So current digital oscilloscopes ever save waveforms direct to USB?

[Ecklar]

The new Rigol DS2000 show memory depth of 14M and optional 56M.  Do any of these current digital scopes ever use a plugged in USB stick as memory depth?   It seems like to easy a solution;  what am I missing?  I'm new to scopes. 

Eck

[H.O]

Hi,
Not sure what you mean exactly.....
On most (all?) modern DSOs you can save screenshots and/or actual waveform data (once captured) to a USB drive.
But if you're talking about having the USB drive as the main acquisition memory (and therefor get a memory depth of 4G for a couple of bucks)  then no, it doesn't work like that.

Your typical DSO captures tens of thousands of waveforms per second, each waveform cosisting of tens of thosands of bytes (depending on scope settings of course). These bytes needs to be continuosly "streamed" to memory (and from memory in order to build the waveform you see on the screen). For this you need fast RAM "tightly" tied in with the ADC's and main processing CPU/FPGA etc. Having FLASH memory on USB won't work.

[Mark_O]

Another way to put it would be to ask the OP,  "What USB memory sticks are you aware of that write at 2 GB/sec?"

A little bit of common sense can go a long way in this field.