Greg Hanks Design BA-660, Руководство по эксплуатации и обслуживанию

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BA660.doc 01/01/97 15 of 25
probably hum badly. In
fixed installations, please
ensure that the only
connection to the shield
of the microphone is
though the signal line
that connects it to the
unit, and not touching
the building steel
through the mic box!
⇒
The line input should
have the shield source’d
at the origination point
and the shield should
drop at the BA-660.
There are internal
provisions for supplying
a shield source from the
BA-660, but this is not
recommended.
⇒
The Insert send sources
the shield. The return
shield is dropped
internally. If this is a
problem, correct it by
tying the shield to the
chassis at the returning
signal source.
⇒
The side chain insert
return shield is also floating
and should be referenced at
the driving source.
•
Rear Panel Ground connections
There are two 5 way binding
posts on the rear of the unit.
The green one is attached
directly to the chassis, and
the Black one is tied directly
to Tech Earth internally. The
link that is provided external
to the chassis is the only
point that the chassis and
Tech Earth, (Audio Com-
mon) are brought together.
This connection must be
maintained either through
the link or via the studio
wiring. Your technical
consultant will be your best
guide to determining the
correct installation method
for your room.
⇒
Shields and the output. The
shield at the Line Output is
carried from pin 1. This is
the source of the shield for
the output wire, but should
not be carried through the
input of the driven load.
•
Input and Output balance
Both the Mic, Line, insert
return, side chain insert and
the Line Output circuits are
balanced and floating. The
Insert send is balance
⇒
When taking a single
ended input, always
bring the grounded line
to ground at the signal
source. This will treat
the line as a balanced
line and reduce the
hum induction.
⇒
The output of this
device must be brought
to ground at pin 1 of
the output connector if
it is to be unbalanced.
The output mode
switch must be switched
to the correct position.
In un-balanced
operation, if the switch
is in the wrong position