I got the RTB2004-COM4 promo, so why not wait for the MXO4-COM4 package....
I am still trying to figure out the FFT architecture. From this video:
https://youtu.be/acE3d4TpiW4?t=46
it looks like changing the FFT settings also changes the time domain acquisition settings. Reducing the RBW 500Hz -> 400Hz -> 300Hz also reduces the sample rate from 1000 -> 833 -> 417 MS/s, which is what I would expect if the FFT were dependent on acquisition data (lower RBW => longer FFT window => longer acquisition) but not what I would expect from an independent FFT pathway.
The ability to have an independent FFT acquisition path would be very helpful for applications that require a low time-domain sample rate but a high RF sample rate, e.g. looking at a low frequency power rail, spi bus, or VCO control at the same time as a corresponding 900MHz RF burst. On my bench, this is a very common situation. If the FFT must be calculated off acquisition data, the high fundamental frequency of the RF burst demands a high sample rate even though "morally" it has a lower information requirement driven by RBW+span. If the FFT and time domain have separate acquisition paths, these requirements are not in conflict, because the FPGA can send an efficient lowpassed time-domain trace alongside an efficient spectrogram, rather than a big inefficient block of full-rate samples suitable for calculating both of them. To the user, memory efficiency is visible as the maximum acquisition time when RF+DC pathways are active. If they are dependent, max acquisition time is milliseconds, but if they are independent, it can be many seconds.
I want to believe that the MXO resolves this conflict with independent measurement pathways, but the video makes it look like the MXO has independent FFT in the more limited sense as the older R&S scopes, where you can trade off RBW against the number of stacked/overlapped FFTs, but you cannot have low-sample-rate time domain signals at the same time as high-sample-rate FFTs. Could you clarify which definition of "independent" is in play here? Thanks. (EDIT: I made & pulled this same post yesterday, not wanting to cause out-of-hours work, but I was too slow and got an answer by PM anyway. Apologies.)
The 18 short (~1 minute) videos showing different features of the MXO4 are now live on the Rohde and Schwarz YouTube channel
https://www.youtube.com/user/RohdeundSchwarz/videos
I hate the shiny screen though, so...
Buy a tablet matte screen protector. Then cut it.
Not a 12 bit scope, but I took the same measurements on my 8 bit RTO with 20MHz and 200MHz HD filters:
https://www.dropbox.com/sh/e00tn9mtlpsd6gx/AABKMUdwkqgnRjF2VQDP6k_Oa?dl=0
(all traces are 10GS/s with filters to reduce bandwidth and improve vertical resolution)
Back-of-the-envelope says it starts at ENOB 7, the filters chop noise bandwidth by 20x, so ideally another ~2 bits and ENOB around 9, which is where most 12 bit scopes seem to land anyway. I'd love to see the apples-to-apples comparison of what it actually achieves, though -- I suspect the ENOB figures on the 12 bit scopes might be suffering from some kind of worst case and that the 3 least significant bits aren't typically complete rubbish.
Not a 12 bit scope, but I took the same measurements on my 8 bit RTO with 20MHz and 200MHz HD filters:
https://www.dropbox.com/sh/e00tn9mtlpsd6gx/AABKMUdwkqgnRjF2VQDP6k_Oa?dl=0
(all traces are 10GS/s with filters to reduce bandwidth and improve vertical resolution)
Back-of-the-envelope says it starts at ENOB 7, the filters chop noise bandwidth by 20x, so ideally another ~2 bits and ENOB around 9, which is where most 12 bit scopes seem to land anyway. I'd love to see the apples-to-apples comparison of what it actually achieves, though -- I suspect the ENOB figures on the 12 bit scopes might be suffering from some kind of worst case and that the 3 least significant bits aren't typically complete rubbish.
Jjonathan could you post a picture of yours R&S RTO1044 in HQ. In my opinon the RTE, RTO scopes looks much more professjonal and well doned
But one thing is interesting, you can upgrade the bandwith from 200Mhz up to the topmodel 1.5Ghz, so it´s always the same hardware.
Nice thing for hackers..
And interesting the second, buying the upgrade from 200Mhz to 1.5Ghz is NOT more expensive than buying directly the 1.5Ghz model.
Same here, around 10k makes it nearly (but not completely) impossible to buy in private.
But I would love to see "more" from it, it´s a very sexy scope from the first view..
Are there any review videos coming up on the MXO4 ? Seems to me to be too quiet around that device - even if I cannot afford it, it would be interesting.
I've been busy with other videos and scopes, and there was this
It's being swapped tomorrow.
https://odysee.com/@eevblog:7/MXO4-Screw-Loose:2