[hpsdr] Alex relay chatter

[Bob Cowdery]

Hi,
I've noticed that the Alex TX filter relays chatter if I do not set 
duplex and move the RX frequency away from the initial frequency setting 
such that there is an automatic change of filter. Its like the TX 
filters keep changing between the two frequencies at quite a frightening 
rate. Never noticed this before as I usually run remote and it seems not 
to affect the RX path.

To add a bit of context. I set all the NCO frequencies to 7.1 default 
during initialisation and then if duplex is not set on RX tune I keep 
NCO-0 and NCO-1 in step. If duplex is set I just change NCO-1 on RX 
tune. The duplex bit is also set/unset in the CC bytes. This occurs 
running just one receiver and no transmitter.

I know I need to trace this through the firmware but its a while since I 
did that and a change of computer means I'm no longer set up and can't 
really remember what version of Quartus I need. I remember having a few 
false starts last time with the wrong versions.

Any help appreciated.
73 Bob G3UKB