-------- In message <20180221163511.b8d6eec26415fe16e66e44f1@kinali.ch>, Attila Kinali w rites: >On Tue, 20 Feb 2018 09:36:49 -0700 >Mark Goldberg <marklgoldberg@gmail.com> wrote: > >> I don't know anything about these devices, but for TCXOs, the power supply >> noise significantly affects the phase noise of the output. An LM317 is not >> well specified for noise and I expect is is orders of magnitude worse than >> something like an LT3042 low noise regulator. > >It's >30dB for broadband noise, according to Gerhard Hoffmann's measurement: >https://www.flickr.com/photos/137684711@N07/24070698809/in/album-72157662535945536/ Just to point out that you are rapidly heading down a blind alley from where this topic started: I was talking about driving the single-transistor UHF generator which ionizes the Rb in the lamp, so far I have not even established if this voltage affects the HP5065 performance in the first place. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 phk@FreeBSD.ORG | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence.

			Attila Kinali

On Wed, 21 Feb 2018 15:37:53 +0000 "Poul-Henning Kamp" <phk@phk.freebsd.dk> wrote: > I was talking about driving the single-transistor UHF generator which > ionizes the Rb in the lamp, so far I have not even established if > this voltage affects the HP5065 performance in the first place. Oops... sorry, I missed that piece of context. Yes, it is very unlikely that the noise of lamp power supply would affect anything. At most, I could imagine that the frequency drift of the lamp oscillator could maybe have some effects, but even that is rather unlikely or swamped by other disturbances. Attila Kinali -- It is upon moral qualities that a society is ultimately founded. All the prosperity and technological sophistication in the world is of no use without that foundation. -- Miss Matheson, The Diamond Age, Neil Stephenson