Sec.  15.23   Home-built devices.

   (a)  Equipment  authorization is not required for devices that are not
   marketed, are not constructed from a kit, and are built in quantities of
   five or less for personal use.

   (b) It is recognized that the individual builder of home-built equipment may
   not possess the means to perform the measurements for determining compliance
   with the regulations. In this case, the builder is expected to employ good
   engineering practices to meet the specified technical standards to the
   greatest  extent  practicable.  The  provisions of  Sec. 15.5 apply to this
   equipment.