[time-nuts] Any simple way to get 200 MHz from 10 MHz?

Jim Sanford wb4gcs at wb4gcs.org
Sun Sep 28 08:14:18 EDT 2014


Dave:
Check out w1ghz.org.

Paul has some designs (and boards) that can lock different oscillators 
to a reference.  He uses a long time constant to manage phase noise.

His objective is good enough performance to generate GPS stabilized LOs 
suitable for weak signal narrow-band amateur radio communications.  I 
would suspect that such would be more than sufficient for what you are 
trying to do.

For that matter, in your application, multiplication of a really good 
oscillator could probably be good enough, although pay attention to the 
filtering to keep out harmonics you don't want. Given this, Paul's setup 
may be simpler to execute.

Good luck, and please share what you decide.

Jim
wb4gcs at amsat.org

On 9/28/2014 6:24 AM, Dr. David Kirkby (Kirkby Microwave Ltd) wrote:
> I am looking for a quick & simple way to create a frequency of 200 MHz from
> 10 MHz.  Actually 100, 200, 300 or 400 MHz would all work,  but 200 MHz
> would be my preference.
>
> The input will be around 0 to +10 dBm and the output needs to be about +13
> dBm.
>
> I did think of a x5 & x4 frequency multipliers and amplifiers from
> Minicircuits, but I don't know if the increase in phase noise might be a
> problem.  The truth is I don't know how good it needs to be!
>
> I am trying to find a way of building something that will allow my HP 8720D
> VNA (50 MHz-20 GHz) to work below 50 MHz. My idea was to generate a 200 MHz
> local oscillator to feed a mixer.
> I was thinking of making it so as the VNA sweeps from 200.01-250 MHz, it
> possible to analyse a DUT over the frequency range 0.01-50 MHz.
>
> Having the  an integer multiple of 100 MHz is good, as it makes reading the
> VNA easier. It is simpler to use if the VNA display shows the frequency 200
> MHz off than if its 212.5564 MHz wrong.
>
> I would rather not have to program anything to do it,  but maybe a VCO and
> PLL is the only sensible approach.
>
> I can't seem to find an off the shelf solution which I can lock to a 10 MHz
> reference.  There are plenty of 200 MHz oscillators around based on a TCXO,
> but I can't lock them to the 10 MHz oscillator the VNA uses.  Maybe someone
> knows of a device I don't know of.
>
> Dave.
> _______________________________________________
> 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.
>


---
This email is free from viruses and malware because avast! Antivirus protection is active.
http://www.avast.com



More information about the time-nuts mailing list