Bought PCI-6251 from lab liquidation, chip on pcb missing or stripped version modell?

[antyama]

Hi,

I've aquired a used NI PCI-6251 DAQ from a Lab liquidation and I can't get it to work, an I'm not sure if its because there is something missing on the PCB or if I'm doing something wrong regardless. I'm trying to get it to work via a PCI-Express X1 to PCI bridge adapter, which might be the cause but I'm not sure.

Model is PCI-6251 (190996F-03L)

I've also attached a picture of the "missing" place, I gathered online that there should be a ferrite bead / inducter bead there I think, my question is basically, is that just an offshoot version or am I actually missing a component on here?

[santo_13]

It must be an inductor, "L8," and was also damaged and stripped off the PCB trace.

Good thing is you are good with soldering, you may be able to wire the trace to the end points and glue in an equivalent inductor but this raises the question, "what else is damaged?"

[AnalogKid2DigitalMan]

Images on the web show cards with and without L8 present. Probably different design revisions throughout the years.

I suspect your adapter may be an issue.

EDIT: I may be wrong about L8, just realized the image I was looking at was actually a 6250 (which was also missing additional components found on the 6251).

I would still try to find a PC you can plug it into directly, if possible to eliminate the adapter as a potential issue.

-AK2DM

[rolfk]

You received sound advice. That L8 looks slightly suspicious, but it may simply be a variant for certain markets. Some markets require higher noise suppression and other similar requirements and NI might have created different variants or revisions. Inductors are a fairly pricy part so being able to spare one out for every board when you produce several 10000 of them, is definitely a cost factor.

Your use of a PCI extension bridge is in my experience the most likely cause for the card not working though. PCI is a very complex bus, and the NI integrated chips make use of some advanced PCI bus features. Those PCI extenders however are notoriously limited, they almost never support all PCI bus features 100% correct, and NI cards not working with many of them is not a very surprising thing. Sometimes upgrading the firmware of the PCI extender card can help to make it support more PCI bus protocol elements correctly, but quite a few of those extenders are from rather obscure OEM sources. Some engineering company in Farfarawaystan engineered them, then some Chinese or Korean company manufactured them, with no detailed knowledge of the internals of such a card, and then they are sold through all kinds of OEM channels. The OEM seller has little or no knowledge about the actual hardware, but some poor engineer had to put together a driver package that was distilled from a bunch of obscure files that had been mysteriously handed to the OEM as board support package, and after a short while the product gets discontinued from many of the OEMs because there are simply to much trouble with it, and the original designer, if it is even known, has in the meantime already developed a dozen other products and has no interest to go back to relearn what they had designed back then.

So trying it in a real PC with internal PCI bus is definitely the first step to do, to find out if the card itself is damaged or if it is simply the PCI extender not quite living up to its promises.