Hello!
I got two old ST412 MFM drives (Seagate ST-4038 and ST-4051) for testing here. Both drives seem to have the same problem - the top PCB is failing. I also have a fully functional ST-4038 here, so I was able to test some combinations of boards and hard disc bodies. The test environment is a 486SX based mainboard with 16MBytes of RAM (4x 4MB 30p SIMM) with an ATI VGA Wonder XL and the second generation IBM Hard Disc Controller from the 5170. I also used another controller (WA6V WA3V) with no other experiences.
At first I tested both defective drives with their original top PCBs. Both drives spin up and unlock the head sled - but with some heavy noise (sounds like the head sled harshly smashes against the body of the hard drive). Then nothing else happens. My functional ST-4038 spins up and unlocks the head sled - but then it take some seconds until the drive gets quiet (I guess it is reading something from the drive). The both defective drives aren't recognized correctly by the computer (Drive error during POST), the functional drive runs fine.
Because of that, I decided to test the PCBs from the defective ST-4038 on my functional ST-4038. The bottom PCB is fully functional with my drive - the top PCB does not run correctly. With the top PCB of the defective drive my drive behaves like the defective one (also makes a really loud, harsh noise during power up).
I also tested the top PCB of my functional ST-4038 on the ST-4051. With this combination, the ST-4051 runs really nice.
What can I do to repair the both defective boards of this two drives? I recognized that some users here also had defective top PCBs on the ST-4038.
Many thanks!
Best regards, Xaar.
PS: I am sorry for my poor English. I am working on it!
I got two old ST412 MFM drives (Seagate ST-4038 and ST-4051) for testing here. Both drives seem to have the same problem - the top PCB is failing. I also have a fully functional ST-4038 here, so I was able to test some combinations of boards and hard disc bodies. The test environment is a 486SX based mainboard with 16MBytes of RAM (4x 4MB 30p SIMM) with an ATI VGA Wonder XL and the second generation IBM Hard Disc Controller from the 5170. I also used another controller (WA6V WA3V) with no other experiences.
At first I tested both defective drives with their original top PCBs. Both drives spin up and unlock the head sled - but with some heavy noise (sounds like the head sled harshly smashes against the body of the hard drive). Then nothing else happens. My functional ST-4038 spins up and unlocks the head sled - but then it take some seconds until the drive gets quiet (I guess it is reading something from the drive). The both defective drives aren't recognized correctly by the computer (Drive error during POST), the functional drive runs fine.
Because of that, I decided to test the PCBs from the defective ST-4038 on my functional ST-4038. The bottom PCB is fully functional with my drive - the top PCB does not run correctly. With the top PCB of the defective drive my drive behaves like the defective one (also makes a really loud, harsh noise during power up).
I also tested the top PCB of my functional ST-4038 on the ST-4051. With this combination, the ST-4051 runs really nice.
What can I do to repair the both defective boards of this two drives? I recognized that some users here also had defective top PCBs on the ST-4038.
Many thanks!
Best regards, Xaar.
PS: I am sorry for my poor English. I am working on it!