Hi Bob thank you The reason for the original question was because I am using a leobodner reference but I require 27 mhz for the LNB 25 mhz for the phase lock loop at Ghz and 10 Mhz for the IF receiver so the leobod unit although being exceedingly good it only has 2 outputs so I thought of 5 to 10 and 5 to 25 add ones might be the answer
my spectrum analyser uses a 100 mhz reference so I realise your opening line Please can we talk of line as I do want to learn about phase noise Paul -----Original Message----- From: time-nuts [mailto:time-nuts-boun...@lists.febo.com] On Behalf Of Bob kb8tq Sent: 12 September 2019 23:19 To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] 5 Mhz to 10 Mhz and 25 Mhz Hi If that's the objective then the correct answer is: "none of the above" :) For a low noise microwave chain, you want to go as high as you can with a crystal oscillator in the first step. That gets you into the 100 to 200 MHz range as the first step up from your low frequency standard. There are a lot of reasons why. Bottom line is that it's how you get the best noise out of the chain. Depending on the offset involved, and what you are comparing to, it may be better by as much as 20 to 40 db. Bob > On Sep 10, 2019, at 11:19 AM, Paul Bicknell <p...@bicknells.f2s.com> wrote: > > Hi Dave I posted the question as I am not up to speed with the latest > solutions > But I want the lowest phase noise that is easily possible so you might be > correct as it is to lock up a 10 Ghz receiver but later for a 120 Ghz > receiver > > Regards Paul > > > > -----Original Message----- > From: time-nuts [mailto:time-nuts-boun...@lists.febo.com] On Behalf Of Dave > B via time-nuts > Sent: 10 September 2019 17:40 > To: time-nuts@lists.febo.com > Cc: Dave B > Subject: Re: [time-nuts] 5 Mhz to 10 Mhz and 25 Mhz > > On 10/09/2019 17:00, time-nuts-requ...@lists.febo.com wrote: >> Re: [time-nuts] 5 Mhz to 10 Mhz and 25 Mhz > > Why not just create a comb of frequencies based on the 5 MHz input, then > filter and extract the 10 and 25 MHz signals you want, amplify and > distribute as needed? Going the PLL route seems like a large hammer to > crack a small nut. > > Unless you want a free-running signal if the incoming 5 MHz vanishes... > > Dave G0WBX. > > > Created on and sent from a Unix like PC running and using free and open > source software: > > _______________________________________________ > 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 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. ----- No virus found in this message. Checked by AVG - www.avg.com Version: 2016.0.8048 / Virus Database: 4793/15884 - Release Date: 08/14/18 Internal Virus Database is out of date. _______________________________________________ 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.