To perform a functional component test (FCT) and an in-circuit test (ICT) in the same fixture, use a longer stroke probe for the functional part of your test. QA Technology’s 0.400 [10.16] long stroke probes are designed for this purpose. For dual-level testing, they are easily mixed with their standard stroke 0.250 [6.35] counterparts, available in a variety of sizes. This allows for the same set height when mounting sockets or termination pins for the same serie*.

Long stroke probes are 0.150 [3.81] longer than their neighboring standard stroke probes when the fixture is in the unactuated position. During an in-circuit test, the long stroke probes will be actuated to 0.317 [8.05], and the standard stroke probes will be actuated to 0.167 [4.24], the recommended working stroke position. In the functional test position, the long stroke probes are actuated to approximately 0.060 [1.52], leaving 0.090 [2.29] clearance to the standard stroke probes.

* Note: When installing the 050-25 sockets or X39-25 termination pins for the dual level testing, the 0.250 [6.35] stroke sockets terminations must be mounted 0.015 [0.38] higher to achieve the 0.150 tip height difference when the fixture is not actuated.