Patent ID: 7518384

Claim:
A method for probing an access point on a printed circuit assembly, wherein the access point includes (i) a via having an electrically conductive perimeter in the shape of an annulus, and (ii) a test probe access structure which includes first and second bead probes formed on first and second positions on the electrically conductive perimeter, the bead probes being formed of electrically conductive solder, and being formed such that either (a) both of the first and second bead probes project in a dimension substantially perpendicular to the printed circuit assembly, or (b) one of the first and second bead probes project in a dimension substantially perpendicular to the printed circuit assembly and the other of the first and second bead probes is incorrectly formed so as to make the other of the first and second bead probes ineffective to project in a direction substantially perpendicular to the printed circuit assembly; the method comprising: aligning a fixture probe with the access point; engaging the fixture probe with the access point, wherein either (a) the engaging causes the fixture probe to make physical contact with both of the projecting first and second bead probes, or (b) the engaging causes the fixture probe to make physical contact with the one of the first and second bead probes which projects in a direction substantially perpendicular to the printed circuit assembly, but not with the other of the first and second bead probes; and exerting compressive contact between the fixture probe and the access point, so as to deform (a) both of the first and second bead probes which project in a direction substantially perpendicular to the printed circuit assembly, or (ii) the engaged one of the first and second bead probes, in the case where the other one of the first and second bead probes is incorrectly formed; whereby the deforming facilitates electrical contact between the fixture probe and the test probe access structure.