Mauricio Jancic wrote:
> Can you please explain to me what is the difference between a "wet"
> and a "dry" interface?

There is a nifty 20 page modem design guide for the CMX868 located here:

http://www.eetchina.com/ARTICLES/2002OCT/A/2002OCT15_ICD_BD_NTEK_ID_AN01.PDF

It mentions "dry" transformers and shows how to make a line interface
(one transistor, 4 resistors, 1 cap, and a zener diode) that sinks the
proper amount of current to keep the phone off-hook, but keeps the
transformer "dry" with a blocking capacitor.

michael

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