P70 DISK OR DISKETTE ERRORS

P70 DISK OR DISKETTE ERRORS

PURPOSE:
Prevent internal power supply RFI (radio frequency interference) from affecting data and program transfers between the system and its fixed disk and diskette drive.

PHYSICAL CHECK:
Systems experiencing data transfer read or write errors such as: CRC checks, post 601, 602, 10480, 10481, 10490 and 10491 errors, or other system hangs and lockups during data transfers are eligible for this ECA.

PREREQUISITES:
P70 systems below serial number xx-xx50000 should also be serviced if a multi-tasking operating system is installed.

DETAIL:
Some 8573 power supplies may transmit RFI that interferes with diskette and fixed disk operation. This RFI signal could affect any 8573 system.

The types of problems that may occur include, but are not limited to the following:

  1. Installing programs or transferring data to the fixed disk drive from any source (E.G. internal or external diskette drive, tape drive etc.)

  2. Backing up data from the disk to diskette or any other media.

  3. Installing programs, data, or operating systems from diskette to the system.

  4. Loading programs, data, or operating systems from diskette or disk to the system.

  5. Saving information running on the system to diskette or fixed disk.

IMPORTANT:
IF THE RFI LEVEL IS HIGH ENOUGH TO CAUSE A PROBLEM DURING DATA TRANSFER AN ERROR WILL OCCUR.

COPPER TAPE KIT FRU P/N07G1680
The kit contains a diagram and twelve inches of copper tape needed for one power supply. To install the copper tape lift the clear plastic shield covering the side and top of the supply. Install the 1 inch wide copper tape length wise across the top and side of the supply so it covers the seam opening. This tape will prevent RFI from escaping from any space between the top and side covers by ensuring conductivity between these two surfaces. RFI transmissions can escape between two electrically insulated pieces of conductive material.

Note:
The rear vent holes are electrically connected to each other so the RFI can not pass through them.


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