Re: [time-nuts] Symmetricom 023-63008-07 5MHz Crystal Oscillators
Hi One interesting thing to do with good / cheap OCXO’s: If you multiply an OCXO from 5 to 10 MHz, noise goes up by 6 db. If you mix two independent 5 MHz OCXO’s to get 10 MHz, phase noise goes up by 3 db. The same thing happens with ADEV, multiply has no impact. Mixing *should* only get you sqrt(2) of the original ADEV. ( This assumes the ADEV is not coming from a common source like temperature …..) Indeed you could go crazy with hundreds of OCXO’s. Practical setups might run 2, 4, or 8 devices. If indeed they are 20 to $30 sort of parts, four get you somewhere around $100 for the OCXO’s. Mixers / filters / pc boards might double the total cost. Mixing 4 would cut the ADEV by two and drop phase noise by 6 db compared to a multiply. If you had an ideal divider, you could indeed get 6 db better noise at the original frequency. Compared to chasing “unobtanium” grade OCXO’s this could get you low parts in 10^-13 without spending years loosing out on kilo-buck level auctions. ( …. and possibly getting one that does not work ….). Taking the plotted data, you might hit 2x10^-13 at 10 seconds with 4 or 8 OCXO’s. Would you break 3x10^-13 at 1 second? Only way to know is to try it :) Indeed, there are a variety of ways to do the combination. Each has it’s benefits …. Bob > On Jan 22, 2020, at 2:51 PM, cdel...@juno.com wrote: > > Hi, I'm testing some of these for a project and they have pretty good > performance! > > Attached is a plot of a very nice one. > > Most are in the mid to high 10-13th Allan Deviation! > > Need to cover to prevent drafts while testing for best results, I just > lay a piece of bubble wrap over the unit on the bench. > > 800ma cold 300ma warmed up 5Mhz sine wave out SC cut with EFC input an > +5v Ref output. > > Very fast warmup! > > Can be adjusted plus minus 1.5Hz, would make a nice offset oscillator for > a DMTD (1Hz offset) > > Also listed as 023-63008, eBay has some and if you Google it there are > some direct sellers. > > Does anyone know what these were removed from? > > Be interesting to know as there seem to be quite a bunch out there! > > Cheers, > > Corby<885ad.bmp>___ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] Horowitz & Hill - "The X Chapters" - shipping now
Hi, On 2020-01-22 19:02, Charles Steinmetz wrote: > Amazon (US) is shipping Horowitz & Hill's "The X Chapters" now; I > received mine yesterday. Mine arrived this afternoon. Thanks for the recommendation. Now, I've not had much time to look at it, but for sure, it seems to be more of the same in a good way. One little sub-chapter is about the spikes from rectifying diodes. It is really nothing new, it's been known in the field for a long time, but it is good to see it treated here. The field of differential amplifiers is covered more deeply for instance. Looks interesting. If I had time I would read more out of v3 and x, as in all, but I cannot dedicate that much time to it. Cheers, Magnus ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] Horowitz & Hill - "The X Chapters" - shipping now
The extra material that did not make it into The Art Of Electronics 3rd ed. because that book weighs already 2.3 Kg. It filleth the community with bliss and is the current bestseller, just 3 days available. < https://www.amazon.de/Art-Electronics-x-Chapters/dp/1108499945/ref=sr_1_2?__mk_de_DE=%C3%85M%C3%85%C5%BD%C3%95%C3%91=x+chapters=1579717926=8-2 > cheers, Gerhard ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] Horowitz & Hill - "The X Chapters" - shipping now
And what, precisely, are “The X Chapters”? DaveD > On Jan 22, 2020, at 13:02, Charles Steinmetz wrote: > > Amazon (US) is shipping Horowitz & Hill's "The X Chapters" now; I received > mine yesterday. > > Best regards, > > Charles > > > > ___ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
[time-nuts] Horowitz & Hill - "The X Chapters" - shipping now
Amazon (US) is shipping Horowitz & Hill's "The X Chapters" now; I received mine yesterday. Best regards, Charles ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
