Bose 802c User Manual

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®

®

802C System Controller

Original and SMD Version

Units with serial numbers beginning with 100000 are the original 802C's. Units with serial numbers beginning with 200000 are thenew SMD 802C's.

©1997 Bose CorporationService Manual

1

Part Number 129292 REV 03

 

 

Contents

 

Safety Information ............................................................................................................................

3

Electrostatic Discharge Sensitive (ESDS) Device Handling ........................................................

4

Specifications ...................................................................................................................................

5

Technical Description ......................................................................................................................

6

Disassembly/Assembly Procedures ..............................................................................................

7

Figure 1.

Locking Tab Screw Location .............................................................................................

7

Figure 2.

Original 802C PCB Exploded View ...................................................................................

8

Figure 3.

SMD 802C PCB Exploded View .......................................................................................

8

Test Procedures ..........................................................................................................................

9-10

Part List Notes ................................................................................................................................

11

Main Part List ..................................................................................................................................

12

Figure 4. Main Parts Exploded View ..............................................................................................

13

Electrical Part List .....................................................................................................................

14-17

Voltage Conversion Instructions ..................................................................................................

18

Figure 5. Voltage Conversion Diagram ..........................................................................................

18

Figure 6.

Top Cover Connection Diagram ......................................................................................

19

2

SAFETY INFORMATION

1. Parts that have special safety characteristics are identified by the

 

 

symbol on

 

 

schematics or by special notes on the parts list. Use only replacement parts that have critical characteristics recommended by the manufacturer.

2.Make leakage current or resistance measurements to determine that exposed parts are acceptably insulated from the supply circuit before returning the unit to the customer. Use the following checks to perform these measurements:

A.Leakage Current Hot Check-Withthe unit completely reassembled, plug the AC line cord directly into a 120V AC outlet. (Do not use an isolation transformer during this test.) Use a leakage current tester or a metering system that complies with American National Standards Institute (ANSI) C101.1 “Leakage Current for Appliances” and Underwriters Laboratories (UL) 1492 (71). With the unit AC switch first in the ON position, then in the OFF position, measure from a known earth ground (metal water pipe, conduit, etc.) to all exposed metal parts of the unit (antennas, handle bracket, metal cabinet, screwheads, metallic overlays, control shafts, etc.), especially any exposed metal parts that offer an electrical return path to the chassis. Any current measured must not exceed 0.5 milliamp. Reverse the unit power cord plug in the outlet and repeat test. ANY MEASUREMENTS NOT WITHIN THE LIMITS SPECIFIED HEREIN INDICATE A POTENTIAL SHOCK HAZARD THAT MUST BE ELIMINATED BEFORE RETURNING THE UNIT TO THE CUSTOMER.

B.Insulation Resistance Test Cold Check-(1) Unplug the power supply and connect a jumper wire between the two prongs of the plug. (2) Turn on the power switch of the unit. (3) Measure the resistance with an ohmmeter between the jumpered AC plug and each exposed metallic cabinet part on the unit. When the exposed metallic part has a return path to the chassis, the reading should be between 1 and 5.2 Megohms. When there is no return path to the chassis, the reading must be “infinite”. If it is not within the limits specified, there is the possibility of a shock hazard, and the unit must be repaired and rechecked before it is returned to the customer.

PROPRIETARY INFORMATION

THIS DOCUMENT CONTAINS PROPRIETARY INFORMATION OF BOSE® CORPORATION WHICH IS BEING FURNISHED ONLY FOR THE PURPOSE OF SERVICING THE IDENTIFIED BOSE PRODUCT BY AN AUTHORIZED BOSE SERVICE CENTER OR OWNER OF THE BOSE PRODUCT, AND SHALL NOT BE REPRODUCED OR USED

FOR ANY OTHER PURPOSE.

3

ELECTROSTATIC DISCHARGE SENSITIVE (ESDS)

DEVICE HANDLING

This unit contains ESDS devices. We recommend the following precautions when repairing, replacing or transporting ESDS devices:

Perform work at an electrically grounded work station.

Wear wrist straps that connect to the station or heel straps that connect to conductive floor mats.

Avoid touching the leads or contacts of ESDS devices or PC boards even if properly grounded. Handle boards by the edges only.

Transport or store ESDS devices in ESD protective bags, bins, or totes. Do not insert unprotected devices into materials such as plastic, polystyrene foam, clear plastic bags, bubble wrap or plastic trays.

CAUTION: THE 802® C SYSTEM CONTROLLER CONTAINS NOUSER-SERVICEABLEPARTS. TO PREVENT WARRANTY INFRACTIONS, REFER SERVICING TO WARRANTY SERVICE STATIONS OR FACTORY SERVICE.

4

 

 

SPECIFICATIONS

Input Connections:

 

 

 

One (1) balanced female XLR connector

 

 

(per channel)

 

 

 

One (1) unbalanced 1/4" phone jack

Output Connections:

 

 

 

Two (2) 1/4" phone jacks per channel

(per channel)

 

 

 

(outputs used depend upon mode selected)

Input Impedance:

 

 

 

Balanced input, 4kΩ

 

 

 

 

Unbalanced input, 42kΩ

Electronic Crossover

 

 

 

 

Frequency:

 

 

 

180Hz (bi-amplifiedmode only)

Maximum Output Level:

 

 

 

4 Volts (+12dB into 600Ω, 50Hz-16kHz)

Total Harmonic Distortion:

 

 

 

Less than .02% at 1 Volt (0dB)

 

 

 

 

Less than .2% at 8 Volts (18dB)

Output Noise:

 

 

 

Less than 20uV (-9dBV)A-weighted

Power Requirements:

 

 

 

120 Vac, 50-60Hz,3.5 Watts

 

 

 

 

220 Vac, 50-60Hz,(European)

 

 

 

 

100 Vac, 50-60Hz,(Japan)

Dimensions:

 

 

 

1 3/4"H x 10" W x 5" D

 

 

 

 

(4.4 x 25.4 x 12.7 cm)

Weight:

 

 

 

1.97 lbs (.895 kg)

5

TECHNICAL DESCRIPTION

The 802® C System Controller is a sophisticated signal processing device which combines the functions of three equalizers, an automatic switching circuit, and an electronic crossover. The 802C system controller automatically selects the proper crossover function and equalization curve for a given system application through use of a switching network operating in conjunction with the unit's output jacks. In addition to signal routing based on equalization requirements, the switching network indicates mode of operation on its front panel. The front panel also includeshigh-cutandlow-cutswitches which decrease line output by 4dB at 55Hz and by 10dB at 16kHz. Sharp subsonic and ultrasonicband-limitingfilters reduce power waste, stage noise,high-frequencyinstability, and interference. The 802C system controller retains the compact dimensions of its predecessor, the Bose® 802E active equalizer, and fits into one space of a standard 19" equipment rack with the optionalRMK-8Rack Mount Kit.

In an on-goingprocess of manufacturing updates, as technology permits, Bose Corporation has begun using SMD (surface mount devices) components on its 802C controller. The new SMD components are such a space saving feature that this new version permits us to eliminate the"piggy-back"PCB and place all electronics on one single printed circuit board. This manual will identify the different procedures, PCB layouts, and components where necessary.

There is no difference in the operation or function between the original 802C and the 802C SMD units.

6

DISASSEMBLY/ASSEMBLY PROCEDURES

Note: Refer to the Figures (2 and 3) for the following procedures.

1.Top Cover Removal

1.1Remove the four screws (two located at the rear of the unit and one located on each side of the unit) that secure the top cover to the chassis.

1.2Lift the rear of the top cover slightly and slide it forward until the front of the top cover is clear of the switches.

2.Top Cover Replacement

2.1Align the front of the top cover with the switches and LED's and slide the cover into place.

2.2Secure the top cover into place.

3.302EQ ("piggy-back")PCB Removal

Note: The original 802C has two PCB's. The following procedure will discuss the removal of the"piggy-back"PCB.

Note: The"piggy-back"PCB does not need to be removed when removing the main PCB.

3.1Perform procedure 1.

3.2Locate the four plastic stand-offs(three are located in the corners of the PCB and one is located between C125 and C225).

3.3With small needle-nosepliers, squeeze the retaining tab of eachstand-offwhile gently lifting up on the PCB to release the lock. Grasp the PCB at the middle of each side and lift the PCB off of the connectors.

4.302EQ ("piggy-back")PCB Replacement

4.1Replace the "piggy-back"PCB (on the original 802C controller) by placing the board over the connectors and pushing the board down onto thestand-offs.

4.2Perform procedure 2.

5.Main PCB Removal

5.1Perform procedure 1.

5.2Remove the 6 knurled nuts securing the input and output jacks to the chassis.

5.3Remove the 5 screws that secure the main PCB to the chassis.

5.4On the rear of the unit, at the XLR jacks there is a small hole with a locking screw inside (see Figure 1). Insert a small flathead screwdriver into the hole and rotate the locking screw 1/8 turn counterclockwise to release the locking tab.

5.5Lift the front of the PCB up slightly. Gently pull the PCB out while pushing on the center of the XLR jacks.

6.Main PCB Replacement

6.1Carefully slide the PCB into the chassis while aligning the XLR jacks into their housing.

6.2Lock the XLR jacks into place by inserting a small screwdriver into the small hole in the XLR jack and rotate the screw clockwise 1/8 turn.

6.3Replace the 5 screws that hold the PCB into place in the chassis.

6.4Perform procedure 2.

Figure 1. Locking Tab Screw Location

7

Figure 2. Original 802C PCB Exploded View

Figure 3. SMD 802C PCB Exploded View

8

TEST PROCEDURES

1.Mode Indicator Test

1.1Depending on the output jack configuration (see top cover diagram on page 17), equalization curves and output vary. You must test all modes of the 802C to assure proper operation.

1.2Perform the test below to verify that the mode select operation is working properly.

Note: You can insert one or both of the output jacks into the unit for this test.

LED Indicator Status

Output

802

Passive

Bi-

Jacks

Full

2-Way

AMP

Inserted

Range

 

 

No Jacks

On

Off

Off

Inserted

 

 

 

Inserted into

On

Off

Off

802 AMP

 

 

 

Inserted into

Off

On

Off

302 AMP

 

 

 

Inserted into

Off

Off

On

802 and 302

 

 

 

AMP

 

 

 

2.802 Full Range Frequency Response

2.1Apply a 750Hz, 500mVrms signal to the input of the 802C.

2.2Reference a dB meter to the 802 AMP output jacks.

2.3Refer to the frequency response table below and verify the response of the unit.

Full Range Frequence Response Table

Frequency

Output

Tolerance

55Hz

+14.0dB

± 1.5dB

30Hz

0dB

± 2.5dB

250Hz

+2.7dB

± 1.2dB

750Hz

0dB

-

 

(reference)

 

3kHz

+2.3dB

± 1.5dB

7.5kHz

+12.0dB

± 1.5dB

15kHz

+16.9dB

± 1.8dB

Note: Set both the Lo and Hi cut switches IN for the following response table.

Lo and Hi Cut Switch Response Table

Frequency

Output

Tolerance

55Hz

+9.3dB

± 1.8dB

750Hz

0dB

-

 

(reference)

 

15kHz

+6.9dB

± 2.0dB

3.302 Passive Frequency Response

3.1Apply a 750Hz, 500mVrms signal to the input of the 802C.

3.2Reference a dB meter to the 302 AMP output jacks.

3.3Refer to the frequency response table below and verify the response of the unit.

Passive Frequency Response Table

Frequency

Output

Tolerance

30Hz

-8.8dB

± 2.5dB

55Hz

+6.2dB

± 1.5dB

150Hz

-3.2dB

± 1.5dB

250Hz

+3.2dB

± 1.8dB

750Hz

0 dB

-

 

(reference)

 

3kHz

0.9dB

± 1.5dB

15kHz

+15.3dB

± 1.8dB

4. Bi-AmpFrequency Response

Note: This test is performed with both the 802 AMP and the 302 AMP output jacks used at the same time.

4.1Apply a 750Hz, 500mVrms signal to the input of the 802C.

4.2Reference a dB meter to the 802 AMP output jacks (while in the Bi-Ampmode).

4.3Refer to the frequency response table below and verify the response of the unit.

802 Bi-AmpFrequency Response Table

Frequency

Output

Tolerance

55Hz

-20.1dB

± 2.5dB

230Hz

+2.6dB

± 1.8dB

750Hz

0 dB

-

 

(reference)

 

15kHz

+17.0dB

± 1.8dB

9

TEST PROCEDURES

4.4Apply a 100Hz, 500mVrms signal to the input of the 802C.

4.5Reference a dB meter to the 302 AMP output jacks (while in the Bi-Ampmode).

4.6Refer to the frequency response table below and verify the response of the unit.

302 Bi-AmpFrequency Response Table

Frequency

Output

Tolerance

55Hz

+3.7dB

± 1.5dB

100Hz

0dB

-

 

(reference)

 

230Hz

-8.3dB

± 1.5dB

750Hz

-25.8dB

± 2.5dB

5. Distortion Test

Note: Total harmonic distortion must be measured in all modes to assure proper operation.

5.1Apply a 750Hz, 5Vrms signal to the input of the 802C.

5.2Refer to the table below for the distortion specification for the corresponding mode being tested.

Note: For theBi-Amp302 reading the input signal should be a 100Hz, 5Vrms signal.

Distortion Table

Output

Frequency.

Distortion

802 Full

750Hz

<0.1%

Range

 

 

302 Passive

750Hz

<0.1%

802 Bi-Amp

750Hz

<0.1%

302 Bi-Amp

100Hz

<0.1%

6.Noise Test

6.1All noise measurements are ANSI A-weightedtrue rms, with the inputs shorted.

6.2Refer to the table below for the proper noise levels.

Noise Table

Output

Noise

802 Full

<20uV

Range

 

302 Passive

<20uV

802 Bi-Amp

<20uV

302 Bi-Amp

<10uV

10