Abstract: A plurality of fragments of printed circuit boards, so-called coupons, each having a row of plated-through holes to be examined and two reference holes, are mounted on positioning pins extending through the reference holes, and are then embedded in a molded block of a curable plastic material to form an independent multi-coupon sample with extending pin ends. A plurality of such samples are mounted in pockets of a sample holder so that their extending pin ends engage with hardened surface portions on the front face of the sample holder. The samples are then contacted by an abrasive element to remove material down to a cross-sectional level at a predetermined distance in front of the hardened surface portions. A jig can be used to cut out a coupon with reference holes from a circuit board.

Abstract: A plurality of fragments of printed circuit boards, so-called coupons, each having a row of plated-through holes to be examined and two reference holes, are mounted on positioning pins extending through the reference holes, and are then embedded in a molded block of a curable plastic material to form an independent multi-coupon sample with extending pins ends. A plurality of such samples are mounted in pockets of a sample holder so that their extending pin ends engage with hardened surface portions on the front face of the sample holder. The samples are then contacted by an abrasive element to remove material down to a cross-sectional level corresponding to the common diametrical plane of the plated-through holes. A jig can be used to cut out a coupon with reference holes from a circuit board.