Peter, it will be difficult to degrade -138dBc/10kHz using a ADF 4001. I have PLL's using selected $ 1.00 Xtals getting better than -153dBc/10kHz. .Axtal has units with -174dBC but out of most price ranges but I thought you were looking at below -150,very doable with ADF 4001. Bert In a message dated 9/19/2011 5:53:22 P.M. Eastern Daylight Time, krengelda...@gmx.de writes:
Thank you all for your suggestions. @ Attila: I think your suggestion would be "a little bit" too complicated. I dont want to write a dissertation :)) My idea was to simply get a low jitter out of the 100MHz TCXO clocking the FPGA etc.. The fine TCXO I like to use is a AXLE20-12 from AXTAL. I think its expensive enough for my experiments (about 100,- EUR) and it also got a electronic frequency control input as well as a even much more expensive OCXO which would cost me 180,- EUR or more. As I said as the ADCs are working in cascade they have to be enabled and disabled as exact as possible to avoid sampling errors. A jittering clock would do a bad job in that circuit while long time stability is not a problem. @ Chuck: A good idea in principle but I only have one tbold which controlles all my measurement equipment like spectrum analyzer, signal generators a.s.o. I also dont know whether a synchronisation of the 100MHz TCXO to the tbold will really give me a better noise figure than running the TCXO stand alone. The TCXO I like to use gives me a low noise of -138dBc/10kHz and as far as I know tbold comes with -142 or even better. So the main question is whether a synchronisation will give better results or not. If so an additional effect would be the fact that all equipment is then working synchronous. The ADCs I use will get a part of a homemade 1GHz DSO. @ Bert: Thank you for the hint. I think to use a ADF4001 is an easy task so I like to start my experience first using your idea. Again thank you for even more suggestions. Regards Peter, DG4EK _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.