MCi JH-400B Series Technical Manual page 19

6.0
TROUBLESHOOTI~S
6,1
GENERAL INSTRUCTIONS
Host of the process of troubleshooting the JH-400B COUSOLE can
be accomplished through the PATCH BAY. The process is called
PROGRESSIVE ISOLATION, and use the FLOW CHART, page 3-7 as a
guide.
The FLOW CHART is your most reliable guide to the relative
positions of the PATCH POINTS and the FUNCTIONS found in each
module. With proper use of the built-in signal generator, the
patch bay, and the flow chart, you should be able to isolate any
problem within a few components before you remove a single panel.
There are two preliminary steps which are important enough to be
called RULES to be followed BEFORE you start troubleshooting~
1.
FAMILIARIZE YOURSELF with the SIGNAL FLOW in the console.
A. There are THREE !10DES of operation in the JH-400B. They
are fully explained on pages 3-1 through 3-3 of this
manual.
FOLLOW THE SIGNAL FLOW FOR EACH MODE,
B. Be sure that you know the ORDER in which the signal
passes through each FUNCTION.
{i.e.- Channel Fader, EQ circuit,
Pan controls, etc.)
2. FA~ULI~RI ZE YOURSELF with the position of each PATCH POINT.
A. Patch Bay information is available on page 8-5 of this
manual.
B. The FLOW CHART on page 3-7 shows the position of each
patch point - LOCATED ON THE SIGNAL PATH.
EVERYTHING NEEDED TO PREPARE YOURSELF TO LOCATE TROUBLE IN THE
CONSOLE IS AVAILABLE IN THIS t'iANUAL.
6.2
SIGNAL SUBSTITUTION
A. Use the AUDIO GENERATOR located in the
CO~ll1
module as a signal
source. The "TRI<S" and "~UX" switches on this module connect the
signal to the Channel Buses, or to the Quad aix Buses.
You may also pick up this signal at the "OSC" jack in the Patch
Bay.
B. USE THE FLOW CHART to follow the signal flow through the
console. LOCATE THE SPECIFIC SECTION where the signal is lost.
JH-400B
Page 6-1