Full Duplex on a 6400M

K9YK

I've got a 6400M and I'm trying to figure out how full duplex is supposed to work. I have 2m and 70cm transverters, but lets take that completely out of the conversation.

I've got slice A set to 6m and slice B set to 20m. They are both set to TX on the XVTA port and both set to receive on RXA. I'm generating a low level signal with my HP 8924C on 50.174 and injecting it into the RX A port. Nothing is connected to the XVTA port, and my Tune power is set to ZERO.

Full duplex is turned on. Slice A on 6m shows my injected signal on the RXA port and Slice B is set to TX on 20m. If I hit the tune button, the RX signal on Slice A goes away. WHY??? What am I doing wrong that's blocking the RX on 6m while TXing on 20m?

Here's a short video that shows what's happening:

https://www.youtube.com/watch?v=IgBghU-4x6o