Ref: 99970051
Title: CS/1 SIO-16 Upgrade Module - pt no 86-0213-00 rev 00
Date: 09/11/89

Copyright 3Com Corporation, 1991.  All rights reserved.

Upgrade Module
SIO-16
September 11, 1989


Part Number: 86-0213-00
               Revision: 00

TO:  CS/1 Users
FROM: 3Com Corporation
SUBJECT: SIO-16 Upgrade Module
DATE: September 11, 1989

The SIO-16 Upgrade Module contains an SIO-16 board to be installed in a
CS/1.  Follow the procedure in this release memo before installing the SIO-
16 board in a CS/1.


 ** CAUTION **

 The SIO-16 test should be performed to ensure that the amount of Radio
Frequency  (RF) emissions or electromagnetic interference from the CS/1 is
minimized.


Continuity Test

1. Using a volt-ohmmeter, check for continuity (must be less than 1 ohm)
between the  upper right jack screw on all of the SBA-16 boards (at J2),
and chassis ground  (card cage, power supply cover, etc.).  See attached
Figure 1.

2. If the resistance reading is equal to or greater than 1 ohm, it is
possible that the  SBA-16 plate is not making good ground contact with the
chassis.  If paint is  present around the hole indicated in Figure 2, use a
spot-facing end mill with pilot  shaft and electric hand drill to remove
the paint.  Figure 3 illustrates an end mill  with pilot shaft, including
dimensions.


Figure 1  Performing the SIO-16 Test


         Check for paint


Figure 2  Chassis Rear Panel


Figure 3  End Mill with Pilot Shaft and Dimensions
