calls from the relevant interface with Speech Bearer Capability. This only makes sense if only telephones are operated on the relevant interface (no fax machine or modem).
|-
|valign=top nowrap=true|'''Busy on Busy / No Call Waiting:'''
|A checked check box disables the call waiting signal for waiting calls on the relevant interface. Instead, Call busy is signalled to the calling side. This is necessary if, for example, a fax machine is operated on the relevant interface. ''Note that call waiting is generally only possible if 'feature codes' are enabled for this interface. It might be neccessary to switch on the 'call waiting' functionality explicitly with *43#. This checkmark refuses 'call waiting' even if activated within 'feature codes' and is a safe setting especially for fax machines.''
|-
|valign=top nowrap=true|'''Passive:'''
|Transfers the relevant interface to the passive mode. As a result, the Flash/Hook signal (R key) is not evaluated.
|-
|valign=top nowrap=true|'''No Call Transfer on Hook-On:'''
|A checked check box disables the call transfer function. Per default calls will be transfered on hook-on. Afterwards a call has been established, this call can be held and a new call can be initiated by pressing the R-Key. If the new call has been established or is yet ringing, the held and new call can be transferred together by hooking on the handset. There is a special exception : When the second call comes by ''call waiting'', what means, that you have your first call currently on hold, hooking on will NOT transfer the call waiting call with the previous, because this looks like an accident. If you really want to connect them you have to do this by 'R-4'. Hooking on will disconnect the call waiting call and the currently hold call will ring again (for 5 sec). If you use 'R-2' to switch between the call waiting call and the held call, this limitation is cleared and you may now transfer both calls together again by just hooking on.
|-
|valign=top nowrap=true|'''Signaling tones audibility:'''
|In normal operation in-band signaling tones are provided like well known from any phone provider. When the a/b is used in conjunction with a DOOR-Interface Converter, it may be desirable that the disconnect signaling tones at the end of a call are not audible to the person at the door. Checking 'in call establishing phase only' does so, but does not suppress the signalling tones in call establishing phase. This implies that the person at the door will hear typical telephone sounds after pressing the doorbell-button. This mode additionally disables recognition of flash (R) pulses. Checking 'never/silent' additionally supresses singalling tones in call establishing phase, so that there will be no audible telephone sounds at all to the person at the door. This mode disables recognition of flash (R) AND DTMFs as well. This might be the typical choice for DOOR-Interfaces.
|-
|valign=top nowrap=true|'''Reverse polarity in conversation/connected state:'''
|If checked, the gateway will reverse the line polarity to 'conversation/connected state polarity' as soon as the connection to the peer side is established. As a result of this, the line polarity returns to normal polarity again if the peer hooks up the connection. In addition a busy tone is provided. Equipment connected to the FXS port may take advantage of this additional information and safely detect call state details.
|-
|valign=top nowrap=true|'''Volume:'''
|Sets the output volume to the relevant interface (from IP to FXS), in decibel (dB), between -32dB and +32dB. No value or the value 0 is equal to the factory settings.
|-
|valign=top nowrap=true|'''Metering pulse every:'''
|The gateway can generate periodic metering pulses in fixed intervals of time. The value specified here is the time between two successive pulses. A value of 0 or no value disables pulse generation. ''Note that metering pulses are only generated for outgoing calls. The first metering pulse is generated when the call is connected. Note also that enabling pulse metering implicitly switches on '''Passive''' and '''No Call Waiting''', so that no call can be held and no incoming caller is accepted within a call.''
|-
|valign=top nowrap=true|'''Caller ID 1 standard:'''
|CallerId/CLIP can be sent in different ways depending on the country. The basic difference is the type of modulation used. Possibilities are DTMF (Dual Tone Multiple Frequency) and FSK (Frequency Shift Keying). FSK modulation splits up into the Telcordia/Bellcore and ETSI scheme. DTMF modulation has several subsidaries and differ in special digits preceding and succeeding the number information.
 Examples using 1234567890 as calling number :
 ETSI DTMF : A1234567890C or D1234567890C
 Danish DTMF : A1234567890* or D1234567890*
 Indian DTMF : 1234567890
 Brazilian DTMF : A11234567890C or AB1234567890C
 The gateway will add these additional digits to the calling number as shown above, depending on the standard selected.
|-
|valign=top nowrap=true|'''Caller ID 1 include Date/Time:'''
|If checked, the gateway adds Date/Time information in FSK CallerID/CLIP.
|-
|valign=top nowrap=true|'''Country specific exceptions:'''
|This topic list countries that define some exceptions in handling specific events.
 In Brazil Flash events with a duration of less than 140ms have to be handled as illegal and are therefore ignored.
|}

Reference15r1:Interfaces/FXS/Signaling

2025-10-01T14:09:24Z

Cmu: Created page with "The call '''signalling''' settings of the analogue FXS interfaces can be adjusted here: {| |valign=top nowrap=true|'''Disable:''' | Disables the relevant analogue FXS interface. |- |valign=top nowrap=true|'''Speech Bearer Capability:''' |Calls on the relevant interface are transmitted with Audio Bearer Capability as standard. A checked check box transmits calls from the relevant interface with Speech Bearer Capability. This only makes sense if only telephones are ope..."

Reference16r1:Interfaces/FXS/Signaling

2025-10-01T14:08:26Z

Cmu: Blanked the page

Reference16r1:Interfaces/FXS/Signaling

2025-10-01T13:47:25Z

Cmu:

2019-04-01T12:33:04Z

Cmu: Reverted edits by Cmu (Talk); changed back to last version by Vsc

Reference11r1:Interfaces/FXS/Physical

2019-04-01T12:29:40Z

Cmu:

The '''physical''' settings of the analogue interfaces can be made here:

{|
|valign=top nowrap=true|'''Pulse:'''
| A checked check box enables the recognition of pulse dialling on the relevant interface.
|-
|valign=top nowrap=true|'''Reverse:'''
| A checked check box inverts the wiring of the relevant interface. This is only necessary in the event of incompatibility of the terminals, since some terminals (for example, in the US) are wired the opposite way.
|-
|valign=top nowrap=true|'''Ring cadence and CLIP transmission sequence:'''
| Set the interworking of CLIP and Ring cadence to different combinations. Possible options are :
'''Normal cadence, CLIP transmission 200ms after first AC ring ended'''
 Typically internal and external calls use different cadence to give the user an audible hint of the orgin of a call. Normally the internal ringing cadence starts with two short ring pulses. But there is not enough time to place CLIP information between these two ring pulses, so CLIP transmission will be postponed after the second ring pulse. If this doesn't matter you can use this option.
 '''Short AC ring pulse of 160ms, 200ms pause, CLIP transmission, pause min. 800ms, normal cadence'''
 Some telephones can explicitly suppress the first ring just to receive and present CLIP before audible ringing (often called ''1.st Ring OFF'' in menues). In this case the 'short AC ring' option is recommended, but not essential for correct working. But : There are also telephones that do not accept CLIP information after the second AC ring pulse, like happening within the 'Normal cadence' option. Here the 'short AC ring' option is mandatory to get CLIP working. Here it is guaranteed that CLIP is sent after exacly ONE AC ring. One known model of that kind is the '''T-COM Concept P412'''.
 '''Line polarity reversed, 200ms pause, CLIP transmission (duration depending on data amount), line polarity normal, 1000ms pause, normal cadence'''
 In some countries it is common that CLIP is preceded by a line polarity reversal instead of a AC ring pulse prior to CLIP transmission. In this case the 'Line polarity reversed' option must be chosen. This procedure is very common with CLIP using DTMF transmission and can be found in Sweden and other countries.
|-
|valign=top nowrap=true|'''Ring cadence generation timing:'''
|Normally internal and external calls are distinguished by terms of different rythms of the ringing voltage. Normally external calls use ''1sec ringing voltage - 4sec pause''. Internal calls normally use ''375ms ringing voltage - 250ms pause - 375ms ringing voltage - 4sec pause''. Select ''swiss'' to assign this rythms the opposite way. You can also select one rythm to be used permanently, no matter if the calls are external or internal.
|-
|valign=top nowrap=true|'''Number of CLIPs:'''
| You can change the number of CLIPs to be sent in AC ring pauses from 0 up to 5. 0 will completely suppress CLIP.
|-
|valign=top nowrap=true|'''Receive gain:'''
| Set the loudness a user receives at this interface. Default is -10dB for short lines and -7 dB for long lines.
|-
|valign=top nowrap=true|'''Transmit gain:'''
| Set the loudness a user transmits at this interface. Default is -3dB for short lines and 0 dB for long lines. Some fax devices may need a lower transmit level to avoid clipping.
|-
|valign=top nowrap=true|'''Country:'''
| Set the line impedance for different countries. In Europe CTR21 is used.
|-
|valign=top nowrap=true|'''Metering pulse frequency:'''
|possible values : 16kHz or 12kHz. 16kHz is common for most countries. Austria and Swiss use 12kHz.
|}

====Receive and transmit sides====

{| border=4
|+
|FXS Gateway representing central office/PABX
|::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::direction:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
|phone
|-
|PCM DAC
|>>>>>>>>>>>>>>>>>>>>>>>>>>>>>----receive direction---->>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
|phone speakerphone
|-
|PCM ADC
|<<<<<<<<<<<<<<<<<<<<<<<<<<<<<----transmit direction----<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
|phone microphone
|}

==== Some considerations about Flash, R and Dial-pulses ====

The a/b ports support further signaling through '''Flash'''-key (other sources call it '''R'''-key, what means exactly the same) followed by DTMF-Key combinations. For example, pressing '''Flash''' while already having a peer connection will set the current connection into call-hold state (the peer side hears ''Music-On-Hold'') and establish a new call. 

From a technical point of view '''Flash''' is a short interruption in offhook loop-current. You can imagine '''Flash''' as a very short hook-on/hook-off event. The on-hook duration of a '''Flash''' event is normally between 100ms and 300ms. Shorter durations are regarded as dial-pulses (if enabled), longer durations are regarded as seperate hook-on and hook-off events. If you encounter difficulties regarding '''Flash''', be sure you have configured a flash-time between 100ms and 300ms in your phone. 
 
'''Dial-pulse'''s are also short interruptions of the offhook loop-current and can also be imagined as short hook-on/hook-off events. The only difference to ''Flash'' is, '''Dial-pulse'''s have a much shorter duration of 40ms to 80ms. 
Several successive '''Dial-pulse'''s form a digit of a number. The pulses of one digit are seperated by a pause of about 60-80ms. Different digits are seperated with pauses that are much longer (at least 80ms, but can be much more). The digit '1' consists of one single pulse, '2' is two successive pulses and so on, '0' is ten successive pulses.

==== Pinout of the a/b connector ====
[[Image:RJ11.gif]]

{| border=1
|+
|Pin
|Function
|-
|3
|TIP
|-
|4
|RING
|-
|}

==== Pinout of the a/b connector IP29-20====
[[Image:RJ45-dn.gif]]

{| border=1
|+
|Pin
|Function
|-
|1
|RING-1
|-
|2
|TIP-1
|-
|3
|RING-2
|-
|4
|TIP-3
|-
|5
|RING-3
|-
|6
|TIP-2
|-
|7
|RING-4
|-
|8
|TIP-4
|-
|}
This pinout is especially designed for use with twisted-pair Ethernet patch cables

Reference9:Interfaces/FXS/Physical

2019-04-01T12:24:21Z

Cmu:

The '''physical''' settings of the analogue FXS interfaces can be made here:

{|
|valign=top nowrap=true|'''Pulse:'''
| A checked check box enables the recognition of pulse dialling on the relevant interface.
|-
|valign=top nowrap=true|'''Reverse:'''
| A checked check box inverts the wiring of the relevant interface. This is only necessary in the event of incompatibility of the terminals, since some terminals (for example, in the US) are wired the opposite way.
|-
|valign=top nowrap=true|'''First ring followed by CLIP:'''
| This checkbox creates a short ring pulse of 160ms duration followed by a pause of 1 second. This pause is then used to send CLIP information to the phone. Then the ringing switches over to the normal intervals depending on the call being internal or external. If not checked the ringing directly starts with the corrosponding interval. Some telephones can explicitly suppress the first ring just to receive and present CLIP before audible ringing (often called ''1.st Ring OFF'' in menues). If a telephone cannot suppress the first ring or is not configured to do so, this checkbox may be unchecked to immediately start ringing without a short audible ring, which will occur otherwise. '''Telephones that do not accept CLIP information after the second ring need this checkbox checked to present CLIP correctly. One known model is the T-COM Concept P412.'''
|-
|valign=top nowrap=true|'''Receive gain:'''
| Set the loudness a user receives at this interface. Default is -10dB for short lines and -7 dB for long lines.
|-
|valign=top nowrap=true|'''Transmit gain:'''
| Set the loudness a user transmits at this interface. Default is -3dB for short lines and 0 dB for long lines. Some fax devices may need a lower transmit level to avoid clipping.
|-
|valign=top nowrap=true|'''Country:'''
| Set the line impedance for different countries. In Europe CTR21 is used.
|-
|valign=top nowrap=true|'''Internal/External call distinction:'''
|Normally internal and external calls are distinguished by terms of different rythms of the ringing voltage. Normally external calls use ''1sec ringing voltage - 4sec pause''. Internal calls normally use ''375ms ringing voltage - 250ms pause - 375ms ringing voltage - 4sec pause''. Select ''swiss'' to assign this rythms the opposite way. You can also select one rythm to be used permanently, no matter if the calls are external or internal.
|-
|valign=top nowrap=true|'''Metering pulse frequency:'''
|possible values : 16kHz or 12kHz. 16kHz is common for most countries. Austria and Swiss use 12kHz.
|-
|valign=top nowrap=true|'''Optimization grade:'''
|As per default the TEL ports are optimized for low power consumption (Optimization 'high' and 'mid'). This decreases the usual on-hook supply voltage of 48V down to 24V. Most conventional phones and faxes can deal with this. In case a special phone is connected that cannot deal with this low voltage or if a long cable is used this dropdown can be modified. 'high' and 'mid' both set 24V on-hook voltage. The off-hook loop current is set to 20mA. 'low' sets 48V on-hook-voltage. The off-hook loop current is now configurable in three steps : The output voltage of an IP28 port can’t be changed. It’s fix to 35 V.
|-
|valign=top nowrap=true|'''Loop Current:'''
|As described before this topic changes the off-hook loop current and can be modified if 'Optimization grade' is set to 'low'. 'low' sets 20mA, 'mid' set 23mA, 'high' sets 26mA. Specific gateways may offer additional higher values.
|-
|valign=top nowrap=true|'''RingTrip Threshold:'''
|This topic modifies the current-threshold which lets the gateway distinguish between a ringing condition and a hook-off condition while the ringing voltage is applied from the gateway to the phone. Crossing this threshold by the phone, the gateway assumes a hook-off and therefore stops applying the ringing voltage and enters normal off-hook state. Imagine you encounter a problem that looks like this : very short time ringing, somehow immediate off-hook and then on-hook transition again - this call is lost. This looks like your phone requires too much current for ringing that makes the gateway wrongly assume a hook-off. In this case it is recommended to try the higher threshold currents. 'low' sets 34mA, 'mid' sets 37,5mA and 'high' sets 40mA.
|-
|valign=top nowrap=true|'''Ringing Voltage'''
|This topic modifies the ringing voltage used for ringing. Ringing frequency is 25Hz. 'low' sets 65Vpk/45Vrms, 'mid' sets 68Vpk/48Vrms and 'high' sets 70Vpk/49,5Vrms AC.
|}

==== Some considerations about Flash, R and Dial-pulses ====

The a/b ports support further signaling through '''Flash'''-key (other sources call it '''R'''-key, what means exactly the same) followed by DTMF-Key combinations. For example, pressing '''Flash''' while already having a peer connection will set the current connection into call-hold state (the peer side hears ''Music-On-Hold'') and establish a new call. 

From a technical point of view '''Flash''' is a short interruption in offhook loop-current. You can imagine '''Flash''' as a very short hook-on/hook-off event. The on-hook duration of a '''Flash''' event is normally between 100ms and 300ms. Shorter durations are regarded as dial-pulses (if enabled), longer durations are regarded as seperate hook-on and hook-off events. If you encounter difficulties regarding '''Flash''', be sure you have configured a flash-time between 100ms and 300ms in your phone. 
 
'''Dial-pulse'''s are also short interruptions of the offhook loop-current and can also be imagined as short hook-on/hook-off events. The only difference to ''Flash'' is, '''Dial-pulse'''s have a much shorter duration of 40ms to 80ms. 
Several successive '''Dial-pulse'''s form a digit of a number. The pulses of one digit are seperated by a pause of about 60-80ms. Different digits are seperated with pauses that are much longer (at least 80ms, but can be much more). The digit '1' consists of one single pulse, '2' is two successive pulses and so on, '0' is ten successive pulses.

==== Pinout of the a/b connector IP29-2, IP29-4, IP29, IP38====
[[Image:RJ11.gif]]

{| border=1
|+
|Pin
|Function
|-
|3
|TIP
|-
|4
|RING
|-
|}

==== Pinout of the a/b connector IP29-20====
[[Image:RJ45-dn.gif]]

{| border=1
|+
|Pin
|Function
|-
|1
|RING-1
|-
|2
|TIP-1
|-
|3
|RING-2
|-
|4
|TIP-3
|-
|5
|RING-3
|-
|6
|TIP-2
|-
|7
|RING-4
|-
|8
|TIP-4
|-
|}
This pinout is especially designed for use with twisted-pair Ethernet patch cables

2015-11-16T16:49:59Z

Cmu:

The '''advanced''' settings of the analogue interfaces can be made here:

{|
|valign=top nowrap=true|'''Optimization grade:'''
|Present on ip22/24/28 gateways only 
As per default the TEL ports are optimized for low power consumption (Optimization 'high' and 'mid'). This decreases the usual on-hook supply voltage of 48V down to 24V. Most conventional phones and faxes can deal with this. In case a special phone is connected that cannot deal with this low voltage or if a long cable is used this dropdown can be modified. 'high' and 'mid' both set 24V on-hook voltage. The off-hook loop current is set to 20mA. 'low' sets 48V on-hook-voltage.
|-
|valign=top nowrap=true|'''Ringing Voltage'''
|present on ip22/24/28 gateways only 
This topic modifies the ringing voltage used for ringing. Ringing frequency is 25Hz. 'low' sets 65Vpk/45Vrms, 'mid' sets 68Vpk/48Vrms and 'high' sets 70Vpk/49,5Vrms AC.
|-
|valign=top nowrap=true|'''Ring frequency'''
|present on ip22/24/311/411 gateways only 
Ring frequency can be set to '25Hz' or '50Hz'.
Normal ring frequency for all countries is 25Hz. The '50Hz' setting ins intended for test purposes.
|-
|valign=top nowrap=true|'''Onhook voltage'''
|present on ip29/311/411 gateways only 
Onhook-voltage can be set to '32V' or '48V'. Defaults to '48V'. Only used for test purposes.
|-
|valign=top nowrap=true|'''Loop current'''
|present on ip29/311/411 gateways only 
Offhook Loop current value can be set to values between '20mA' up to '40mA'. Note that higher values increases the power consumption of the gateway. The ip29 gateway is tested for all 8 FXS ports running 30mA offhook-loop current. If some FXS ports are configured to a higher value, other ports must be configured to less than 30mA in order to NOT exceed the maximum available power of the POE switch. Depending on the switch behaviour, drawing too much power from the POE line may result in random reboots of the gateway as a result of a power shutdown of the POE switch. In this case, reduce the amount of FXS ports configured to excessive offhook-currents above '30mA'.
The gateways with less than 8 FXS ports do not suffer from this limitation.
|-
|valign=top nowrap=true|'''Loop length'''
|present on ip311/411 gateways only 
Loop length can be set to '500m' or '2500m'.
Checking this topic to '2500m' decreases ring-trip threshold by 20% so that off-hook detection becomes more sensitive.
|-
|valign=top nowrap=true|'''Loop length'''
|present on ip28 gateways only 
Loop length can be set to 'low' for 500ft/155m or 'high' for 5000ft/1550m.
Checking this topic to 'high' decreases ring-trip threshold by 20% so that off-hook detection becomes more sensitive.
|-
|valign=top nowrap=true|'''RingTrip Threshold'''
|present on ip22/24/302/305 gateways only 
Ring-Trip threshold can be adjusted using an absolute value in milliamperes.
|-
|valign=top nowrap=true|'''Loop Current'''
|Loop current can be adjusted using an absolute value in milliamperes.
|}

Note: there is no difference between PoE and PSU powering of the IP2x.

For possible line lengths, see [[Howto:Maximum_wire_length|Maximum wire length]].

==== Recommendation for Use with long Wire Length ====
For best performance with long wires, use the following settings:
* '''Optimization grade''' low
* '''Ringing Voltage''' 49.5 Vrms (high)
* '''Loop length''' 1550 m

The setting for '''Loop Current''' depends on the terminal requirements, not wire length.

Reference12r1:Interfaces/FXS/Advanced

2015-11-16T15:52:43Z

Cmu:

The '''advanced''' settings of the analogue interfaces can be made here:

{|
|valign=top nowrap=true|'''Optimization grade:'''
|Present on ip22/24/28 gateways only 
As per default the TEL ports are optimized for low power consumption (Optimization 'high' and 'mid'). This decreases the usual on-hook supply voltage of 48V down to 24V. Most conventional phones and faxes can deal with this. In case a special phone is connected that cannot deal with this low voltage or if a long cable is used this dropdown can be modified. 'high' and 'mid' both set 24V on-hook voltage. The off-hook loop current is set to 20mA. 'low' sets 48V on-hook-voltage.
|-
|valign=top nowrap=true|'''Ringing Voltage'''
|present on ip22/24/28 gateways only 
This topic modifies the ringing voltage used for ringing. Ringing frequency is 25Hz. 'low' sets 65Vpk/45Vrms, 'mid' sets 68Vpk/48Vrms and 'high' sets 70Vpk/49,5Vrms AC.
|-
|valign=top nowrap=true|'''Ring frequency'''
|present on ip22/24/311/411 gateways only 
Ring frequency can be set to '25Hz' or '50Hz'.
Normal ring frequency for all countries is 25Hz. The '50Hz' setting ins intended for test purposes.
|-
|valign=top nowrap=true|'''Onhook voltage'''
|present on ip29/311/411 gateways only 
Onhook-voltage can be set to '32V' or '48V'. Defaults to '48V'. Only used for test purposes.
|-
|valign=top nowrap=true|'''Loop current'''
|present on ip29/311/411 gateways only 
Offhook Loop current value can be set to values between '20mA' up to '40mA'. Note that higher values increases the power consumption of the gateway. The ip29 gateway is tested for all 8 FXS ports running 30mA offhook-loop current. If some FXS ports are configured to a higher value, other ports must be configured to less than 30mA on order to NOT exceed the maximum available power of the POE switch. Depending on the switch behaviour, drawing too much power from the POE line may result in random reboots of the gateway as a result of a power shutdown of the POE switch. In this case, reduce the amount of FXS ports configured to excessive offhook-currents above '30mA'.
The gateways with less than 8 FXS ports do not suffer from this limitation.
|-
|valign=top nowrap=true|'''Loop length'''
|present on ip311/411 gateways only 
Loop length can be set to '500m' or '2500m'.
Checking this topic to '2500m' decreases ring-trip threshold by 20% so that off-hook detection becomes more sensitive.
|-
|valign=top nowrap=true|'''Loop length'''
|present on ip28 gateways only 
Loop length can be set to 'low' for 500ft/155m or 'high' for 5000ft/1550m.
Checking this topic to 'high' decreases ring-trip threshold by 20% so that off-hook detection becomes more sensitive.
|-
|valign=top nowrap=true|'''RingTrip Threshold'''
|present on ip22/24/302/305 gateways only 
Ring-Trip threshold can be adjusted using an absolute value in milliamperes.
|-
|valign=top nowrap=true|'''Loop Current'''
|Loop current can be adjusted using an absolute value in milliamperes.
|}

Note: there is no difference between PoE and PSU powering of the IP2x.

For possible line lengths, see [[Howto:Maximum_wire_length|Maximum wire length]].

==== Recommendation for Use with long Wire Length ====
For best performance with long wires, use the following settings:
* '''Optimization grade''' low
* '''Ringing Voltage''' 49.5 Vrms (high)
* '''Loop length''' 1550 m

The setting for '''Loop Current''' depends on the terminal requirements, not wire length.

2014-10-22T18:41:53Z

Cmu:

The call '''signalling''' settings of the analogue FXO interfaces can be made here:

{|
|valign=top nowrap=true|'''Disable:'''
| Disables the relevant analogue FXO interface.
|-
|valign=top nowrap=true|'''Speech Bearer Capability:'''
|Calls on the relevant interface are transmitted with Audio Bearer Capability as standard. A checked check box transmits calls from the relevant interface with Speech Bearer Capability. This only makes sense if only telephones are operated on the relevant interface (no fax machine or modem).
|-
|valign=top nowrap=true|'''Central Office Tone detection:'''
|When the FXO initiates a call, normally a audible tone is expected to be received from the central office/local PABX side. The tone detection works independantly from any country setting. When the expected tone cannot be detected within 2.6sec, then the call will be cancelled. If this tone detection is disabled, the FXO will continue dialing DTMF tones of the configured number, with a fixed delay of 800ms after hook-off.
|-
|valign=top nowrap=true|'''Establish call on line polarity reversal:'''
|When the FXO port detects a reversed polarity and the FXO port is idle, a new call wil be established. Countries that use '''DTMF CallerId''' also often use a '''Polarity Reversal''' preceding the DTMF CLIP sequence and start with AC ringing afterwards. In detail the sequence is as follows : Line polarity reversed, 200ms pause, DTMF CallerId transmission, Line polarity normal, 1000ms pause, AC ringing, pause ... . For instance Sweden is one of those countries that use DTMF CallerId combined with Line polarity reversal call establishment. If this checkmark is unchecked here, the call will miss the DTMF CallerId sequence, when established with the AC ringing. Note that this option can also be used with FSK CallerId.
|-
|valign=top nowrap=true|'''PSTN drives conversation state in reversed line polaritity:'''
|Calls from FXO->PSTN normally switch to conversation/connected state within 4seconds after dialing. If this option is checked AND the PSTN changes its line polarity while a connection to the dialed peer is established, then the FXO can recognize the reversed line polarity and switch to connected state prior to the elapse of 4seconds. Once in connected state, the FXO can detect line polarity switched back to normal polarity and assume a peer disconnect without having detected any kind of call-progress-tone (e.g. busy-tone). This is faster and in some countries the busy-tone at the end of a call is simply omitted, when polarity switching is used. If you use '''Establish call on line polarity reversal''', be shure if your provider additionally uses polarity reversals in conversation/connected state or not. If your provider does, and you miss to check this option, this might lead to strange but short and self-ending re-calls after each hook-on. This comes from the PSTN's final switch to the normal line polarity, which then leads to a wrong call. When checked, the FXO will wait for the PSTN's line polarity change at the end of the call. This behaviour is common for PSTN in Sweden.
|-
|valign=top nowrap=true|'''Volume:'''
|Sets the volume for the relevant interface, in decibel (dB), between -32dB and +32dB. No value or the value 0 is equal to the factory settings.
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|valign=top nowrap=true|'''Caller ID 1 standard:'''
|Selects the standard in which '''CallerId/CLIP''' is detected and decoded. '''CallerId''' carries the caller's phone number in case of an incoming/ringing call. This number is fed into the resulting voip call as the CGPN (Calling Party Number). Note that for this reason incoming calls from the FXO port must use ''en-bloc'' delay dialling to allow for receipt of the CLI. This may be done by registering the Port with a ''Gateway'' type PBX object and set the ''Enblock Count'' option in this object or use a route with ''Force enblock'' set in the ''Gateway->Routes'' Menu.

'''FSK CallerId''' standards can contain additional information like ''Called Line Id'' or ''Date/Time'' information. These additional informations will be dropped. '''DTMF CallerId''' only contains the ''Calling Line Id''.
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