Well guys, I would like to get on the school PA system to start a sort of "underground station".

I'll describe the setup:

In the main office, the desk ladies can transmit over the PA by pressing "line one" or "line two" for either the outside or inside PA. Also, a dean of students can get on the PA by doing this same method. However, there is only one physical line which runs into all these phones. This made me think that there is an extension number "line one" and "line two" are programmed to. What is the best way of getting on the PA?

†Jesus†

im taking they operate it from their phones?

im thinking, patch in another phone from a location such as a swich box just before the cables go their seprate ways so when you put power into the line it does the same thing as them hitting the button(seprate ph for out/inside can use both or one set only)

ive done that for a tx yagi at home but i cant be 100% that ittl work for a PA.

i shall confer with others snd see if i can get any more ideas.

just found this http://massis.lcs.mit.edu/telecom-ar.../phone.patches

going from what i just looked up as long as the phone of device puts the voice into electrical signals is should trigger the pa speakers. could use a wored microphone maby? puts out power- attach cord to line.



[This message has been edited by PDX (edited 01-25-2007).]

The page function on these phone-based PA's is usually tied to the last extension in the PBX. Example, if the main office phone number ends in 1800, the last number would be 1899. Therefore, 1899 would be the PA line. Sometimes, the PA line can only be accessed from phones that are programmed to allow it i.e. the phone in your homeroom class won't dial it, but the master console with the secretary or principal/dean will dial it. Theres all kinds of open phone jacks around the school, and theres a few spare parts phones in a server/electrical closet. Grab a phone from the closet, plug in, and dial away. In a traditional system (without phone/PBX interface) getting in would be a matter of some fancy rewiring, and lots of time spent unseen in the rafters.

EDIT: With some unseen access to the actual PBX box in the elec/server room, you could patch a standard phone right in, because all thats in the PBX box is where the line (from the phone) terminates and joins the Bell System wires, and a control box for network wide settings, such as Caller ID, network time, and if you've gone VoIP, the IP settings.

[This message has been edited by kelsokid18 (edited 01-26-2007).]

Thanks. Our school number ends with "000" so I will try "999". What I plan to do is use a cordless phone and plug my mp3 playing into the headset socket. That way, I won't be near it if anything goes down. Our school isn't very sophisticated, so they shouldn't have any of the "only certain phones can call it" shit, etc. Thanks again. Also, I might even use my mobile phone to do it.

†Jesus†

i wouldn't use anything traceable... but great idea on the mp3.

and oh yea dont' forget your prints.

[This message has been edited by Halvy101 (edited 01-26-2007).]

I have a sim which I found on the ground, so I should be right. Cheers.

†Jesus†

Well, if the main number ends in 000, then the number must be between 1000 and 9000, so in example, we assume that the office number is 9000, therefore, it'd be 9999. I know I said this, but the leading digit is key, most PBX's won't acknowledge the call without the leading digit.

Ok, just tried 999. No workie. Surely there must be a way to get on "line 1" or 2.

†Jesus†

Alright, so my plan of attack is to socially engineer the extension out of them. Good idea?

†Jesus†

You could just pysically tap into the line. If you didnt want to be near the tap then build a small fm reciver and transmit to it.