HARMAN KARDON BU1
Manual de Servicio

Powered Subwoofer

BU1

BU1 TEST PROCEDURE

TEST PROCEDURE
Equipment needed:
n n n n

7. Turn on generator and adjust so that speaker level output
is 1.0V, 50 Hz. Turn VOLUME control full clockwise. be heard and felt from port tube opening.

8. Green LED should light, immediate bass response should

Function/signal generator/sweep generator Integrated Amplifier Multimeter Cables - line level (RCA) and speaker cables

Sweep Function 1. Follow steps 1 - 4 above, using a sweep generator as a
signal source.

General Function UUT = Unit Under Test 1. Connect both right and left line level inputs (RCA) to

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 driver and test.

signal generator and UUT. Use Y-cable if necessary from mono source. VOLUME control should be full counterclockwise.

2. Turn on generator, adjust to 25mV, 50 Hz. 3. Plug in UUT; red LED should be ON. Turn VOLUME
control full clockwise.

Driver Function 1. Remove driver from cabinet; detach + and - wire clips.
2. Check DC resistance of driver; it should be 3.3 ohms. 3. Connect a pair of speaker cables to driver terminals.
speaker level output is 5.0V. Cables should be connected to an integrated amplifier fed by a signal generator. Turn on generator and adjust so that

4. LED should turn Green; immediate bass response should
be heard and felt from port tube opening.

5. Turn off generator, turn VOLUME control fully
counterclockwise, disconnect RCA cables.

4. Sweep generator from 20Hz to 1kHz. Listen to driver for
any rubbing, buzzing, or other unusual noises.

6. Connect one pair of speaker cables to either high level

input terminal on UUT. Cables should be connected to an integrated amplifier fed by the signal generator.

3