Lisp help - lts before plot

[M_c3d]

I'm trying to write a lisp to set the lts to 1 before plotting;

(command "_.undefine" "Plot")
(defun C:Plot () (ltscale;1;) (command "_.Plot"))

It does the lts part properly, but it says unknown command "PLOT"

Any ideas what I'm doing wrong? or if this is at all possible?

Thanks,

[ВeekeeCZ]

Maybe like this? Not sure whether you want to have a dialog or not... 

(command "_.undefine" "Plot")

(defun C:Plot ()
  (setvar 'ltscale 1)
  (initdia) ; dialog?
  (command ".Plot")
  (princ)
)