[time-nuts] What is the best way to multiply a 10 Mhz

Mike Feher mfeher at eozinc.com
Tue Dec 21 20:13:53 UTC 2010


The 6 mixer scheme was my first thought for lowest PN. That way you do not
get 20logN, but you just get the RMS sum of the noise power each time. That
would be 3 dB to get to 20 MHz, and, each time the sum becomes less than 3
dB, as the highest frequency dominates. It would only degrade approximately
a total of 10 dB vs. the 17 dB from a regular times 7. Regards - Mike

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-----Original Message-----
From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On
Behalf Of Bill Hawkins
Sent: Tuesday, December 21, 2010 2:55 PM
To: 'Discussion of precise time and frequency measurement'
Subject: Re: [time-nuts] What is the best way to multiply a 10 Mhz

So, two doublers for 40 MHz and a tripler for 30 and then
mix to get 70? What happens to phase noise when you do that?
Is it as bad as a PLL?

Seems like you ought to get adequate harmonic rejection.

What about six mixers to get 20, 30, 40, 50, 60, and 70 MHz?

Chips and tank coils are cheap, no?

Bill Hawkins


-----Original Message-----
From: Burt I. Weiner
Sent: Tuesday, December 21, 2010 1:39 PM

It would seem the most jitter free way to do it would be to simply 
multiply it up like we used to do.  Some reasonably Hi-Q LC circuits 
could make a nice flywheel and filter out other signals at the same 
time.  Once you have it to the desired signal frequency you could 
condition it to clock your DDS.

Am I missing something here?  Wouldn't be the first time, ya know!

Burt, K6OQK


>Subject: Re: [time-nuts] what is the best way to multiply a 10 Mhz
>         signal?
>
>
>On 21/12/10 16:35, Stephen Farthing wrote:
> > Hi everyone,
> >
> > I want to multiply the output from my Efratom 101 (10Mhz) to clock a DDS
at
> > 70 Mhz. Has anyone tried this?
> >
> > Regards,
> >
> > Steve G0XAR



_______________________________________________
time-nuts mailing list -- time-nuts at febo.com
To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.




More information about the time-nuts mailing list