The Centalic PQ50-H-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 so worn probes can be swapped without rewiring.
The H head is a serrated tip — a flat face cut with teeth. It spreads the spring load over a wider footprint than a needle, so it marks the target less while the serrations still break through oxide and flux film. That makes it the choice for flat pads and larger test points; use the B needle version where the target is a small pad or via. The 4 oz (122 gf) spring is the mid force of the PQ50 range.
Serrated tip; 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
