[time-nuts] Need 10 MHz for DSN space-probe hunting
Charles Steinmetz
csteinmetz at yandex.com
Wed Sep 14 16:01:09 UTC 2016
> Just wanted to add, their US distributor has one with a custom xtal that claims even lower phase noise and has provided a plot comparing the two
I see the US distributor says the "custom" unit's phase noise
"improv[es] on an already impressive figure" of the stock unit. But in
reality, even the custom unit doesn't have an "impressive" PN figure --
the phase noise is still at least 10dB worse than a real GPSDO. It
appears that the outputs are generated by a DDS or similar, so that is
not surprising. Good for frequency agility, lousy for frequency
stability and spurious outputs.
This thing has its place in the world of clocks, but it is *not* a
precision GPSDO. It is not even in the league of a number of hobbyist
and DIY designs. I wish people would stop recommending it to people
whose application calls for a real GPSDO (such as multiplying up to the
GHz region).
Best regards,
Charles
More information about the Time-nuts_lists.febo.com
mailing list