Studio Technologies 93 - Manual (Page 17)

Model 93 User Guide Issue 1, January 2008
Studio Technologies, Inc. Page 17
(master) unit by tapping its power button.
Then press and hold its power button until
the system mode has changed to master-
male active or master-female active. At this
point if the connection is valid data com-
ing from the master Model 93 will “wake
up” the slave unit. The active LED, located
below the BNC connector, on each unit will
flash as data packets move between the
units. Once data link operation has been
confirmed power down the unit designed
as master. The slave unit should also power
down in response to a command from the
master unit.
Note that maintaining a short circuit on
the Model 93’s data link BNC connector
is something to avoid. Due to an idiosyncra-
sy in the operation of the data communica-
tions transceiver integrated circuit an error
in the data link wiring can force the Model
93 to stay in the powered up state. The
10-minute inactivity timer will not be able to
power down the unit; nor will a low-battery-
voltage condition be able to invoke a power
down either. Damage to the battery will
occur if a deep discharge state is reached.
This situation is not something that the
Model 93’s designers are especially proud
of, but they weren’t aware of the condition
until it was too late to make a change. And
contacting the world-class maker of the inte-
grated circuit didn’t get much of a response
except “hmmm…” So in conclusion, as long
as the BNC connector isn’t presented with a
short circuit or a low impedance load condi-
tion things will work fine.
Master/Slave Cable Testing
Once the data link has been established
between the two Model 93 units testing
operation can begin. Start from the condi-
tion of having both units in their powered
down state. Then review the desired testing
scenario, knowing exactly which cable
assembly is going to be tested first. Des-
ignate one of the Model 93s as the master
unit. There’s no requirement as to which
unit is the master and which unit is the
slave. Typically the Model 93 that’s most
conveniently accessible should be the
master unit. For example, when testing W1s
in a stadium, it probably makes sense to
have the master situated in the truck dock
or main wiring location. Then the slave unit
can move among the destination locations
such as the broadcast booth, side of the
field, etc.
Now activate power to the unit that has
been designated as master. Ignore the sta-
tus of the data link active LED and whether
or not the slave unit powers up. Before
these issues come into play a couple of
other things must first be accounted for.
On the master unit, set the cable mode to
match the type of cable to be tested. If, for
example, the cable to be tested has W1
connectors on each end select the cable
mode as W1 to W1. Another example would
be if the cable to be tested has an W1
female on one end that “breaks out” into
twelve XLR males on the other end. This
would necessitate setting the master unit’s
cable mode to W1-F to XLR-M.
The final step is to set the master unit’s
system mode. This is a little tricky to under-
stand but we’ll work through it! Begin by
confirming the exact type of connector that
is to be connected to the master unit. For
example, while the cable mode might be
set for W1 to W1, there’s no requirement as
to which connector end, male or female, is
physically located near the Model 93 that’s
been designated as master. For our exam-
ple let’s specify that an W1 male connector
is on the end of the cable that’s to be at-
tached to the master Model 93 unit. To meet
the needs of this situation, set the master