If you look at the website for the AutoHybrid, it says the following:

AutoHybrid gives you simultaneous send and receive audio through analog telephone lines. Not just another half duplex auto-coupler, this is a full duplex AutoHybrid.

Yes, you can send and receive audio at the same time. The dual transformer hybrid is capable of 20 dB nominal trans-hybrid loss. In other words, your transmit signal will appear mixed with the receive signal, but at a level 20 dB lower than it was sent into the phone line.

The important part to read is where it says… your transmit signal will appear mixed with the receive signal, but at a level 20 dB lower than it was sent into the phone line.

This means that when you are talking to the person on the phone, you’re going to hear your own voice coming back in on the same line that you are bringing into the mixer from the telephone. Sure, it’s 20db lower, but that’s still going to give you some pretty bad recordings.

This is why we use the “Digital Hybrid” because it has technology built in to “digitally” separate the two signals. So when I do a telephone interview with the Broadcast Host, you don’t hear my voice coming in at all off the telephone line. The Brodcast Host does more than a 20db reduction….. It eliminates it from the incoming signal from the Broadcast Host into the mixer.

I hope this helps.

Cliff

Here’s a link to the blog post. I hope this helps!
http://podcastanswerman.com/jkaudio/

Cliff