Learning to use a Spectrum Analyzer

[tggzzz]

... I've seen a lot of "professionals" (myself very much included) do some ... unadvisable ... things with test equipment.

Oh no, never. Never ever ever. 

Most professionals have a pretty good idea of what powers they are going to be measuring and simply add an appropriate (external) pad where needed.  I also know quite a few customers who will use an RF power sensor when in doubt, since blowing up one of those is less costly (but again, it's still pretty rare).

Another issue is where the UUT is grossly faulty, e.g. has DC on the signal.

If you're just interested in learning how to operate a spec an, an easy and very safe way to get test signals is just to get a cheap antenna and look at the FM broadcast band or some cellular or ISM band (e.g. 2.4 GHz, etc.).  Lots of signals to practice on, no expensive equipment needed, and essentially zero chance of damaging anything. 

Other sources are

• plain old signal generators, looking for harmonics and phase noise
• digital signals, especially PRBSs, and looking for where the 20dB/decade becomes 40dB/decade thus hinting at the transition times. Almost certainly needs a pad and DC block!

[pdenisowski]

Another issue is where the UUT is grossly faulty, e.g. has DC on the signal.

Indeed .  But most "professional" analyzers can / should tolerate relatively high levels of DC at the inputs - up to 50 VDC in the case of all our spec ans

Almost certainly needs a pad and DC block!

Yes, these are cheap insurance no matter what.  I have a huge assortment of attenuators and if I were given a "mystery signal" to look at, I would probably start out with one of the larger pads   An external step attenuator might be another option.

[VSV_electron]

Thanks much for all your replies! Just exactly what I wanted to know.