/Projects/Phone call alert

After putting together this little device, you must enter programming-mode to learn some phone numbers which this module will call after detecting an input on it's sensor pin.

After programming just supply power to the device. After pressing the button "Pokreni dojavu alarma" it will start to dial (tone or pulse, depending on the jumper setup). When the phone call is succesfully established, the called party should press pound key "#" to stop the device from calling another number or again.

UPDATE: Source code is now available for download!


You should put a sensor instead of button "Pokreni dojavu alarma".

Programming the numbers

- press the "program" button
- pick up the phone that is connected to the same phone-line as this device
- punch-in first number and then "*" key
- punch-in then next number and then "*" key
- punch-in the rest of numbers, if more, and finalise with "*#" (example: 061123123*061456456*#)

Please note: The device will learn 64 characters/digits including * and # keys.


Author (sent by): Trax

Download counter: 16,881

Rating: (2.95, votes 3403)


Date: 17-02-2007

Lokalna verzija ove stranice: Phone call alert


Bookmark and Share Comments (67)

comment [27]

I have record the exp. with video I will upload it, Would you mind watching the video ? I have connected the two line of the circuit to the line of the telephone , not the telephone it self. Is it correct ? please replay, thanks

comment [26]

When you press numbers on the other phone, the LED should register it turning OFF (or ON, I can not remember). does that happen? if not, then Audio signal is not being passed to MT8880 IC through the transformer. OR the crystal you used on MT8880 is not operating properly!
IP: n/a

comment [25]

I've connected the ckt to the telephone line once I turn it on the LED started flashing, then I pressed PROGRAM button the LED glowed I punch in the number then I pressed (* #); After that I pressed the ALARM button, but nothing happened. I checked the connection it was correct, I don't know what to do now can you tell me please??

comment [24]

Yes, the operation is correct. Don't worry, it will work OK. The diodes are two Zener diodes ZD 1V (in circuit schematics) and they are located at the bottom of MT8880 IC (in the pictures). The circuit will work without these diodes OK, but it is best that you use them.
IP: n/a

comment [23]

Thank you so, last night I have connected the circuit; but I didn't connect it to the telephone yet. once i turn it on a led glows, when I press program button the LED start flashing; Is the operation like this correct?? also sir there are two Diodes are connected in the 8880 to the left they are not shown in the schematic ckt diagram would mine telling me where can I put them please, Im really thankfull.

comment [22]

The micro-controller program is written in MPASM (assembler). The relay used is NO (normally open).
IP: n/a

comment [21]

please anyone tell me the program in which micro controller language is written?? Also the relay is it (NL) or (NO) if short description is provided it will be so good please reply!!

comment [20]

Tako je, samo treba isprogramirati PIC16F84 i to je to. Uredjaj radi provjereno - ako ga dobro sastavis.
IP: n/a

comment [19]

da li samo treba programirati ovaj PIC16F84, pronasao sam shemu programatora i skinio program za programirati pod nazivom NTPicprog , sada me zanima prije nego pocmem sve sklapat da li ce to da fukcijonira? hvala na odgovorima
IP: n/a

comment [18]

Thank you very much for this well done and hope the best for you
IP: n/a

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