Studio Technologies 55 2005 - Manual (Page 23)

Model 55/56 User Guide Issue 5, August 2005
Studio Technologies, Inc. Page 23
many MIDI cables only have three conduc-
tors! You must use a 5-conductor MIDI-
style cable or the Model 56 will not power
up and function. Five conductor MIDI
cables are not hard to fi nd, but you must
ask for them and ensure that you get what
you asked for. Be warned!
Over Current LED
During normal operation the Over Cur-
rent LED, located on the front panel of
the Model 55, should not light. It will light,
fl ashing on and off, in response to prob-
lems with the Model 56 Control Console
and/or the Talent Amplifi er output.
The Over Current LED will light if the
power source that supplies the Model 56
Control Console is loaded to exceed its
maximum output current. The most com-
mon reason for an over current condition
would be a shorted 5-conductor MIDI-style
interconnecting cable. A major fault in the
Model 56 would also cause the LED to
light.
The Over Current LED will also light if the
talent amplifi er output is loaded to exceed
its maximum output current. The most
common reason for an over current condi-
tion would be a shorted interconnecting
cable. Also, connecting more than the
specifi ed maximum of four Model 35 Tal-
ent Amplifi ers can also cause the LED to
light. Possible, but not likely, would be a
fault condition in a Model 35.
If the Over Current LED does light, trouble-
shooting should prove quite simple. Be-
gin by disconnecting the cables that are
plugged into the Control Console/MIDI In
and the talent amplifi er output connectors.
Perform the disconnection directly on the
Model 55’s back panel. The LED should
stop lighting. Now reconnect to Control
Console/MIDI In. If the LED again lights,
follow this paragraph. If the LED does not
light, skip to the next paragraph. Check the
interconnecting cable that links the Model
55 with the Model 56 Control Console.
You need to determine where the short
circuit condition is located. The Model 55
will not be damaged if the Over Current
LED is lighting so you should use it to help
you locate the fault. In just a few minutes
you should be able to isolate exactly if the
cable or the Model 56 is causing the prob-
lem. Replace the cable if it proves to be
bad—remember you’ll need a MIDI-style
cable with all fi ve conductors connected.
If the Model 56 appears to be at fault, it
will need to be returned to the factory for
repair.
If the LED did not light when you recon-
nected to Control Console/MIDI In, recon-
nect to the talent amplifi er output. The LED
should now light, identifying that the prob-
lem is with the talent amplifi ers or associ-
ated cabling. In most cases you will fi nd
that a cable is at fault. If a talent amplifi er
is found to be at fault, it will need to be
returned to the factory for repair.
Input Data LED
The Input Data LED lights only when data
is received that is valid for the Model 55.
The Model 55 uses MIDI system-exclusive
messages to perform all operations. When
the Model 56 Control Console is connect-
ed to the Model 55, the LED will light any
time the Model 56 generates data. This is
because the Model 56 will only generate
data that is compatible with the Model 55.
If you are not using the Model 56, and
instead are supplying MIDI data using
another device, the LED should prove
extremely useful when troubleshooting.
Only when the MIDI data conforms to the