- From: Calin A. Culianu <calin_at_ajvar.org>
- Date: Wed, 13 Nov 2002 13:51:15 -0500 (EST)
I was just reviewing your email which recommends the 6071E from NI. At any rate, I was wondering how you are doing signal conditioning for 64 channels? It seems that all the SCXI stuff NI offers likes to multiplex multiple inputs from multiple SCXI modules onto one physical AI channel that goes out to your DAQ device. This means you have to de-multiplex all 64 channels in software. How are you overcoming this problem? Are you doing your own homegrown signal conditioning? Or are you using SCXI and de-multiplexing in software? Thanks for any help offered.. -Calin On Wed, 2 Oct 2002, Tim Holy wrote: > Hi Calin, > > I use a NI PCI-6071E board to do 64 channel acquisition, 10kHz per channel, to > record spike waveforms from neurons. (It's only 12-bit, so it may not be the > board for you.) While the board specs say it can do 1.25MS/s, implying that > we could do almost 20kHz/channel, the errors due to finite settling-time > increase when we go that fast. NI is very straightforward about this point in > their specs and (with the tiny bit of checking I've done) seem to be accurate > in their measurement of the errors as a function of scan rate. I certainly > wouldn't shy away from paying the extra $500 if it turns out to be the better > board (I don't know if it is, since I haven't tried any MC boards). Compare > it to the lost labor [& pigs :-)] for corrupt data. > > Your signals are well-buffered, right? I've occasionally seen weird things > with the multiplexer putting junk back on the channel when using e.g. just a > transistor to buffer signals. >
Received on 2002-11-13Z18:51:15