voltage reading at DAQ board is not same with the voltage input supplied

[syedanas]

hi guys,

i am doing this project.the project is as the figure in the attachment below.

im trying to create a simple GUI which will display the voltage input at analog pin a0 and a1.my question is;

1)why is the voltage input supplied to the DAQ is different when it display at the the front panel compare with the one i measured with a multimeter.the gap in the reading is huge.

2)i am using index array to separate the voltage from a0 and a1 in a single task,is that applicable?

3)if i want to display the reading of the voltage input at different point of frequency range 1-3 Ghz ( sweep frequency),how should i do that.there is already a RF generator connected to the device,so do i need to make a sweep frequency VI also in the labview?

the vi is at the attachment.

[crossrulz]

I don't have LabVIEW available right now, so I can't make any comments related to you code.

1.  What are you reading and what should you be reading?  It is likely something as simple as not wiring up the grounds.

2.  If you have a DAQmx task with multiple channels, the Index Array is the way to get your individual channels from a multi channel read.

[syedanas]

hi crossrulz,

 the first question about the reading, i think i am able to figure it out..many thanks to you..but right now, the voltage reading at a0 and a1 is about the same..seems that, the channel reading is not separated by array from the single task of multiple channel.how should i do with the index array right now?.thank you

best regards,

anas