Hi
> On Aug 4, 2020, at 3:50 PM, Poul-Henning Kamp <[email protected]> wrote: > > -------- > Bob kb8tq writes: > >>> I have not given much thought to A11 yet, and I do find a certain >>> elegance in the wien-bridge approach. It is worth noting that the >>> actual heaters run of the unregulated supply, when I stabilized >>> that, A11 worked less hard. >> >> The AC bridge approach certainly worked well 'back in the day'. > > Actually, what I like is that it makes it possible to decide the > frequency spectrum of the inevitable noise, and in this case put > it up around a kilohertz where it is a lot less likely to cause > trouble. > > The "modern" approach to that is to modulate or dither with a > good long PRNG to whiten the noise, and while good in theory, > it is not _that_ easy to get right in practice. Of course one could simply cave in to the fact that for the sort of gain required here, a pure DC controller works quite well. I know - that takes all the fun out of it ….. Bob > > > -- > Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 > [email protected] | TCP/IP since RFC 956 > FreeBSD committer | BSD since 4.3-tahoe > Never attribute to malice what can adequately be explained by incompetence. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
