As one would expect, using 400 lbs instead of 160,000 lbs makes a tremendous difference. (I had set the 400 lbs for DLF and 400 lbs for Force Set multiply)

John in tech support suggested using a .txt file to input the impulse data (from previous post). Does using the DLF generator creates a spectrum that is different from just the normal impulse wave form? If so, is it more or less conservative?

Anyway, I tried this text file approach and keep coming up with an error. The name of the file is "15fps10gal.txt"

*** ERROR *** Spectrum name or type incorrect

What is the correct format for importing a text file into a time history analysis?

Thanks!