53230A counter CH1 input trace fails!?

[awallin]

We just had the second failure of this kind:
53230A counter CH1 input just stops working all of a sudden. Inspection of the board reveals a thin trace just after the input-BNC that is broken. The fix is to add a wire from the input-BNC to the next smd-pad which happens to be unpopulated.

Anyone seen this before on the 53230A or its sister models? We have one more 100ps version and maybe a third 20ps - I'm now almost expecting them to fail in the same way since two units have already shown this 

Chemical corrosion? Mechanical stress from the BNC? Other ideas?

Anders

[SeanB]

Probably the inner pin flexing as connectors are mated and disconnected. The stress is transmitted to the board. Nice fix with the wire, though I would have used a thin strip of foil to provide a more compliant connection with low inductance.

[free_electron]

how much power are you blasting in that thing ? that's a fusable trace ..