Power Distribution Board
We have recently discovered a problem, on early models of the VX FT /
FTs, in that the terminating resistors (RP1,2,3,4,5 and 6) on the Power Distribution Board
were fitted incorrectly, and also that the switches (SW1, 2 and 3) do not disconnect the
first three terminators from the SCSI BUS correctly. We have since modified the board
(Build Level 4), and also introduced a set of procedures for the installation of drives in
the VX FT / FTs.
1. If the Front Bay ONLY is to be used for installing SCSI devices.
Terminate the SCSI cable in PL1; all the Switches need to be in the ON
position (To the Left), and the terminators RP1,2 and 3 need to be in fitted, with pin 1
to the bottom.
2. If Both Bays with ONE SCSI card are to be used.
First connect the SCSI cable, from the SCSI card, to the drives in the
front bay, then put the end of the cable into PL1. Remove the terminators in RP1,2 and 3,
and move all the switches to the OFF position. Install the second SCSI cable, plugging one
end into PL2, the other into PL3 which is the terminating slot.
3. If Both Bays with TWO SCSI card are to be used.
Connect the SCSI cable from one SCSI card, to the drives in the front
bay, and plug the end of the cable into PL1. The terminators should be inserted into RP1,2
and 3, and all the switches should be in the ON position. Next connect the cable from the
other SCSI card to the drives in the rear bay terminating in PL3.
Note: Remove all terminators from drives fitted in this machine. |
