JBL SCS 135, Руководство по обслуживанию

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SCS135
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Test Set Up and Procedure
Equipment needed:
• Function/signal generator/sweep generator
• Integrated Amplifier
• Multimeter
• Speaker cables
General Unit Function (UUT = Unit Under Test)
1) From the signal generator, connect one line level (RCA) cable to the Subwoofer Line Level Input jacks L/R
on the UUT. Use a Y-cable from a mono source if necessary to connect to both inputs. Do not connect to
the single SUB input.
2) On the front of the unit, turn the LEVEL control full counterclockwise.
3) Turn on generator, adjust to 100mV, 50 Hz.
4) Plug in UUT; turn the power switch ON. LED should be Red. Turn LEVEL control full clockwise (MAX)
5) LED should now be Green; immediate bass response should be heard and felt from port tube opening.
6) Turn off generator, turn VOLUME control fully counterclockwise, disconnect RCA cable.
7) Connect one pair of speaker cables to Speaker Level input terminal (IN) on UUT. Cables should be con-
nected to an integrated amplifier fed by the signal generator.
8) Turn on generator and adjust so that speaker level input at the amplifier is 2.0V, 50 Hz. Turn LEVEL con-
trol full clockwise.
9) Green LED should light, immediate bass response should be heard and felt from the port tube opening.
Sweep Function
1) Follow steps 7-9 above, using a sweep generator as a signal source.
2) Sweep generator from 20Hz to 300Hz. Listen to the cabinet and drivers for any rattles, clicks, buzzes or
any other noises. If any unusual noises are heard, remove woofers and test.
Driver Function
1) Remove woofer from cabinet; and - wire clips.
2) Check DC resistance of woofer; it should be 3.4 ohms ±10%
3) Connect a pair of speaker cables to driver terminals. Cables should be connected to an integrated amplifi-
er fed by a signal generator. Turn on generator and adjust so that speaker level output is 5.0V.
4) Sweep generator from 20Hz to 1kHz. Listen to driver for any rubbing, buzzing, or other unusual noises.
SIGNAL
GENERATOR
AMPLIFIER
AC VOLT
METER (10V)
SUB135
UNDER TEST
SPEAKER
OUTPUT
FROM
AMPLIFIER
I
CAUTION
RISK OF ELECTRIC SHOCK
DO NOT OPEN
AC 120V-60Hz
200 Watts
00365