Hello
I need to generate 2-Level FSK signal using real-time I/Q baseband generator (option UN8) with +-40kHz frequency deviation and 9600 smps symbol rate.
So I've created custom FSK modulation with +-40kHz deviation and stored it in the internal file. After that I set symbol rate to 9.6 ksps in Symbol Rate menu.
But when I try to choose new created FSK modulation I've got the Error -221:
User FSK file has deviations which are incompatible with the current symbol rate. The modulation type has been defaulted.
A frequency in the selected user FSK file exceeds the maximum possible deviation for the current symbol rate. The default modulation type for the mode has been selected to resolve the conflict.
But if I set symbol rate >= 40 ksps I can load my FSK modulation preset, but unfortunately I cannot decrease symbol rate less than 40 ksps after that.
So the question are there any limitation of symbol rate to not be less than deviation frequency?
I didn't find any information about it in the documentation.
Thanks for any information.
I'm not familiar with the E4433B but it sounds like the symbol rate is used to set the Arb/FPGA clock rate. You might be able to get what you want by setting the symbol rate to 48 ksps (5 * 9.6 ksps). Then expand your symbol data by a factor of 5. not sure what the symbol data looks like but if it was a,b,a,b then you would expand it to a,a,a,a,a,b,b,b,b,b,a,a,a,a,a,b,b,b,b,b.
Hope this helps
Pete