Lync Hacker: Step by Step Native #Lync DoorBell Using #snom PA1


Lync administrator Daryl Sensenig is using full Enterprise Voice at Tents for Rent and wanted to extend Lync as far as possible so he put his hacking skills to use to turn the snom PA1 into a complete native Microsoft Lync door bell. I appreciate Daryl giving permission to repost his solution and if you have any ideas to improve or if you have a low cost external/weather proof door bell to suggest, comment below.  Here is what he did…

I spent a lot of time figuring out how to build a door phone for Lync 2013. The documentation was very poor and fragmented. So, I thought I'd share how I did it so that others could benefit.

  1. I started with the Snom PA1 and updated it to the UC edition firmware.
  2. I purchased an AIPHONE LE-A and a mini mic from Amazon.
  3. I setup a ring group for the doorbell in Microsoft Lync
  4. I entered the UC account data into the PA Web UI.
  5. I setup speed dial "1" to be the doorbell ring group.
  6. I set auto dial to "after 2 seconds" It is located in Advanced > Behavior > Auto Dial
  7. I set it to auto answer in Identity 1 > SIP > Auto Answer. This allows me to call it if necessary.
  8. I inserted the mini mic into the "mic in" jack.
  9. I opened the AIPHONE and soldered wires from the AIPHONE speaker and connected them to the "Speaker" connectors on the PA1.
  10. I connected the wiring harness to the KBD (keyboard) port of the PA1 and soldered the white and purple (6 and 7) wires onto switch on the board in the AIPHONE. Thus by pressing the button on the AIPHONE, it dials the number 1 and after 2 seconds, speed dials my doorbell ring group.
  11. I connected the wiring harness to the I/O 2 port of the PA 1. The black wire is ground, brown is always 12 V (good as a power supply for a relay). Yellow is pin 3 and purple is pin 4. These can be connected to a relay for a door strike, door opener and etc. I haven't done this yet, but I plan to. The first PA1 unit I had did not supply 3.3V to pin 3 and 4 when activated. So, I had to get another unit.
  12. You can turn these pins on by dialing 3# or 4# when in a call to the PA1. You can also turn them on in the web UI: Preferences > PA1 controls > Pin 3.

There were numerous other steps and dead-ends that I ran into before I came up with this simplified list. I've eliminated all my "wrong" steps to keep it simple.

Please let me know if I've missed anything. I hope this is helpful to those who would like to do the same thing.

My total costs were:

  • $105 for the PA1
  • $24 for the AIPHONE
  • $5.05 for the mini mic
  • Total out of pocket $134.05
  • Lots of time, hassle, forum reading, posting and soldering

My next project is an outdoor doorbell. I'm looking for an affordable weather resistant door bell. If you have any ideas, please post.

Connecting the Call Switch (below)


Call switch connection


snom PA1 and


snom PA1 Connections



More discussion:


  1. Great post about doorbell and all the steps you have mentioned is really interesting and knowledgeable. Thanks for sharing this great.

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  2. Hi! you are really share the best idea for doorbells and i like your blog but allami provides the special materials and aluminium doorbell and doorphones . Thanks for sharing!