Hi Based on your data the floor of the taps are a bit lower than I thought. I have only looked at a full system end to end. I was looking at AVAR so the numbers would not compare directly.
Very few people have lab standards that run -120 dbc/Hz at a 1 Hz offset. Even fewer instruments have a floor below that. Looks fine for driving test gear. Not what you might choose for a phase noise standard. Bob On Jul 27, 2011, at 7:10 PM, John Ackermann N8UR <[email protected]> wrote: > I'm not sure if there's been other data posted, but a few years ago I did > phase noise measurements of the 8140T as well as HP 5087A and TADD-1. That > info is at > > http://www.febo.com/pages/amplifier_phase_noise/ > > I got my hands on a tub full of 8140Ts but don't have the 8140 driver. > However, all you really need to drive the taps is 10 MHz at ~10 dBm (not sure > the exact spec) riding on 12VDC. > > I built a power injector to put 12V on a 10 MHz sine wave tapped off the > 10811A output in a 5065A Rb and used that to drive a string of about 10 > 8140Ts in my old lab. I terminated the string with a blocking capacitor and > 50 ohm load; you need the capacitor to keep the DC off the load. > > As has been pointed out, the 8140T isn't the lowest noise distribution system > you can get, but it sure is a convenient way to put a bunch of 10 MHz spigots > around the basement and the performance is adequate for anything but the most > critical applications. > > John _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
