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RFSG Long AM Modulated Sweep

I need to create an RF signal using the PXI-5610 & 5421 with the following characteristics:
1. Carrier frequency = 300 MHz
2. One second wide pulse
3. AM modulated at 90% mod depth with the following signal
   a. At time t=0 sec, 6300 Hz
   b. At time t=1 sec, 6700 Hz
   c. Linear sweep between 0 to 1 sec, i.e. at 0.5 sec the instantaneous frequency should be 6500 Hz.
 
I have tried numerous combinations of blocks to no avail. It seems that I would need to define an arbitrary waveform of 100MSamples in order to cover the 1 second pulse, which of course I don't want to do. If I try to define a manageable waveform of say 100KSamples, it works but the sweep is only over 1msec and the repeats 1000 times over the one second - obviously not what I want.
 
Any help would be appreciated!
 
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Hello LostAtC,
The PXI-5670 RF Vector Signal Generator produces an IF output signal from the PXI-5421 between 15-35 MHz, centered at 25 MHz. In order to cover this bandwidth, the PXI-5421 always outputs at a sample rate of 100 MSamples/sec, since the next lowest sample rate possible would be 50 MS/sec, which would have too low of a Nyquist BW.
The main point here is that when sampling at 100 MS/sec, a 1 sec waveform will take 100M samples unless parts of the waveform can be repeated via scripting in NI-RFSG.

One option would be to create the waveform offline and store it in a file, which you could then read directly from and write to arb memory.

If this is unacceptable, the PXI-5671 contains Onboard Signal Processing in the form of a Digital Upconverter (DUC) which can alleviate this. Contact your local Sales rep and they can explain the benefits of the PXI-56761 to you.

Regards,
Andy Hinde
National Instruments
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