I've purchased a used P6114B probe for TEK TDS-380 oscilloscope.

I cannot properly compensate it - there are significant overshoots on a square wave compensation signal.
Other probes I have work fine with that scope.

Here is a screenshot : ch1 is a bad probe compensation signal, ch2 a good one


Can anyone suggest what might be the problem?

 

Send it back.

 

Make sure the problem follows the probe (try the bad probe on chan 2) . I have seen problems similar when the BNC center connection didn't make good contact with the center pin of the probe connector. Also have seen problems with the AC/DC switch having bad contact.