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--117aWL C-1
Better sound through research
Video RoomMate® POWERED SPEAKER SYSTEM
·
SPECIFICATIONS
Transducer: Frequency Response:
1, 41/2-inch full-range HVC driver 80 - 15 kHz
per enclosure Maximum SPL:
Enclosure: (1 meter on axis pink noise)
High-impact Polystyrene Copolymer 100 dB
Speaker Dimensions: Input Impedance:
9" W x 6" D x 6" H 10 k ohms
(22.9 W x 15.2 D x 15.2 H cm) (20 k ohms dc resistance)
Shipping Weight:
14 pounds per system
(6.35 kg)
©1986 Bose Corporation
!t5.00 Service Manual
Video RoomMate® INITIAL TEST PROCEDURE
NOTE: Since the Video RoomMate is a self-amp- 5. If the Video RoomMate system
lified loudspeaker system, it is best to begin initial A. Functions normally:
testing as per the normal operating instructions. In 1. Check the input cable for intermittent
this manner you will be able to verify that all con- operation.
nections are correct and if the original complaint 2. Check the power cord for intermittent
can be duplicated. operation.
3. Check volume control for intermittent
CONNECTION INSTRUCTIONS:
operation.
1. Connect the Video RoomMate's POWERED 4. Make sure the customer is using a stereo
enclosure's output terminals to the ACCESSORY source or a mono-to-stereo "Y" adaptor
enclosure's input terminals. Make certain that plug.
polarity is observed. (See Figure 1.)
B. Has no output from either enclosure:
1. Check resistance of the power cord (30 to
INITIAL CONNECTION PROCEDURES
100 ohms, depending on operating vol-
Striped Wire tage) for open line cord or power trans-
Red Terminal
former primary.
Black Wire
Black Terminal 2. Check input cable (tip to sleeve on both
plugs) for an open condition (normally 20
k ohms dc resistance).
3. Check volume control for proper
operation.
Powered
Speaker
Accessory
Speaker
4. Check the PCB for failure.
FIGURE 1
NOTE: The amplifier PCB for both channels is
located in the POWERED enclosure.
2. Connect the stereo RCA input plugs of the 5. Measure the impedance of each trans-
POWERED enclosure to the Audio Line Output ducer (approximately 1.5 ohms).
jacks of any receiver, tape deck, or other component
with Audio Line output capability. (See Figure 2.) C. Output from POWERED enclosure only:
1. Check the red input cable (tip to sleeve)
NOTE: The Video RoomMate is a stereo unit. The for open condition (normally 20 k ohms
ACCESSORY speaker will not function with a mono
dc resistance).
input unless a mono-to-stereo "Y" adaptor plug is 2. Check continuity of speaker wire con-
used. necting the two enclosures together.
3. Check impedance of ACCESSORY enclo-
sure's transducer by measuring at the
CONNECTION TO A SIGNAL SOURCE
input terminals (normally 1.5 ohms).
AUDIO OUT 3. Check volume control for proper
operation.
0 Right (0 )Left 4. Check the PCB for failure.
NOTE: The amplifier PCB for both channels is
Red Black located in the POWERED enclosure.
D. Output from ACCESSORY enclosure only:
Input TT 1. Check the black input cable (tip to sleeve)
Cable for open condition (normally 20 k ohms
FIGURE 2
dc resistance).
2. Check the PCB for failure.
3. Check impedance on POWERED en-
3. Connect the POWERED enclosure's power cord closure's transducer (normally 1.5 ohms).
into a variac or wall outlet.
NOTE: If lack of bass response is noted, check wir-
4. Adjust the volume control of the Video Room- ing with schematic diagram on page 7 to assure that
Mate to the desired operating level. the speakers are wired in phase.
2
Video RoomMate® IN-DEPTH TEST PROCEDURE
TRANSDUCER TESTING
1. RUB AND TICK TEST: Connect a sine wave
oscillator to the input cable of the Video Video RoomMate TEST CONNECTIONS
RoomMate. Connect the power cord to a
variac and set to the appropriate voltage. (See
Figure 3.) Adjust the frequency of the oscillator
to 10 Hz and the output to 100 mV. With the
Video RoomMate's volume control set to max-
imum, no extraneous noises such as rubbing,
scraping, or ticking should be heard.
NOTE: To distinguish between normal suspen-
sion noise and rubs or ticks, remove the grille
(see Grille Removal Procedure), and displace
the surround of the driver slightly with your
fingers. If the noise can be made to go away or
replace the driver. The whooshing noise from
get worse, it is a rub or tick, and the driver
the port at 80 Hz is normal.
should be replaced. If the noise stays the same,
it is suspension noise, and the driver is fine. NOTE: There should be no buzzes or rattles
Suspension noises will not be heard with pro- from within the Video RoomMate cabinet.
gram material. Redress any wire that buzzes.
2. SWEEP TEST: Sweep the oscillator from 10 Hz NOTE: If lack of bass response is noted, check
to 15 kHz. There should be no loud extraneous wiring with schematic diagram on page 7 to
sounds. If there are loud buzzes or distortion, assure that the speakers are wired in phase.
TRANSDUCER REPLACEMENT PROCEDURE
1. GRILLE REMOVAL: Align the driver and gasket to the J-clips. Make
To remove the grille, grasp the EDGE of the certain the gasket is correctly positioned behind
grille at one of the corners. GENTLY work the the driver to provide an airtight seal. Secure the
grille out of the retaining slot. driver to the J-clips with the three (3) screws
(see Figure 4). DO NOT overtighten.
NOTE: There is no grille frame exposed. You
MUST grasp the grille on the cloth portion of
the grille and NOT the polystyrene, which is DRIVER REPLACEMENT AND
J-CLIP ALIGNMENT
part of the speaker enclosure.
2. DRIVER REPLACEMENT:
Using a 1/4 "socket, remove the three (3) screws
holding the driver in place. Carefully lift the
driver out of the enclosure and cut the wires as
close to the driver terminals as possible. Strip
the wires and reconnect to the replacement
driver. Make certain that the red wire is con-
nected to the positive (+) terminal and the black
wire is connected to the negative (-) terminal of
the driver.
Video RoomMate® PRINTED CIRCUIT BOARD TEST PROCEDURE
SCOPE driver, remove the two (2) screws holding the
PCB in place. Once the screws have been
The Video RoomMate powered speaker sys- removed, pull the PCB straight out, releasing
tem has its built-in amplifier located in the the PCB from the retaining slots in the back of
POWERED enclosure. This test procedure cov- the enclosure.
ers the following areas:
1. Idle current 3. ADDING LOAD RESISTORS:
2. Frequency response Connect the first 2-ohm, 5-watt resistor to the
3. Distortion red and black terminals on the back of the
4. Compressor POWERED enclosure. This is the load for the
5. Separation ACCESSORY channel.
6. Noise ratio
7. Volume control NOTE: The amplifier outputs are 1800 out-of-
8. Output offset phase with each other. This is corrected in the
wiring from the PCB to the output for the
TEST EQUIPMENT REQUIRED
ACCESSORY speaker in the POWERED
1. Dual trace oscilliscope enclosure.
2. Audio signal generator
3. Distortion analyzer NOTE: The ACCESSORY amplifier's signal return
4. dB meter is NOT the black terminal. For test purposes,
5. Digital voltmeter you must use the red terminal as the signal
6. Two 2-ohm 5-watt load resistors return line to prevent damaging the amplifier.
Next, remove the black wire from the POWERED
enclosure's driver. Connect the second 2-ohm
TEST PREPARATION resistor between the black wire and the red
wire (still connected to the driver). NORMAL
1. BAFFLE REMOVAL (Powered Enclosure): polarity rules apply.
To properly test the Video RoomMate PCB,
TESTING
you must use two 2-ohm load resistors on the
amplifier outputs. To gain access to the ampli- 1. IDLE CURRENT:
fier PCB and the POWERED enclosure's output, Remove either of the red transformer secon-
you must remove the baffle. To remove the dary wires from the wire wrap terminal on the
baffle, remove the six (6) cross-recess drive PCB. Insert an ampmeter between the secon-
screws that holds the baffle in place. Do NOT dary and the wire wrap terminal.
remove the three (3) screws holding the driver
in place. OUTPUT:<300 mA
Once the screws are removed, pry the baffle 2. FREQUENCY RESPONSE:
away from the enclosure body. This can be With the volume control on the powered
easily accomplished by inserting the hOok por- enclosure set to the maximum position and the
tion of a scribe or your fingers into the ports. input cable connected to the signal source,
Use this as a grasping area to pry the two sec- adjust the input level to 50 mV at 1 kHz. Set the
tions apart. This will expose the transformer and dB meter to reference at the input signal.
PCB. Untwist the various service loops for
convenience. Move the dB meter to the output:
2. PRINTED CIRCUIT BOARD REMOVAL: OUTPUT: 300 mV per channel.
Using a 1/4" socket or angled flat- blade screw- (+ 15.9 dB ±1.8 dB from input)
Video RoomMate® PRINTED CIRCUIT BOARD TEST PROCEDURE (Continued)
THIS IS THE REFERENCE SIGNAL. Set your dB OUTPUT: 300 mV per channel
meter to reference and perform the following (+15.9 dB ± 1.8 dB from input)
response test: Move the volume control on the POWERED
TABLE 1 enclosure gradually to the minimum position.
FREQUENCY (Hz) RESPONSE (dB) OUTPUT: Will gradually reduce to 0 volts
1 kHz 0 - Reference BALANCE: ± 4 dB along complete range.
100 Hz +15.7 ± 1.8 dB 8. OUTPUT OFFSET:
10 kHz +15.9 ± 1.8 dB Set signal source to 0 volts. Using a digital volt-
meter, measure the dc voltage across the load
3. DISTORTION: resistors.
Keep the signal source at 50 mV at 10 kHz. OUTPUT: <50 mV per channel.
Measure the distortion at the output load resis-
tors of each channel. NORMALIZING THE SYSTEM
DISTORTION: <.25% on both channels. 1. REMOVING LOAD RESISTORS:
4. COMPRESSOR TEST: Disconnect the resistor from the back of the
POWERED enclosure. Also, remove the resistor
Return signal source to 1 kHz and increase the from the black and red wires of the POWERED
input signal to 500 mV. enclosure's driver. Reconnect the black wire to
Using the 500 mV input signal as reference, the driver.
measure the output signal.
2. PRINTED CIRCUIT BOARD INSTALLATION:
OUTPUT: 2.75 volts (+15.9 dB ± 1.8 dB)
Place the PCB onto the guide rails between the
Increase input signal 2 dB (620 mV) two baffle mounting posts. Push the board back
OUTPUT: 2.75 volts (+15.9 dB ± 1.8 dB) into the enclosure until the clips lock into
place. Do NOT pinch any wires.
5. SEPARATION TEST: Secure the front of the PCB with the two
Reduce the input signal to 400 mV at 1 kHz. screws, using a 1/4" socket or an angled flat-
Eliminate the signal from the right channel by blade screwdriver. Do not overtighten.
disconnecting the red input from the signal ,
Twist excess wire iinto service loops.
generator.
3. BAFFLE AND ENCLOSURE ASSEMBLY:
OUTPUT: 2.5 volts (+15.9 dB ± 1.8 dB),
To reassemble the enclosure and baffle, align
left channel
the port side of the baffle to the side of the
OUTPUT: <200 mV on the right channel
enclosure that has the input terminals. (The
Repeat the same procedure for the opposite baffle will fit correctly only one way.) Secure
channel. the baffle with the six (6) screws. Do NOT over-
tighten the screws.
6. NOISE RATIO:
4. GRILLE INSTALLATION:
Remove both input plugs from the signal source.
To install the grille, first make certain that the
OUTPUT: <100 uV, both channels. A weighted. logo position is correct (not upside down) with
the print on the back of the speaker enclosure.
7. VOLUME CONTROL:
Fit the grille to two adjacent corners of the
Reconnect both input plugs to the signal source. enclosure. Gently apply pressure to the two
Assure that the input signal is 50 mV. Measure remaining corners to fit the grille into the
the output. enclosure.
Video RoomMate® COMPONENT AND ETCH VIEWS
MAIN PCB
2P
--ft./711r5. TS?\
E
11,
C101
C103
.-1"
U '
Ln
·
<
LKh jLkLLfl R112
Itto e U2
--
(7=-
t
ic R101
C209
C3 (
e
54
C107
C109
0
FIGURE 5
Video RoomMate PARTS DRAWINGS PARTS LIST
· Screw, SM #8 x 5/8 L, Driver 108877
· J Clip, Driver 129504
0 Driver 123985-5
®
0 Driver Gasket 128407
0 Knob, Volume Control 127649
0 Nut, Volume Control 128429
®@ FRONT 128430
· Washer, Flat
VIEW
®To FIGURE 7 0 Screw, SH MET #8 x 3/4 L, Baffle 103126-12
0 Logo 128663
0 ® Nut, Push On 125786
CD Grille Assembly, (Powered) 127737
®0 · Grille Assembly, (Accessory) 127738
CD Threaded Insert 123991
(I) Stereo Input Cable 130709
BOTTOM ® Clip 128043
VIEW 128816
® Guillotine Connector
FIGURE 8
® Gasket, Guillotine 128666
® Screw, Bk, Cr Rec #6 x 1/2 L 124773-08
® Line Cord, 120V 125710
® Line Cord, 220V 125711
® Line Cord, 250V Aus 128932
® 124724
® Strain Relief
0 Closed End Splice 125618
® BACK
VIEW ® Switch, Line Voltage Selector (Military) 124854
FIGURE 9 ® Switch, Power (220, 240, 250 Volt) 130265
® Gasket 128409
® Terminal (220, 240, 250 Volt) 130412
® Screw, Bk, Cr Rec #6 x 5/8 L (220, 240, 250 Volt) 103122-10
® Speed Nut (220, 240, 250 Volt) 125571
Video RoomMate® SCHEMATIC DRAWING
HIGHEST REF. DES.
100-0, 110-V VERSION MILITARY VERSION COMPONENT COMMON ACCESSORY POWERED , NOT USED'
T T- 1 RESISTORS R5 8121 R221 R118
RD CAPACITORS C7 C110
1 C210
RD 115 TRANSISTORS Q1 Q101 Q201
DIODES 02 0102 0202
SI
00 OR
, L
IC'S, OP AMPS
RECTIFIER
04
81
YL
9 B N1 POTENTIOMETER VR1
0,
CONNECTOR P1
230
RD BL RD
P105 CIO R110
82.0 .0018
'\AA, 1
R103 ±004> RIO
VR I 18.2 k ,1%
20K 3GK
4i
) V+ A/V\i
C101 P102
1 V-t-
TAP IA 0101 18.214,1% C103 = C105 R108
.15 .1 24K R
P21 UIB 34
RI U2A /\/,
8 5.2K BI0G100K
II WV- 3
R101 C102. R112 V+
K 1 F
17p
R111
114,110
P1
lo
3°
2°
0 91
V+
R2040
± CI tOOK
D201 ILi
7:7
'VV\, R2
4 P204 C205 R207 31:
C201 K .1 24 K 6 U2 B · 'NA
1
TAP R202 2 UlA · MA/
0202
C202 R203 R208
47pF 18.2K,1% _C203 14K
AE R201 . 15
241K V- ,
v\A,,
R209
NOTES: C2O4> 3 (a 1·<,
R205 .00G8
1. UNLESS OTHERWISE SPECIFIED: 820
a ALL RESISTORS ARE 1/4W, 2%, AND EXPRESSED IN OHMS. 1
C20( R210
b. ALL CAPACITORS ARE EXPRESSED IN MICRO FARADS. .0018 24K
c. ONLY REPLACE: Ti WITH EXACT TYPE (BOSE P/N 128056 (120 VRMS),
P/N 128057 (220/240 VAC), P/N 128058 (115/230 VAC); AND LINE CORD WITH P/N 125710
(120 VAC, or P/N 125711 (220 VAC) AVAILABLE FROM:
BOSE CUSTOMER SERVICE
78 TURNPIKE RD.
WESTBORO, MA 01581
2. TO COMPLY WITH SAFETY STANDARDS, ALL ELECTRONIC PRODUCTS RETURNED FOR SERVICE MUST HAVE A
RESISTANCE MEASUREMENT TEST MADE BETWEEN THE LINE CORD (MAINS SUPPLY) CONTACTS AND THE
CHASSIS GROUND BEFORE RETURNING IT TO THE CUSTOMER. THE RESISTANCE MEASUREMENT IS TO MAKE
SURE A POSSIBLE SHOCK HAZARD DOES NOT EXIST. THE ENCLOSURE MUST BE FULLY ASSEMBLED FOR TEST-
ING. UNPLUG THE PRODUCT FROM THE WALL RECEPTACLE (MAINS) ANS MEASURE THE RESISTANCE
BETWEEN ONE OR BOTH OF THE TWO LINE CORD PLUG CONTACTS AND CHASSIS (GROUND), WHICH SHOULD
BE TEN MEGOHMS D.C. MINIMUM. IF NOT, CHECK FOR POSSIBLE SHORTS IN THE PRIMARY (MAINS) CIRCUITRY
AREA OF A FAULTY POWER TRANSFORMER.
7
NOT USED 220-0, 240-V VERSION I T2.
R118
C108
10OpF
R115
100K
R113 R I·41
30K 520 CIOS R 16, V+
5.1K 0
14 R11
12_ Wv
11 Ilk
5
V-- U3
R3 A BN 0 D ACCESS°R`f
I
100K SPEAKER
RI
1M5% OR
01 C110
1)2 1.2_2
A
DI
Rz1 G1,101
10K,5% o --4--R D
CS CG
-1700 -1700
?SI K )
R5 1 C2.
IM TbC)
5%
0201
_ R2I7
-1- C207
4. 22 C209 R21G V0 i
R21? R2 1.4 IQ 5.IK BK-
30K 52.0 U 2C · ) 14- WV- 0-- POWERED
7--·--4,---AAA,---· _,v \,,,,--.--
9 0 SPENcER
R2I5 RD +
100K Cz1
AAA/
i
C2.05
IC.)0 pF R2_I8 R2I9
5.1K IIK
RoomMate® AMPLIFIER/EQUALIZER PARTS LIST
SEMICONDUCTORS RESISTORS (Continued)
Location Description Part No. Location Description Part No. ,
U1 IC (RC 4559) 108568 R121, 221 Resistor, CF, 2.00K 1/4W 1% 119976-2212001
U2 IC (LS404) 120535 VR1* Potentiometer, 20K, 6-Pin 127727
U3, 4 IC (ULN 3751) 127067 VR-1* Potentiometer, 20K, 8-Pin 128861
Q1 Transistor - PNP (A 608) 119168
Q101, 201 Transistor - NPN (C536) 117921
VOLTAGE VARIANCES
D1, 2, 101, 102, Diode (IN4148) 121501 Strain Relief 124724
201, 202 Closed End Splice 125618
Z1 Bridge Rectifier (KBP 005) 124785 Line Cord, 120V 125710
Line Cord, 220V 125711
CAPACITORS Line Cord, 250V Aus 128932
Cl, 3, 4, 7 Capacitor, CER, .1 uF 117502 Transformer Screw, Hex Wshr. Face, #8 x 3/4 125916
C2 Capacitor, Elect. 10 uF 35V 119944-100 Mount
C5, 6 Capacitor, Elect. 4700 uF 16V 124997 Transformer, Power 120V 128056
C101, 201, 109, Capacitor, Elect., 1 uf 50V 119942-1RO Transformer, 220V 124397
209 Transformer, Power 230V 128057
C102, 202 Capacitor, Cermic 47 pF 5% 119617-470 Transformer, 115V/230V Military 128058
C103, 203 Capacitor, Film .15 uF 5% 118091-154
C104, 204 Capacitor, Film .0068 uf 5% 118091-682 MISCELLANEOUS
C105, 205 Capacitor, Film .1 uF 5% 118091-104 U3, 4 Heat Sink 129364
C106, 206 Capacitor, Film .0018 uF 5% 118091-182 P1 4 Pin Header 127740-04
C107, 207 Capacitor, Elect. 22 uF 35V 119944-220 Cable, 4 Conductor 128403
C108, 208 Capacitor, Elect .100 pF 5% 119617-101 Nut, Kep 4-40 100413-5
C110, 210 Capacitor, Film, .22 uF 122026-224 Screw, 4-40 1/4" Fil Head 103140-04
Screw, 4-40 x 5A6" Pan Head CR 103140-05
RESISTORS Bumper 103593
Location Description Part No. Interconnect Cable 123576
R1, 5 Resistor, CF, 1M 1/4W 5% 117704-1211055 Front PCB Screw, Hex Wshr. Face #6 x 3/8" 124721-06
R2 Resistor, CF, 91K 1/4W 2% 117704-1219132 Mount
R3, 106, 206, Resistor, CF, 100K 1/4W 2% 117704-1211042 Front PCB Tinnerman Nut 124617
115, 215 Mount
R4 Resistor, CF, 10K 1/4W 5% 117704-1211035 Rear PCB Tinnerman U Clip 124722
Mount
R101,201, 107, 207, Resistor, CF, 24K 1/4W 2% 117704-1212432
108, 208, 110, 210 . Sheild, PCB 128552
R102,202, 103, 203 Resistor, CF, 18.2K 1/4W 1% 119976-1211822 Cable, Adapter, Mono. 128596
R104,204 Resistor, CF, 8.2K 1/4W 2% 117704-1218222 Sheild, Metal RF 128740
R105,205, 114, 214 Resistor, CF, 820 1/4W 2% 117704-1218212 Nylon Spacer 128804
R109, 209 Resistor, CF, 36K 1/4W 2% 117704-1213632 Plastic Rivet 128805
R111,211 Resistor, CF, 1.00K 1/4W 1% 119976-2211001 Wire Clamp 128818
R112,212 Resistor, CF, 1.69K 1/4W 1% 119976-2211691 Foam Filler 124921
R113,213 Resistor, CF, 30K 1/4W 2% 117704-1213032 Corrugated Divider 125604
R116,216, 218 Resistor, CF, 5.1K 1/4W 2% 117704-1215122 Owner's Manual 127331
R117,217, 119, 219 Resistor, CF, 11K 1/4W 2% 117704-1211132 Carton 127335
R120, 220 Resistor, CF, 1 ohm 1/4 5% 117704-1211R05 Accessory/Literature Kit 127339
*NOTE: If replacement of VR-1 is necessary, refer to steps 1&2 of TEST PREPARATION (Baffle and PCB Removal).
8
SPECIFICATIONS AND FEATURES SUBJECT TO CHANGE WITHOUT NOTICE
REV. 12/86
Better sound through research.
Bose Corporation
The Mountain
Framingham, Massachusetts USA 01701
P/N 131022 FOR TECHNICAL INFORMATION ON PARTS ORDERING, CALL: 617-879-7330