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fm modulation sync pxi-5652

I have a PXI-5652 running in a PXI-1031 chassis.  My data system is in another PXI chassis running RT, I need to sync my DAQ to the 1KHz triangular FM modulation of the PXI-5652.  Can the 5652 output a sync pulse that coincides with the triangular modulation or could porting the system clock of the RT chassis to the 5652 allow me to sync the systems in some way?
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Hello Bruce,

I probably not understanding what level of synchronization you need but what task are you doing with the DAQ card and what model number is it? This will determine if you can reference the two to the same clock source. They will lock in frequency but they will drift over time.
If your modulated signal is so small in frequency (1 kHz), could you not do it with a simple frequency generator or even an M Series DAQ card?
Could you elaborate little more if this information is not totally related to what you were expecting?
Gerardo O.
RF SW Engineering R&D
National Instruments
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Thanks for your input Yardov, I'll try to explain my situation better.  I am running a real-time DAQ system that uses the PXI-5152 digitizer.  I have another PXI chassis that has a PXI-5652 RF signal generator.  I would move the 5652 to the RT chassis, but unfortunantly, the 5652 isn't supported by real-time.  I am using the RF generator to produce a FM signal.  This signal has a carrier frequency of 3GHz, and is being modulated 800MHz by an internally generating triangle wave at a rate of 1KHz.  I need a trigger signal for the DAQ system that is in sync with the 1KHz triangular modulation waveform. 

The only thing I could think of was using the 10MHz system clock of the RF signal generator with a divide-by 1000 circuit but I haven't tried it.  I was hope someone else would have ran into this problem before and found a solution.




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Hello Bruce,

There are two problems I see for this application using 565x:
  1. At the frequency range you are generating, the maximum frequency deviation is about 1MHz. You can find this information in the specifications of your card.
  2. This is a frequency synthesizer, meaning that there is no reference on where the signal is. For this reason, we cannot correlate the DAQ card to the 565x.
However, you can use a 567x and then the ARB will be able to sync much better with your signal. Your phase might be drifted since the upconverter clock is not exposed but you should have better results.
Hope this helps,
Gerardo O.
RF SW Engineering R&D
National Instruments
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