Analog Output through SH37F-SH37M cable has high-pass characteristic (~2kHz corner)

[wasmith2]

I'm not sure if this is a bad cable or if it's AC coupled or if I'm just setting something up incorrectly.  I can't really tell from the documentation.

I've hooked up a SH37F-SH37M cable that came with my NI9264 analog output module.  Channels have a really stark high pass response and the corner appears to be on the order of a couple of kHz, although I haven't yet gone to the trouble to properly characterize it.

I'm directly driving an oscilloscope with 10MOhm input impedance.  It seems really unlikely that this is inductance, given the frequency of the corner.  Do these cables have some sort of series capacitance?

When I use the module directly without the cable (by interfacing directly with the DSUB output pins on the NI9264) I do not see this issue, so it's definitely something to do with the cable.

[IronBrotha]

Hello  wasmith2

These cables do not react as a capacitance as far as I know.

This is a really odd behavior. Have you tried with another cable?

[crossrulz]

This sounds like you have a break in the wire or a bad solder joint causing some capacitance.  I would recommend finding a new cable.

[wasmith2]

I figured as much, but we only have the one cable that was delivered with the NI-DAQ.  I'll order another cable and see what happens.

[crossrulz]

Before you go an order another one, talk with your local NI representative.  They may be able to get you a new one to try and then trade in your suspect cable.