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<DIV>>If half-duplex audio is good enough for you, sure.</DIV>
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<DIV><FONT face=Arial size=2>You've lost me there. I am not aware of a
modem that is for sale today that is half duplex. (OK some support a couple of
minor half duplex modes). All state of the art modem protocols send and
receive simultaneously using the full 300 - 3000 Hz bandwidth in both directions
with adaptive equalization and echo cancellation to make it work, which is
pretty much what a voice circuit need. There are two differences: 1)
The response and quality of a current modem must be considerably higher than
what is needed for voice use or it would never achieve the throughput expected
of it, and 2) the adaptive equalization algorithm is designed around modem
specific techniques. The latter is (especially for a softmodem) a software
issue, not a hardware limitation.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>>Only a fraction of the
hardware available is actually capable of full duplex audio.<BR>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Absolutely not the case. Particularly the
softmodems (the most inexpensive) contain little else than what is required for
placing and answering full duplex audio calls. Everything else is in the
driver. The OP is 100% correct, that they would be an excellent candidate
for FXO use in low volume applications.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>>What it really comes down to
is a value proposition:
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Quite true. This is the real issue. As
mentioned, these drivers require considerable skill and knowledge to
write. While there is no doubt that the result would be very cost
effective, the business model is lacking. The modem manufacturer is going
to see the potential market for this as somewhere down in the noise compared to
their normal modem sales, so isn't inclined to invest. A third party
developer with the skills would have a difficult time recouping development
costs (let alone any profit) because they don't control the hardware, and
therefore have no leverage. A user with enough volume to justify paying
for the development (or doing it if they had the skill) probably has enough
volume to use T1s instead. If everyone that could benefit from using
a modem card were to pitch in $10 towards the development, it would probably be
quite possible. But how to make that happen?</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Wilton</FONT></DIV>
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