Phase and Jitter of ET6000 outputs


Per the documentation,  outputs J4 through J9 are available to drive loads.  Furthermore, if option 40 is added, then J3a through J3f  can also be used to drive external loads.
To serve our needs, the jumpering was changed to pick up a multiplexer output, except  J7 which was left jumpered to 10 MHz sin wave output.
The outputs of the unit have different skew with respect to each other. (Log page 141, 142)

10 MHz Phase Skew for three outputs of an ET6000 GPS clock
J3e, J3f and J7 10 MHz Sin outputs;  (trigger J4)  Average 16 seconds 
J3e, J3f and J7 10 MHz Sin outputs;   (trigger J4)  20 seconds,   ∞ persistance
10 MHz output phases
 Clock phase jitter
The channel assignment is the same as in the image to the left.
I read this as about 1ns jitter with respect to the channel 4 triggering reference.


Oscilloscope Channel Input Skew Verificaton
Ch1, Ch2, Ch3: matched 10 ns Cables // Ch4: ~5ns
Ch1 to Ch3 match
 Ch2  to Ch3 match
Ch2 to Ch3 phase match
Ch4 is a common trigger signal selected for convenience
 Ch2 to Ch3 timing
Ch4 is a common trigger signal selected for convenience
From the above screen-snaps, it is obvious that the the cable and input, together, for both Ch 1 and Ch2 are very closely matched.  This condition is needed for the comparisons that follow:
One Pulse Per Second Channel to Channel Skew
J8 to J9 1 Hz timingJ8 to J9 delay
  Condition:  Jitter during several seconds of acquisition ???
J6 to J9 1Hz SkewJ6 to J9 delay
J5 to J9 1Hz skewJ5 to J9 delay
J4 to J9 1Hz SkewJ4 to J9 delay
J7 to J9 10 MHz to 1Hz skewJ7 to J9 delay







Channel skew for relative timing measurements of pulse output skew
Ch1 to Ch2 measurement skew