Old bpt intercom to VoIp

[Covert_monkey]

Hi All,

I tried searching for this but couldn’t find any information. I want to try and connect my old bpt intercom to Linksys pap2t

https://www.cisco.com/c/dam/en/us/td/docs/voice_ip_comm/csbpvga/pap2t/administration/guide/pap2t_user.pdf

man’s maybe a raspberry pi to be able to buzz people in when I am not at home. Changing the entire building intercom is not a possibility.

Has anyone tried this before ? I will try and find the model number of the main unit.

 

[sparkymarka]

That’s for a standard telephone …..not an intercom system ….you could use an IT200 if your bpt system is a 200 system to try and interface with that unit but they are not cheap ….but it’s not guaranteed to work ….

 

[Covert_monkey]

Well my handset closely resembles BPT E/200P1 the button layout is a little different.

is this what you mean ?
https://www.bptuk.net/bpt-it-200-telephone-interface

 

[RandomGrinch]

Hi,

I'm sure there are many possibilities, but the first idea that comes to mind, without any thinking (and this definitely is not the best ) :
If you are interested in RPi's, why not connect a relay linked in parallel to the door open button, and control it remotely through a web page?
http://www.reuk.co.uk/wordpress/raspberry-pi/simple-raspberry-pi-relay-control-over-the-internet/
Ignore the speech on the intercom (although the RPi could handle this too!), and just get your visitors to phone you when they are at the door.
I hope that gives you some ideas!

Edit: or a simple IoT relay like a Sonoff, would be an off-the-shelf solution. Although there would be security implications for both these solutions!

 

[sparkymarka]

Unfortunately your only guessing what you have to start with …it may be another system that just happens to use BPT handsets eg tynetec

 

[Chri]

Interesting topic!

I was looking for something similar but didn't get to a conclusion yet.
The idea is to use DoorPI on a PI Zero
- Door opener and bell signal can be handled via the GPIO
- For Mic and audio out a usb sound card or pi audio hat is needed

My problem as an electronic noob is how to connect the BPT "wires" correctly. I think all the information needed is already somewhere out there but not in a single blog post

 

[RandomGrinch]

As above, the door opener should be simple a relay connected in parallel with the door open button should do.
The Pi's GPIO are only 3.3V, so the easiest way to connect is via a relay hat.
A Pi audio hat could connect straight to the audio lines as you say and should provide isolation from the intercom circuits.
The bell signal might need some thinking about though, possibly needing an opto-isolator before connection to the Pi.

 

[Chri]

I found a arduino project which used a PC814 behind a 1k resistor to connect the bell to the GPIO.
for the door opener there are quite some projects out there that use a relay sure, question is if diods are needed if we connect it parallel to the existing handset.

For the audio I'm not sure if you can connect it straight to the audio lines or if you need a transformator and maybe also amps.


I'll order a PI and test that.

Actually it's not about saving money but I assume there are quite some people out there who would benefit from a small device that you could plug simply plug in front of the handset. Should be quite common that one is unable to change the existing installation but would e.g. like to unlock the main door so packages can be placed in front of the apartment door etc.