vinodquilon
Member
Pls find the attachment of a self-explanatory telephone ring detection circuit.
The problem is that my 4N25 is not secure.
'After' four or five times of operation, it destroyed itself.
Then I replaced it with another, but same fate.
I think the protection circuit of 4N25 has no better immunity against high ring volt.
Any suggestions to rectify my problem ?
The problem is that my 4N25 is not secure.
'After' four or five times of operation, it destroyed itself.
Then I replaced it with another, but same fate.
I think the protection circuit of 4N25 has no better immunity against high ring volt.
Any suggestions to rectify my problem ?