The most vexing thing about the P6042 is how fragile the probe is mechanically, a very short drop on a hard surface can permanently damage the transformer inside the probe, and huge DC offset is the result. It's not repairable.
I bought a perfect P6042 almost 10 years ago and after an accidental drop, *balfap*, it was useless.
Through sheer luck I found a complete transformer replacement kit for 23$. This has never happened again!
I also found that one NOS cable assembly, that also never happened again.
The prices for P6042s are all over the place from 100$ to over 1000$. It is unpredictable.
*"balfap" sound effect courtesy of Don Martin