If I look at the DSO, it seems an approach where they can do the digital design (RAM, LCD controller, FPGA) but didn't spent any effort on the analog side of things. YEs the split ground plane, but I also learnt that the ground plane should be joined at the ADC in most cases. So go figure
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And then they do have a working digital side, and put CRAP firmware on it. I mean, the Rigol 1052 has a 320x240 screen, and it can put 2 waveforms on it decently with good menu's.
The analog bandwidth ofcourse is complete bullshit. 200MS/s is 20MHz at most. But without a sin(x)/x interpolation, it doesn't look pretty at all.
The micro seems like only handling buttons. If you follow the board you see it moving straight across to the button side and just reading the damn inputs. Seems like they were short on I/O or something. Shift registers?
The A/D seems legit in that it's actually a
dual 100MSPS ADC. Well, if it's not counterfeit. Mike pointed out the laser markings were not aligned straight...
Seems the input is pretty simple. Voltage follower (with diode clamps on the input, look at the size of those - how long would the survive an overload?), crappy voltage gain (with selector feedback resistor, great!) and into the A/D. Great, maybe they should buy a VGA/PGA next time.