seagate 7200.10 question

[BCnVa]

This is my first question here ( Be gentle ) but have been reading and learning for awhile
I have a seagate 7200.10 500 gb drive that needs a head stack replacement. I have not worked on a seagate before and while testing on similar seagate drives I find that I run into a problem each time.
Each time I remove the preamp module from it's slot I will get a PCB failure. (I have not yet removed the heads from the platters) I do not believe I have done any damage to the ribbon connected to the module.
Am I missing something here? I am not as experienced as many on this forum but this is not my first head replacement either.

Thanks

[BlackST]

Have you ever heard about static?

[BCnVa]

BlackST.
Thanks for the quick reply.
I have. I am well grounded.
If you are referring to me damaging the PCB with a static discharge...I neglected to state that I tested the PCB on my donor drive and found that it is working properly. If the module has become damaged due to static, I'm not sure how to eliminate this issue.
Any other suggestions?

[BlackST]

It's not exactly the pcb. GMR sensors (heads) are designed for signals in the picovolt range. Either you destroy something (i.e. the flex) or you damage the whole preamp. At PCB level the signal is pre-amplified and the preamp outputs are sufficiently "user-proof" but at headstack level, it's not. When you remove the PCB (of course you do) you remove the ground connection between preamp and the rest... Have you ever worked with microwave cavities (gunn and schottky diodes) ? If the answer is YES... you know what I'm meaning.
I have a static free workstation and I have never had issues, and it's nothing "exceptional"... however, seagate drives are not a problem in transplanting HSAs, so I'm quite sure you do something wrong or use the wrong tools / instruments.

[BCnVa]

BlackST

Good information. I was sure that I had the static issue handled but when easy things go wrong it's normally something simple missed.

Thanks for your time and help