[time-nuts] NIST frequency doubler
SAIDJACK at aol.com
SAIDJACK at aol.com
Mon Jul 9 23:27:20 UTC 2007
In a message dated 7/9/2007 01:59:46 Pacific Daylight Time,
bruce.griffiths at xtra.co.nz writes:
>It just an RF bypass capacitor to ground.
>This circuit was embedded in a very small section of a much larger
>paper, so its difficult to find.
>You may even have read the paper and not have noticed the mixer circuit.
>The resistor from the centre tap to ground is selected so that the peak
>drain current is around 28mA or so when the RF is applied
>RF input ~ 13dBm.
>Input transformer 1:4 turns ratio (or thereabouts) centre tapped secondary.
>Output transformer 2:1 turns ratio (or thereabouts).
>RF bypass capacitor depends on input frequency typically 100nF or so.
>Bruce
Hi Bruce,
nice circuit. Many questions:
I wonder how well it works to get a 5MHz source up to 10MHz?
Also, would you have recommendations on the transformer part numbers?
(MiniCircuits, MaCom, etc)? I think the transformers are probably key to getting
good phase noise (preventing them from saturating, crosstalk, etc).
Do you have a suggestion on who makes the best (lowest-noise) JFets?
Where could we find the original paper's PDF?
Lastly, how much fundamental attenuation would you expect from such a
circuit?
Thanks!
Said
************************************** See what's free at http://www.aol.com.
More information about the Time-nuts_lists.febo.com
mailing list