davidwh...@gmail.com said: > Doesn't the Rigol have delayed sweep or is it zoom only?
It has a delayed sweep. You can delay long enough so that the trigger event is not in the buffer. After you capture a buffer, you can zoom and pan around in it. If the sweep is 20 ms/div or faster, the screen shows 1/3 to 1/4 of the buffer so you can zoom out slightly (after you stop it). If the sweep is 50 ms/div or slower, the screen shows the whole buffer. It's actually a bit more complicated than that. If the sweep speed is too fast, the buffer bandwidth is the limit so the screen shows a much smaller portion of the window. There are 2 buffers: 16K and 1M. (You can pick either one.) If you are using both channels, they each get half of the buffer and half of the buffer bandwidth. The 16K buffer writes at 1G samples/sec. The big buffer is half that speed. > Do any GPSDOs come with a low > jitter 1 PPS output? TBolt and HP Z3801A both have PPS outputs. I assume they are derived from the OSC rather than directly from the GPS receiver so I expect they are low jitter. Aside from reducing jitter, you have to do something like that if the PPS is going to be useful during holdover. I'm looking at the PPS outputs from 2 TBolts, triggering on one. I've got the scope in persist mode. There is about 2 ns of smear on the signal it's triggering on, only 1 ns if I turn off the other channel. I think that's just from the sampling quirks. The other channel has smeared over 20 ns. That's after letting it collect for 20 minutes. There is a lot of low frequency wander rather than simple jitter. It will probably wander father if I wait longer. -- These are my opinions, not necessarily my employer's. 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.