Telephone Supervisor "Ringing not detected"

[riteshjain_82]

hello sir, i am from india...
i have build a project of "Telephone Supervisor" published in dec-2005
it working perfectly and fine ..
but i am facing only one problem is that the ringing is not detected by it..
i think there is something standered problem or not sufficient ringning voltage at across ild250(opto)..
kindly guide me ..what modification or changes i should do(can i decrese the R2,R5,R10) ..
thanking you
Ritesh jain

[riteshjain_82]

why there is no support
please guide

[Guest]

This forum is intended for communication between readers and is not necessarily read on a daily basis by Elektor editors and lab staff. Technical problems with specific published projects are best communicated directly to the editorial staff, this will yield a personal response.
We will nonetheless attempt to answer your query.

The circuit does not detect the ring signal, which is copied to enabled inputs in the circuit. The first extension to answer an incoming call is effectively connected to the line. We have no idea how many phone sets you have connected to the phone line, or the maximum number of telephone sets allowed on a telephone line in your country. Hence the author’s published recommendation to limit the number of devices to two phone sets and one modem.

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