USER MANUAL, MSD-4, PT# 101012
P a g e
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4
EAST COAST DATACOM, INC.
been corrected by the user. All other DTE's will continue to be serviced by the MSD.
NOTE:
Anti
‐
streaming
is
not
functional
in
Or
‐
Mode
2.7.2 Manual DTE Removal
The MSD-4 incorporate circuitry that will
manually
remove a terminal from service. Simply push
the associated push-button switch for the sub-channel that you wish to remove from service on
the front panel. All other sub-channels will continue to operate as normal.
2.7.3 Unexplained Streaming Terminals
Many different types of terminals have been manufactured over the years. A typical problem is
unexplained lockup or lockout problems. The most common cause is when, four terminals are
running just fine and when one of the terminals is powered down, the remaining terminals are
locked out of service. This may be explained by a missing or incorrect Termination Resistor that
has been overlooked by your terminal manufacturer. This is the main reason that Anti-
Streaming circuitry has been designed into the MSD-4 as well a 22k pull-down resistor is on each
sub-channel’s RTS leads, for long unterminated cables.
2.8
DIAL
MODEM
SUPPORT
The MSD-4 support dial modem applications by connecting the DTR jumper pin for each DTE
port. The jumper pin enables/disables the DTR signal to each DTE sub-channel. If a dial modem
is used with terminals, all DTR jumpers must be enabled.(JP15-JP-18.
2.9
CASCADING
OR
CONCATENATION
The MSD-4 supports cascading and the user simply needs to use DB-25 Male to Male straight
through shielded cables.
Sub
‐
channel
Port
1
should be used as the concatenation port.
CHAPTER 3 - INSTALLATION
3.1
VOLTAGE
SELECTION
It is
very
important to check that the unit is set to the correct voltage setting for your application
before applying AC power. Located on the rear of the unit you will find a rotary 110/220 VAC
switch. Using a coin or small screwdriver,
gently
turn the switch to the appropriate power
position as required for your installation (110 or 220 VAC).
3.2
VOLTAGE
SELECTION
FUSES
Located on the back of the product you will find an IEC Power receptacle. This receptacle
contains a fuse drawer. Two (2) fuses are located in this compartment.
Little Fuse Part #: 0.160ma = 218.160 for 110VAC or 0.080ma = 218.080 for 220VAC
Shurter, Inc. Part #: 0.160ma = 034.3109 for 110VAC or 0.080ma = 034.3106 for 220VAC
Disconnect Power Before Servicing - Coupez l'alimentation avant l'entretien
