Gentlemen,

I've got this weird problem with the network analyser I posted about
recently. The problem *seems* to be noise spikes on the DC voltage
control ramp which are causing spurious spikes in the frequency domain
on the RF output when viewed on an RF spectrum analyser. The peculiar
thing is these spikes on the RF output are not random; they come and
go according to the point the control voltage has reached as it ramps
up. Curiously, I cannot see anything amiss with the ramp signal when I
check it with a scope. I'd have expected to see at least *some* sign
of instability, but it appears rock steady. I'm just wondering if an
ordinary oscilloscope is really fast enough to pick out these
transients, though. Maybe they're there even though I can't see them.
Any suggestions as to what other instrument might be better suited to
this purpose? A DSO, maybe? Or if not, optimising the settings on the
analogue scope to have the best chance of spotting them?
thanks!
--

No deal? No problem! :-D