The Centalic PQ50-A-4GG is a spring-loaded in-circuit test probe for fixtures on 1.27 mm (50 mil) centres, running in an RQ50 receptacle pressed into the probe plate.
The A head is a cupped (concave) tip 0.90 mm across. The cup captures a round target and holds it centred, which makes this the probe to use against solder bumps, wire ends, component leads and via fill — anywhere a flat or pointed tip would slide off. On flat pads a needle or serrated head will give a more repeatable contact. The 4 oz (122 gf) spring is the mid force of the PQ50 range.
Cupped (concave) tip, Ø0.90 mm; plunger diameter 0.50 mm, barrel diameter 0.78 mm
Recommended minimum centre spacing 1.27 mm (50 mil); mounting hole Ø1.0 mm
Rated stroke 4.30 mm, full stroke 6.35 mm
Spring force 122 gf (4 oz)
Current rating 3 A continuous; contact resistance 60 mΩ
Barrel and receptacle bronze, gold plated; plunger BeCu; spring music wire, gold plated
