I what they are on the 401(same as the DRS-922 and DSR-805 C\Ku band 4dtv).... options 6-0-5...for diagnostics screens and options 6778,I think.

What are the hidden codes for the 505?

option 6-4-9-8-8 is one. Forgot the other one...

6-4-9-7-7-1 for diagnostics.