davepusey
Member
I'm currently building a Caller ID interface for my PC, so that I can log/announce incomming calls on the network.
To provide isolation from the telephone line I am using a 600ohm 1:1 transformer. The datasheet provides a recommended circuit...
**broken link removed**
I have built this part of the circuit and it works well, but the problem is the capacitor (highlighted in green) is such a large value that I cannot obtain from anywhere. The only thing I could make it were three old 2.2uF capacitors in parallel, but these are quite bulky.
**broken link removed**
I'm hoping someone can advise me if I can use a much smaller value capacitor so that I can reduce the bulk and also make it easier for others if I decide to publish my circuit or make kits of it in the future.
I'm also sure i read somewhere that the capacitor will also act as a high-pass filter, with smaller value=higher frequency and vice versa. Is this correct?
To provide isolation from the telephone line I am using a 600ohm 1:1 transformer. The datasheet provides a recommended circuit...
**broken link removed**
I have built this part of the circuit and it works well, but the problem is the capacitor (highlighted in green) is such a large value that I cannot obtain from anywhere. The only thing I could make it were three old 2.2uF capacitors in parallel, but these are quite bulky.
**broken link removed**
I'm hoping someone can advise me if I can use a much smaller value capacitor so that I can reduce the bulk and also make it easier for others if I decide to publish my circuit or make kits of it in the future.
I'm also sure i read somewhere that the capacitor will also act as a high-pass filter, with smaller value=higher frequency and vice versa. Is this correct?