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Cursitor Doom[_4_] Cursitor Doom[_4_] is offline
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Default Noise on VCO voltage ramp

On Sun, 12 Jan 2020 17:17:04 -0500, Phil Hobbs
wrote:

Frequency domain glitch? You mean a discrete spur?
A glitch is a transient time-domain animal.


I could have put it better I guess. What I mean is I'm seeing thin
spikes in the RF output spectrum of the VNA at other frequencies than
the desired one. I'm guessing these spikes are the result of unwanted
transient voltage spikes present on the DC VCO control voltage which
sweeps the RF output frequency from 4Mhz through to 1.3Ghz.

A DSO can save a single
instance, or (with averaging) ignore the noise and asynchronous
background and just reproduce the glitch itself.


Well, Jeff has posted some advice for me on that aspect which I intend
to try out tomorrow using my Tek DSO which is probably much better
suited to the task than the analogue one I've hithertofore been
using..
--

No deal? No problem! :-D