Multitech MMH956K, MMV1656K Product Update

Model MMH956K/MMV1656K
56K Internal DSU Upgrade Kit
Product Update
PN S000339A
4/02/04

This Product Update covers installing an internal 56K DSU in the MultiMux MMH900 series or the MMV1600/
3200 series. The first procedure covers installing the DSU in an MMH900 series and the second procedure
covers installing the DSU in an MMV1600/3200 series.

MMH900 Series DSU Upgrade Procedure

Step Procedure

1 Check the contents of your upgrade kit to ensure that it contains the parts listed below:

a) Screwdriver
b) Mounting screws (2)
c) MMH956K DSU

d) Serial tag label
2 Turn the MultiMux power switch to OFF and unplug the MultiMux pow er cord from the wall outlet.
3 Turn the MultiMux upsidedown and remove the f our scre ws securing the cover to the base.

4 Slide the cover off the base.

Cover

Mounting
Screw
(x4)

MMH900 Cover

5 Plug in the Internal 56K DSU to the connector on the motherboard and the back 6-pins on the side 10-

pin connector. Be careful to align the 6-pins of the DSU with the pins on the 10-pin connector that

are the farthest from the modem 96-pin connector.

Modem Mounting
Screws

56K Internal

Motherboard

1 2 3 4 5 6 7 8

DSU

OTHER RKWL14.4

1 2 3 4

Base

Modem 10-pin
Connector

V.35 V.24

V29/V33

2834

Modem 96-pin
Connector

V.29/V.33
Shunt

2834
Shunt

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6 Secure the DSU to the base using the two plastic mounting screws provided in the upgrade kit. One of

the screws goes into the connector and the other one into the standoff on the motherboard.

7 Set switch position 2 of the 8-position DIP-switch to the OPEN (UP) position.
8 Slide the cover onto the base and replace the f our cover screws.
9 Attach the internal DSU serial tag to the bottom of the MultiMux cabinet next to the existing serial tag(s).
10 Connect the RJ48 cable provided in the upgrade kit to the COMPOSITE LINK INTERNAL DIGITAL DSU

connector on the backpanel of the MultiMux.

11 Connect the other end of the RJ48 cable into a telephone wall jac k and plug in the power cord.
12 Refer to Chapter 5 of your MultiMux Owner's Manual to configure y our internal DSU .

MMV1600/3200 Series DSU Upgrade Procedure

Step Procedure

1 Check the contents of your upgrade kit to ensure that it contains the parts listed below:

a) Screwdriver
b) Mounting screws (2)
c) MMH1656K DSU
d) Serial tag label

2 Turn the MultiMux power switch to OFF and unplug the MultiMux pow er cord from the wall outlet.
3 Loosen the four quarter-turn-fasteners on the front panel and remove the front panel.
4 Loosen the two pc board chassis lock screws on the back panel.

PC Board Chassis Lock Screws

5 Pry up on the two pc board chassis lock screws to unlock the pc boards in the chassis. Temporarily

retighten these screws while in the up position.

6 Disconnect the pc board power cable from the pow er supply.
7 Partially pull out all the pc boards in the chassis just past the inside edge of the data and address ribbon

cable connectors. It may require a slight forward tug on the voice/fax board (if installed) to free it from its
board edge connector while pulling the other boards forward.

8 Disconnect the control ribbon cable from the Aggregate board.
9 Disconnect the data and address ribbon cable connector from the Aggregate board.

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