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How SQLphone Transfers Calls

Basics

SQLphone does not actually transfer calls itself. Instead it requests your PBX to transfer a call. SQLphone mimics the way a human operator would transfer a call using a standard phone: press the phone Recall button; dial the transfer-to number; hang-up to complete the transfer.

So your PBX needs to support call transfer using hook-flash or earth-recall signalling (most PBX’s do support this). Some Telco’s can also provide a call transfer service if you are not connecting SQLphone to PBX lines.

You don’t need to reserve SQLphone lines for transferring calls, since the call transfer takes place within the PBX. Each SQLphone line operates independently of other lines, one line cannot influence the operation of another line.

External transfer

Transferring a call to an external phone number is handled the same as transferring to an internal extension. However, external call transfer is usually a feature that must be separately configured on you PBX.

SQLphone flowchart

To add call transfer to your flowchart, add a Transfer box to your flowchart. Then setup the box properties. SQLphone supports 2 types of call transfer...

Blind call transfer

Use this transfer type when your PBX supports blind transfer. You should setup your PBX to queue transferred calls, so the caller never gets a busy tone. After SQLphone hangs-up, the caller is transferred to the dialed extension.

SQLphone performs these functions:

As soon as SQLphone hangs-up, the caller is connected to the dialed extension number, and the SQLphone line is freed-up to handle more incoming calls.

Monitored call transfer

Use this transfer type when you want to play a message to the transfer-to extension, before handing over the call. Can also be used to detect when the transfer-to extension is busy, or not answered after a configurable time period.

SQLphone performs these functions:

As soon as SQLphone hangs-up, the parked caller is connected to the dialed extension number, and the SQLphone line is freed-up to handle more incoming calls.

Cancel monitored call transfer

Use this transfer type to recover a monitored call transfer, which failed (generated a NoPhone or NoReply event).

SQLphone performs these functions:

 


Troubleshooting

If call transfer is not working, the first thing to establish is whether your PBX supports call transfer on the IVR lines. Do this using a standard phone handset on one of the IVR lines as follows.

Standard phone test

If the call cannot be successfully transferred, please check your PBX configuration.

SQLphone settings

If the IVR lines can successfully transfer calls using a standard phone handset (as above test), but SQLphone cannot transfer calls, the most likely cause is a hook-flash duration mismatch.

You can change the SQLphone Runtime hook-flash duration (along with other dial-out settings) as follows:

The default is 80 milliseconds which works with most PBXs. We suggest you start with 100ms and work down in 10ms steps. You might want to increase some of the other DTMF timings for an older PBX.