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The Hicom 100 series telephones above are (from left to right) Directory Keystation (Set 191 - Ultraset Memory), Expansion Module (Set 190 Ultraset T24 CD - used with Directory Keystation), DSS unit (Set 150 - used with Executive Keystation), Standard Keystation (Set 150 T16) and Executive Keystation (Set 151 T28)

The HICOM 120 (pictured right back) is a stored program controlled (S.P.C.) key telephone systems utilising micro-processor control and analogue switching, (2 Wire), with analogue speech transmission.

The central control unit is wall mounted and contains the 240V AC power supply with all switching and control elements.

The HICOM 120 can be equipped for a maximum of 8 exchange lines and 24 extensions.

There are special HICOM telephones. The Keyset 1 (see NTX24 ), Set 151 T28 (far right), Set 151 T16 (middle) or Set 191 (left)  instruments may be supplied.  DSS consoles are also available - Set 190 (front left) & Set 150 (middle rear).

All the system phones are 4 wire fed and the C & D wires are protected from short circuit by 200ma delay action fuses (F11 & F12 on LTB 1 & 2 boards).

All power requirements are provided from the 240V ac mains, maximum power consumption is 160 watts. During periods of power failure, 4 exchange lines are switched to emergency telephones.

The apparatus must be connected to the PSTN, host CPA, subsidiary CRA and analogue private circuits by connecting to the NTP connection box which is separately mounted.

The system has four card slots. The first contains the CPU card, the second slot must contain a 4+8 card, the third slot can contain a 4+8 or 0+8 card whilst the fourth slot can only contain a 0+8 card.

Programming can be completed via a display terminal connected to Port 00 of the system or by a PC with PCSAT software installed.

Meter pulse boards (GEE) can be installed and these are connected next to the MDF.  Each GEE card supports two exchange lines.

When installing the system, it must be remembered that the card frame swings outwards and space must be therefore left to the right of the system to allow the card frame to swing 90 degrees to the right.

The 110, 120, 125 & 130 systems were superseded by 150 & 100E series

do not disturb
call forwarding
fully hands free
follow me
DSS console connection
call pick-up
call barring
caller ID
hold display messages
call display call cost
camp on
ringer volume and pitch control
call park
broker's call
message waiting
paging 12 dedicated keys
voice call 14 programmable keys
speed dialing - 800 memory store for names
auto call back
terminal lock
QWERTY keypad for input
extension PIN security code names addresses and telephone
account codes numbers
least cost routing
night service
hotel functions
music on hold
hands free
hunt groups
manager/secretary working caller ID
V24 interface display messages
optional hotel package display call cost
time & date alarm
ringer volume and pitch control

room status
8 pre-programmable keys
baby monitor
direct internal and last/save number redial
external line access
hands free answer
itemised billing monitor
ringer volume and pitch control

Additional Information

Line Jack Wiring for Featurephones (use Secondary sockets)

MDF Connection Wire Colour LJU Connection
A BLUE/white 2
B WHITE/blue 5
C ORANGE/white 3
D WHITE/orange 4

For POT phones, just connect the A and B wires to terminals 2 and 5 in a master socket.

MOH Switch settings

DIP switch Setting Mode
S700 Open MOH Melody 1
S700 Closed MOH Melody 2
S701 Open (1-2) Internal Melody R70 - Volume Control (pot)
S701 Closed (2-3) External Melody R71 - Volume Control (pot)

External MOH is connected to X20 (moh1/moh2) on the motherboard.

Cover removal and access to system
Remove the single Torx screw from the bottom of the cover.  The lower edge of the cover is then pulled forwards and this will then allow the top edge of the cover to lift upwards slightly, releasing the top of the cover.  The cover is now free and can be removed.

The card frame is hinged on the right hand side and restrained by a Torx screw located centrally, towards the rear, at the top of the frame.  Remove this screw and the frame will swing to the right exposing the MDF.

Technical Pages

System Wiring

System Programming Manual


Set 191 - Ultraset Memory connected to a Set 190 - Ultraset T24 CD
Set 151 T28 connected to a Set 150
View with cover on
View of main boards and PSU to the right
The memory battery can be seen to the lower left (Orange in colour)
View of PSU - it plugs into a small backplane located behind the metal plate above the PSU


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Last revised: December 18, 2011