ISTR reading somewhere that it was felt that the target markegt (beginners) would complain if they felt they has been mislead by finding the amplitude of a 5MHz signal was too low. Personally I don't agree with that, since they will need to understand what equipment's spec does and doesn't mean.
That is correct. On page 16 of the
technical manual it show plots of the frequency response and states:
"You can see from the plots, that this circuit exceeded the requirements for 5MHz of bandwidth, and the -3dB
point is more than 20MHz. However, since many students who will be using the Analog Discovery don’t
understand the concept of “-3dB” is the “bandwidth” of an instrument, and that a 1V input signal with -3dB
applied will measure 0.707V, it was felt from a marketing standpoint to specify the bandwidth of the analog
inputs as less than -0.5dB as the “bandwidth”. This ensures that when connecting a 10MHz signal on a
traditional instrument (with much higher bandwidth), and the Analog Discovery, the measurements will be
very similar, and lead to less confusion."
I agree with you that students should learn what instrument specifications really mean.
On the other hand, the reality is that without the opotional BNC adapter board and a x10 oscilloscope probe, the usable bandwidth will be below the actual -3dB point.