I think the difference on the Tek MDO is that the SA port has higher BW than the analog channels (6GHz vs. 1GHz), and it's also real-time so it could trigger on infrequent spectral events. So, it's not the same as running FFT on the regular channels. But I think Paul is implying the functionality was a flop anyway.
Not the functionality so much as the business case - I can't recall a single customer of mine saying "You know, this would be a great scope if only you had a dedicated hardware, real-time spectrum analyzer in it. And I'd be willing to pay X USD for that function" (where X is a non-trivial percentage of the overall scope price)
(Please feel free to chime in if you are, in fact, such a potential customer
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There are plenty of customers who want a VNA with spectrum analyzer capability, or a spec an that can make (scalar) network measurements (combined with an internal or external generator). In fact, I just recorded a video this morning showing how to do this with our FSW spectrum analyzer - should be on our YouTube channel next week.
But I just haven't seen a lot of demand for a "scope plus RTSA" combo. And I think as scope spectrum / FFT performance keeps increasing, there will be even less demand for that combo.
(Of course, it's possible that this is all just misinformation designed to keep our competitors from releasing a scope + RTSA combo before ours is done ....
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