The new Index QRP+ has been daring me to measure its spectral output - and the ULTRA's latest firmware supports storage of the displayed traces as a bitmap file, saved to an included 32GB MicroSD card.
A combination of Elecraft's bi-directional coupler and my step attenuator knocked its 10W output down by 40dB, to 1mW.
For some reason, I saw no harmonics on 160, 80 or 40 meters so I brought out the big (comparatively) Rigol. Same thing - and something I need to investigate. Surely, there are harmonics being generated on these bands...
Incidentally, I looked at the other bands on the Rigol as well - the displayed traces were practically identical to those of the tinySA ULTRA.
So why buy a Rigol instead of the tinySA?
Two reasons: 10Hz minimum RBW, much faster scan times for a given RBW and the Rigol has a built-in tracking generator (this allows it to perform some of the functions of a VNA).
a CW op, I'm not really interested in a radio's IMD performance on SSB
where a high RBW is necessary and I already have a nanoVNA to perform
the Rigol's tracking generator functions.
However, my (absolutely mint) Rigol is for sale ($700 shipped, US only).
But on to 30 to 10 meters on the QRP+:
No so great on some bands...