NOTE  GOODMAN S.248
A     Y.K=DELAY3(X,D)
A     Z.K=DELAY3(Y,D)
C     D=50
R     X.KL=TABLE(XT,TIME.K,0,125,25)
T     XT=0/10/0/-10/0/10
PLOT X=X,Y=Y,Z=Z(-10,10)
SPEC DT=0.5,LENGTH=125,PLTPER=2