For whatever it's worth... Today I stumbled over the following bit of info:
Supposedly, for the DSA1000-series, the service menu is accessed by pressing: Frequency, Span, Amplitude, Trigger, Bandwidth, Sweep, Single, Continue, Trigger, Trigger. (Whew! Like it's some kind of national secret in there!)
Wondering if it's the same or similar for the DSA8-series...?