Will the SDS2000X Plus utilize the full BW of the external SDG6000X AWG in Bode Plot mode?
I know this works with the SDS2102X Plus "enhanced" to 350MHz with SDG2042X which has been "enhanced" to 120MHz, this allows a full 120MHz Bode Plot sweep 
Added plots showing a RG58 cables (3) & Banana to BNC adapter test using the Bode Plot, note the null caused by the high impedance reflected scope impedance (1M) and RG58 cable on C1, C2 was terminated (internal) with 50 ohms. Second Bode plot shows a standard cheap BNC "T" adapter with 3 RG316 20" cables with a high impedance (1M) scope input on C1 (C2 50 ohms), also note the null caused by the high scope impedance. Third is a plot of 3 RG316 cables (AWG, C1, C2) with both scopes inputs C1 and C2 terminated, so not a proper "matched" connection at the "T" but yields much better performance (proper "T" match would have been a 3 way 50 ohm power splitter). I often use this type improper "T" connection rather than an open circuit or high impedance when working beyond 10MHz with 50 ohm cables.
These Bode plots clearly show why you shouldn't use Banana adapters or standard 50 ohm cables beyond about 10MHz with a high impedance loads, the reflected high/open circuit causes a very low impedance at 1/4 cable wavelength which causes significant attenuation at these 1/4 wave frequencies.
The Bode Plot can be useful in everyday measurements and an added benefit of these popular versatile DSOs.
Best,
BodePlot limit is max 120MHz as far as I know. It is limited by AWG in use or 120MHz depending which one is lower. Also 120MHz is bit too high but usable for some simple things if do not need high accuracy, specially phase is problem. Also Signal generators start reduce output level with higher frequencies so it also start limit usable dynamic range when testing passive circuits. Of course case with active circuits what may have amplification etc then dynamic range max is what is BP itself dynamic range.
Something like this (This is OLD (and possible obsolete after FW updates), just for look it in freq range where are mostly HF radio receivers filters etc.)
As can see there is SDG1000X up to 60MHz band dynamic range ( based to my some tests) what is roughly up to 100dB. Best range is where are most HF receivers IF filters. But of course scope can handle much higher amplitudes so if DUT is amplifier dynamic range can be higher. But then need also "bit different" grade feed thru terminator depending what is max power. 60dBm (1kW) max it can be up to 160dB single sweep dynamic range and this is lot but you need 1kW 50ohm feed thru. So... perhaps not for "everyone".
Siglent BodePlot performace and features are handled some amount in specified thread in forum. It is there handled using SDS1104/SDS1204X-E what is, afaik, quite same what is on SDS2000X-E and 2000XPlus models.
BodePlot support all Siglent AWG X models.
If need work over roughly said 20-40MHz it is not enough to use just good cables and of course impedance matching is nothing more but mandatory. But even it is not enough. For good tests with higher frequencies need do time calibration and it is not so simple. Oh well it is simple if user have some special things... what most of users do not have.
But if start talking bit more deep things then need write one book.
What is ok for low freq very simple things just all these can throw away if do something other than just play fun things.
Example some things may need double channel setup where input to DUT is separated from input to BodePlot Reference but it need know how to calibrate this setup for some measurements. Example if use dual channel generator setup how to do timing calibration (for get real phase instead of "something"). There is skew in generator, cables propagation times need match and scope channels skew... these timing things need calibrate just for individual setup and settings.
One degree in phase is roughly 28ps when freq is 100MHz. Example with RG58 (PE type, example Belden 9201) roughly 5.5mm length respond 1 degree phase shift (velocity factor is 0.66). And after then come scope inputs internal skew what need compensate externally! If need even somehow accurate phase all these need zero, one possible tool is adjustable length coaxial. Then also impedance need match and it IS difficult part due to facts about signal generator output and scope input circuits.
All is simple with audio frequencies.
And then if go over 50MHz...over 100MHz things goes much more difficult. So my opinion is: 120MHz limit is good and even it is bit high. Perhaps 60MHz is better limit.
Of course "something" can do with 100MHz and even with bit higher but then we go more up... results goes more to "entertainment" grade than test and measurement instrument grade and I do not like if test instruments include these "game boy features" for play just some fun.
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But. Topic is Rigol - Siglent.
I wonder bit why there is nearly total lack of information and truth about Rigol BodePlot function in MSO5000 model.
In my previous message there is many questions about RIGOL - without any single answer. And answer can not find from Rigol and not here.
(same as with GoodWill BP and same as with Keysight BP in they low end models, just nearly nothing)
Resolution, Span, swept measurement dynamic range etc etc and if they are working using swept frequency selective receiver or just simplest broad band scope channel.
Please even freq resolution... just someone who have this scope. Open BP and set and look and tell numbers.
Set 1MHz center. What is minimum span. What is minimum freq step.
Set 1MHz center and span 1kHz. What is minimum freq step. If minimum span is smaller, then do it give more freq resolution.
Of course if someone can tell more it is nice. If also can know maximum usable single sweep dynamic range. And whole freq range dynamic range if test signal to DUT is just 0dBm what is then max usable dynamic range (yes this need bit work for test). And how many channels simultaneously max from DUT. Manual tell that user can select channels 1 - 4. Do it have 4 channel BodePlot or just select what single channel is in use for BP.
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