Agilent E4430B signal generator AM modulation is funny

[ErnieEngineer]

 

Just purchased a E4430B and decided to do a quick check with the AM modulation. It looks weird, with extra images!

NOTE: the picture is for when I used internal modulation, but external modulation is the same (1Vpp AC coupled, 50kHz)

Is there any way to fix/adjust this?

My other generator (N9310A) is shown for comparison.

[VK5RC]

Is it just clipping? Does it go ok at say 80% modulation?  At 100% aren't you only a whisker away from over modulation?

[ErnieEngineer]

Excellent point! When I switched to 10% it looks perfect. Why would the other generator not have this at 100% tho?

It looks just as ugly at 80%, anything above 20% really.

[VK5RC]

Can you see the waveform on a scope,  and see if the 50% as 'dialed in" is correct?
Mixers are the' devils work'.  If you know what I mean,  very difficult to get it right re harmonic suppression,   3 order intercept etc. 
Hopefully some of the serious rf guys will chip in shortly,  best of luck.