Security & Fire Protection Systems/DSC alarm dial through Xlink BT


Like many, the only reason I still have a land line is for monitoring my security system. So, I'm looking for a way to eliminate it!

I have a DSC PC1555MX. I have a Xlink BT (bluetooth gateway, paired with a cell phone. When I connect my system to the Xlink, it dials out to the monitoring center through the cell phone. It connects then ends the call after about 18-20 seconds. It's obviously not successful and redials multiple times.

Are there any changes I need to make to the system to get this set up working? I have the installer code.

Thanks for your help and giving all of us the benefit of your experience!

Hello Keith, and thanks for your question.

The Xlink BT is new to me, so I checked the installation manual.

At first glance, it's merely a pass-through, so I'd assume it would work. But in checking the support pages on their website under troubleshooting, I found this:

Other Devices:

1. Because it uses the cellphone network, the XLink connection can not be used to transmit fax signals or alarm signals.

2. The Xlink does not work with digital office phones.

I think the issue is caused by a combination of things; first, the alarm system wants to communicate with the receiver using full-duplex. Bluetooth emulates full-duplex by using Time-division duplexing. So there could be some latency there preventing the system and receiver from being able to establish a handshake (and without the handshake, the alarm will hang up and try again, usually up to ten times). Add to this the fact that most cellular networks emulate full-duplex using frequency-division duplexing. Now we know that cellular by itself works for alarm transmission -- so I suspect it's how the Bluetooth works in combination with the cellular network.

Wish I had better news!

Best Regards,


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Dave Neuweiler


The design and application of burglary and fire systems for homes and businesses. Helping alarm owners understand how their system works. Helping to troubleshoot false alarm problems. Questions about monitoring issues.


Over a quarter century in the industry. Experience in installation, service, and monitoring centers. Training manager for a national protective services company; director of education and training for a national trade organization for for alarm dealers.


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