Just watched the review - impressive job by Lasmux.Loading and performance are outstanding for the price.
We think the probe might make a good accessory for the GigaWave. We've contacted Lasmux about this - there should be some way to benefit everybody (including users/customers).
One small thing, if you do work something out, it would be nice if the probe would interface directly with the scope without the need for adapters.
Would be nice if it were all powered off the PC but not at the expense of higher noise. SJL had stated that the reason for using USB3 was for the higher currents but I thought they had a lot of margin. Maybe there is enough left to power 4 additional probes at 250mA.
During the review, you can how I am saving the waveforms and recalling them for a reference. Something I commonly do when using a scope. Note the number of steps required. You have to manually select a file name, manually reload them, then manually set the gain and offset. I like the idea of having a memory rather than a file and having the software automatically show the data, properly scaled like my other scopes. The less buttons I need to press and typing I need to do, the better. Something you may want to consider with future releases.
GigaWave with Tektronix S-52 tunnel diode head (<25ps Tr)
https://www.sjl-instruments.com/
Nice, what I would like to see the real time behavior, as 20..80% or 10..90% rise time changes over time
On a LeCroy easy to graph over time as rise f(t).Thanks for the suggestionWe'll add the ability to graph any measurement vs. time to the software. (Fastest update rate would be 1 datapoint per sweep.)
Using your latest release, I can not figure out how. If it is a MATH function, the manual does not explain how to use it. Looking in the Extended Measurement Information, I don't see any options to graph the data.
A few other comments, bugs? If I select a custom scale, say 25mV/div. Then I save that waveform as a reference. When the new reference is displayed, us uses 20mV/div rather than the expected 25mV, requiring me to select Custom, then enter in the 25mV/div. I thought these two would always track but it appears not. Is there a reason why you made it work this way? Personally, I would rather it always work the same way and IMO, less keystrokes is always better.
If I select Color Grading for a waveform with vectors disabled, then save the waveform as a reference, the new waveform is shown with vectors disabled but the color grading is deselected. Is there a reason it does not match?
Have you ever considered adding a way to auto align the data? So, for example, we want to plot the risetime. Now, if the hardware drifts, the transition may move off the screen. For a long term trend, have you considered having the softeware adjust the position automatically (as a option) to keep the transition centered?
It may be nice to be able to adjust (drag) the reference independent from the other channels. For example, if I collect data from channel 2, then change the setup to collect on channel 3 as shown. I want to manually align the two edges.
The reason I brought up the tracking is when looking at these fast transitions, I know that vintage Tektronix pulser will drift a fair amount. Because the pulser's cycle time is so slow, sweep times can easily be several minutes. Using the setting I selected back when I posted the risetime, it requires about 3 minutes to collect a single sweep.
I assume the original question was looking for more than a couple of sweeps, and running a long term test (guessing maybe a day or so) is currently not possible with what I have on-hand without the aid of some sort of auto tracking. That or I need to try and maybe temperature stabilize it.
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Showing two sweeps after an 8hr warmup. Drifts about 25ps (added delay).
It may be nice to be able to adjust (drag) the reference independent from the other channels. For example, if I collect data from channel 2, then change the setup to collect on channel 3 as shown. I want to manually align the two edges.On a reference waveform, you can open the channel settings and enter a timebase shift to adjust the horizontal position.
On a "physical" channel, this setting only relabels the timebase (due to hardware limitations). The behavior for a reference waveform differs in order to allow exactly the application you're describing.
Users have to try and balance the drift and resolution to get accurate data. Here shown with 128pts/div. 20ish minutes for the sweep. We know that time has drifted a lot during the measurement and appears to have added a few ps of error. Still, we are below that typical number and we are certainly pushing your scope's limits.
While it certainly allows me to adjust it. I have to select the advanced tab and type in a number. Personally I would like the option to be able to select and drag the reference waveform with the mouse rather than having to resort to typing on the keyboard.
Got it. We can assign middle click + drag to this functionality. Currently, dragging horizontally with either the left or the middle mouse button do the same thing.
Figuring out if the user is trying to interact with a specific waveform based on mouse position is error-prone (especially in point mode).
It appears that when selecting the "Automatically determine from holdoff" the software does not immediately calculate the new values. Rather is seems to require some event such as changing the trigger level or the holdoff time. Maybe this is by design but personally, I would rather it calculate the new values based on the current settings instead of having to change values to get it update.
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Also, if I load settings that do not have the CDF settings set to auto, they will take effect immediately. If I then load settings that use auto for the CDF, the software does not appear to update to the correct values. Lots of clues.
I tried to save a reference for each sweep. Doing so, I notice the maximum allowed is letter X. More than enough. What is interesting is if you select save reference again, it doesn't round robin. Rather it saves to Y but it turns off the readable scales. Selecting save again appears to have no effect. The only way I found to enable the scales is to turn off reference Y. Personally, I would rather it cycle through the references and never disable the scales. Once X is reached, it starts over writing into location A.
It would also be nice to know when looking at reference A-X, which channels they were derived from. Maybe you could use A1 for channel one for example. Or maybe just add a new indicator.
I don't know if you have had any feedback on how you allow changing of the scale for example by scrolling the center button. I like the concept but it doesn't seem to always work. Sometimes I have the mouse positioned on the scale box and rotating the button will cause the software to scroll through the waveforms rather than changing the scale selection. Even if I left click and the software highlights the scale text, the center button will instead scroll though the waveforms. Other times, I am trying to scroll through the waveforms and the mouse rests on one of the scales and it decides to update the scale. I like the concept but it just needs a little work IMO.
Still does not appear correct when loading the setup with CDF set manual vs auto. Odd is if I expected it to be in auto after loading the setup, I select the CDF sampling options and it changed to auto and starts sweeping very slowly. If I select apply (auto is still selected) it appears to change back to manual. Really odd.