saidj...@aol.com said: > here are some plots from two GPSDOs, one series terminated (CSAC GPSDO), > and one load-terminated (Agilent 58503A) product.
Nice pictures. Thanks. My reading of your pictures is that the 58503A has a weak driver. Do you have a TBolt? > ... and there is a little hump right at the beginning. That could be a reflection from an impedance change. I wonder what's inside the box. > I don't know what the output circuit of the 58503A looks like, but > assuming that it probably is the same as on the Z3801 units many folks here > have it is quite relevant to this discussion, and comparing these two > approaches really shows the quality difference between these two products' > signals. The Z3801 doesn't have a simple BNC connector for the PPS. Their are 2 pairs of differential PECL signals on the DB-25. I haven't looked at them. If all you want to do with the PPS is feed it to NTP, you don't need ns level accuracy. There is a standard recipe for converting the RS-422 levels to RS-232 and borrowing one of the drivers for the PPS signal. RS-232 drivers are deliberately slow enough to avoid most of these problems. The 10 MHz comes out on a BNC. That's what most hams use for multiplying up to GHz. -- These are my opinions. I hate spam. _______________________________________________ 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.