Hi Thomas, About the 53230A -- like many of us I figured there was no point in buying the expensive OCXO versions since I have plenty of good 10 MHz references around here. So years ago Keysight loaned me two of them for a month: one with, and one without OCXO. Like most counters, the 53230A has an ext-ref input. But it is horrible. And the ref output is even worse. I think we've discussed this on the list before, including ADEV and PN plots. I decided not to buy one, ever, until they fixed the problem.
So it could be a nice counter. Someone at Agilent / Keysight needs to re-design the int/ext/mux/pll clock handling of the 53230A; someone who understands phase noise and short-term stability; someone who honors the intent of ext-ref-in and ref-out; someone who keeps stupid microprocessor / LCD / comms / power supply noise out of the clock path. Meanwhile I keep my old 53132A's and older SR620's and stay away from the 53230A. If you have your own measurements, please share. Maybe I just got a bad sample, I don't know. But the ext-ref performance smelled like poor engineering to me. My hope is that someone on the list will hack a 53230A, fix the problem, and share the solution with us, or even with Keysight. /tvb > Hi All; > > How important is the standard, medium, or high stability reference in > counters like the 53230A, or FCA3120 when locked to an ultra low phase noise > external reference? Particularly when making measurements and adjustments on > other ultra high performance references? > > I know Agilent sold 53132A counters with an option (H01 I believe) that > bypassed the internal reference completely when and external reference is > applied, but I think standard configuration on most counter is to discipline > the internal reference. > > Thanks for your thoughts. > > Thomas Knox _______________________________________________ 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.
