How to run continuously the "Downconverter with External Digitizer vi " ?

[Yamoussa]

Hi,

I'm using PXIe-5663 on PXIe-1075 chassis. I aim to use "Downconverter with External Digitizer .vi" in order to run the Downconverter PXIe-6901 continuously. To do this, I added a while loop to the sample provided (see attached file). The problem is that the while loop doesn't make any changes; the program stops as soon as its launching.
Is there anybody who can help me with this problem please ?

[KittF · Accepted solution]

Yamoussa,

The 5663 consists of 3 modules: 5622 digitizer, 5601 downconverter, 565x local oscillator.  

The example you reference is typically when you decide not to use the include 5622 digitizer, but still want to use the other 2 modules in order to send in the downconverted IF signal into a different digitzer. 

Can you confirm this is what you are trying to do before we move forward in trying to address your questions?

[shawn.t · Accepted solution]

Hi,

The purpose of the "Get Frequency Response" VI is to aid in correcting the response of the downconverter in your acquired data. The response of the downconverter only changes with frequency and reference level. In your VI, you're looping on the "Get Frequency Response" call but not changing the frequency or reference level so the output of the VI will not change.

To use the external digitizer, you want to set center frequency and reference level in RFSA, read the frequency response and downconverter gain in RFSA, acquire data from the external digitizer, and correct it using the downconverter's frequency response and gain. You can loop on the acquisition and processing portions until you need to change center frequency or reference level.

[Yamoussa]

Hi shawn.t,

Yes, this is exactly the purpose.

[Yamoussa]

Hi shawn.t,

Yes, this is exactly what I meant to say.

[Yamoussa]

Hi shawn.t,

Thank you so much for your quick answer. It's been very helpful for me.