Bose FREESPACE BUSINESS User manual

BOSE®FREESPACE®
SYSTEM CONTROLLER
©1995 Bose Corporation Service Manual
P/N 175031
®

2
TABLE OF CONTENTS
Electrostatic Discharge Sensitive (ESDS) ........................................................................ 2
Safety Information............................................................................................................... 3
Specifications......................................................................................................................4
Specifications......................................................................................................................5
Figure 1. Block Diagram ............................................................................................... 6
Figure 2. Input Connections.......................................................................................... 7
Figure 3. Output Connections....................................................................................... 7
Figure 4. Rear Panel View ............................................................................................ 7
Disassembly / Assembly procedures................................................................................ 8
Figure 5. Exploded View .............................................................................................10
Test Procedures ................................................................................................................ 11
Test Set-Up Parameters.................................................................................................... 11
Part List Notes................................................................................................................... 14
Main Assembly Parts List................................................................................................. 15
Figure 6. MainAssembly.............................................................................................15
Electrical Parts List...........................................................................................................16
Packaging ..........................................................................................................................21
Figure 7. Packaging....................................................................................................21
Main PCB Schematic ........................................................................................................22
REV 0/ REV1
Main PCB Schematic ........................................................................................................23
REV 0/ REV1
Main PCB Schematic ........................................................................................................24
REV 0/ REV1
Main PCB Schematic ........................................................................................................25
REV 0/ REV 1
I/O PCB Schematic............................................................................................................ 26
REV 1
I/O PCB Schematic............................................................................................................ 27
REV 1
I/O PCB Schematic............................................................................................................ 28
REV 1
I/O PCB Schematic............................................................................................................ 29
REV 1
I/O PCB Schematic............................................................................................................ 30
REV 0
I/O PCB Schematic............................................................................................................ 31
REV 0
I/O PCB Schematic............................................................................................................ 32
REV 0
I/O PCB Schematic............................................................................................................ 33
REV 0

3
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.
CAUTION: THE BOSE® FREESPACE®SYSTEM CONTROLLER
CONTAINS NO USER-SERVICEABLE PARTS. TO PREVENT
WARRANTY INFRACTIONS, REFER SERVICING TO WARRANTY
SERVICE STATIONS OR FACTORY SERVICE.
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.

4
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-With the unit completely reassembled, plug
theAC 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 forAppliances" and Underwriters Laboratories
(UL) 1492 (71). With the unitAC switch first in the ON position and then in
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 INDICATEA 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 poss-
ibility of a shock hazard, and the unit must be repaired and rechecked before it
is returned to the customer.

5
SPECIFICATIONS
Page Input
Channel A and B input
Balanced inputs with gain switches
Line Input Sensitivity at 300mV:
Line Input Sensitivity at 2V:
Line Input Impedance:
Outputs
All balanced outputs with protection diodes, and RFI/EMI noise suppression
(Measured with a 600Ωload.)
200mV nominal, 300mV maximum
1V nominal, 2V maximum
275µV minimum
5mV nominal, 250mV maximum
100mV nominal, 1V maximum
Page Trigger Sensitivity:
Mic Input Sensitivity:
Line Input Sensitivity:
Page Input Impedance:
Gain is switchable for either microphone or line level
1 5/8" H x 19" W x 10" D (4.13x48.26x25.4 cm)
5.5 lb (2.5 kg)
Dimensions:
Weight:
Line Output Level:
Line Output Frequency Response:
Line Output Impedance:
Line Output Paging:
Model 25, 32 or Bose®102®output level:
Model 25, 32 or Bose 102 output impedance:
Model 25, 32 or Bose 102 frequency
response:
Model 25, 32 or Bose 102 paging:
Model 8 Output Impedance:
6Vrms maximum
40Hz - 20KHz flat
600Ω, balanced
Channels A and B paging individually switchable
6Vrms maximum
600Ω, balanced
Flat power with Model 25 or 32 loudspeakers
Channel A - on
Channel B - switchable
600Ω, balanced
200 KΩ(MIC), 6.5KΩ(Line) balanced
100 KΩ(MIC), 3KΩ(Line) Unbalanced
4KΩ(2V), 14KΩ(300mV), Balanced
2KΩ(2V), 7KΩ(300mV), unbalanced

6
(Continued)
Outputs
(Continued)
Flat power response with Model 8 loudspeaker
Channel A - On
Channel B - Switchable
Model 8 Frequency Response:
Model 8 Paging:
Miscellaneous
Common Mode Rejection:
Opti-voice®System Circuitry:
Automatic Gain Control with LED Indication:
Power Requirements:
Determined by Selector Switch
Power Consumption:
40dB or greater
The system automatically switches from music
to page during paging.
Adjusts paging volume. LED flickers at optimum
volume.
100V, 120V, 220V - 240V ~ 50/60Hz
7 Watts
SPECIFICATIONS

General Description
The Bose® FreeSpace® system controller can be used with Bose busi-
ness music products. It features:
• Acti e equalization for the FreeSpace Model 8, Model
25, Model 32, and Bose 102® loudspeaker.
• Two channels of non-equalized line output, which can
be used to interconnect systems like the Bose FreeSpace
One and FreeSpace 6 business music systems.
• Three separate input channels for microphone, channel
A and Channel B.
• Opti- oice circuitry for paging capability.
• Rack-mount enclosure allows simple installation.
Figure 1. Block Diagram
7

Figure 4. Rear Panel View
Figure 3. Output Connections
Figure 2. nput Connections
8

9
DISASSEMBLY / ASSEMBLY PROCEDURES
6. Main PCB Replacement
6.1 Orient the Main PCB (1) so that LED 1
and 2 are lined up with the power and page
indicators on the front panel.
6.2 Line up the holes on the Main PCB
with the standoffs (14) on the chassis (2).
6.3 Apply downward pressure until the
Main PCB snaps onto the chassis's stand-
offs.
6.4 Install three screws (9) that secure the
Main PCB to the Chassis.
7. Transformer Removal
Note: Perform step 9 also. The trans-
former and the power connector are one
assembly.
7.1 Remove the four nuts (11) which
secure the transformer (15) to the chassis
(2) and one nut that secures the ground lug
to the chassis.
7.2 Desolder the primary wires from the
power connector (16) (make note of
wiring configuration).
7.3 Disconnect the secondary connector
(J5) from the Main PCB (1).
7.4 Lift the transformer up.
8. Transformer Replacement
Note: Perform step 10 also. The trans-
former and the power connector are one
assembly.
8.1 Orient the transformer's (15) secondary
wires (two yellow, one brown) towards the
front of the unit.
8.2 Align the four studs (17) with the four
holes in transformer bracket.
NOTE: Numbers in parentheses corre-
spond to figure 5.
1. Top Cover Removal
1.1 Remove two screws (10) from the rear
cover (3).
1.2 Remove two screws (8) from the top of
cover.
1.3 Slide cover towards the rear of chassis
and lift up.
2. Top Cover Replacement
2.1 Slide the top cover (3) onto the unit so
that the lip of the cover fits under the front
panel (4).
2.2 Install two screws (10) at the rear of
cover.
2.3 Install two screws (8) at the top of
cover.
3. I/O PCB Removal
3.1 Remove the six screws (9) that secure
the I/O PCB (13) to the chassis (2).
3.2 Disconnect the ribbon cable (12) by
pulling cable up at jack E1A (Main PCB).
4. I/O PCB Replacement
4.1 Orient I/O PCB (13) so that the
switches protrude out the rear of unit.
4.2 Install six screws (9) that secure the
I/O PCB to the chassis (2).
5. Main PCB Removal
5.1 Remove the three screws (9) which
secure the Main PCB (1) to the chassis (2).
5.2 Lift up the Main PCB with your hands
located by the two standoffs (14).
5.3 Disconnect connector J5 from Main
PCB.

10
8.3 Install four nuts (11) that secure the
transformer to chassis (2) and one that
secures the ground lug to chassis.
8.4 Solder the secondary wires to the
power connector.
9. Power Connector Removal
9.1 Remove the two screws (10) that
secure the power connector (16) to the
chassis (2).
9.2 Slide the power connector out of the
chassis's rear panel.
10. Power Connector Replacement
10.1 Slide the power connector (16) into
the chassis's rear panel.
10.2 Install two screws (10) that secure the
power connector to the chassis (2).
10.3 Solder wires from switch and trans-
former to power connector.
11. Power Switch Removal
11.1 Unplug the red wires from the power
switch (6).
11.2 Squeeze the fastener at the rear of
switch.
11.3 Push the power switch out of the front
panel (4).
12. Power Switch Replacement
12. 1 Orient the power switch (6) so the
switch's spades are down.
12.2 Push the power switch into the front
panel (4) until the switch snaps into place.
12.3 Reconnect the red wires to the power
switch.
13. Front Panel Removal
13.1 Remove four screws (8) which secure
the front panel (4) to chassis (2).
13.2 Slide the front panel forward.
14. Front Panel Replacement
14.1 Slide front panel (4) onto chassis so
that the lip fits over top cover and bottom.
14.2 Reinstall four screws (8) which secure
front panel to unit.

11
Figure 5. Exploded View
6
7
9
9
8
8
10
10
10
11
3
1
5
2
4
12 13
14
15
16
17
FRONT VIEW
OF CONNECTOR
120V
USE ONLY WITH
250V FUSE
SEE PAGE 11
FOR VOLTAGE SELECTION
AND FUSE REPLACEMENT
18
19

12
TEST PROCEDURES
Test Set-Up parameters
Switches
All switches shall be set to their right
hand position. (Looking at the back of
unit)
Potentiometer
Page level should be fully clockwise.
Input Connections
Connect the positive (+) side of an oscilla-
tor to the positive input terminals. Connect
the negative (-) side to the negative (-) and
common input terminals. Do this for Chan-
nels A, B and Page, using the quick con-
nectors supplied in connector kit 180095..
Output Connections
Connect the positive (+) side of test equip-
ment to the positive (+) output terminals.
Connect the negative (-) side to the nega-
tive (-) and common output terminals.Do
this for channel A and B using the quick
connectors supplied in connector kit
180095.
All test equipment should be balanced or
isolated from ground (floated).
Voltage Selection/ Fuse Location
Using a screw driver, remove the voltage
switch located under the AC plug. Slide the
card out from the assembly, rotate and
reinsert. Selected voltage will appear in
window. The fuse is located in the card.
See parts list note three.
1. Output level
1.1 Apply a 2 Vrms, 1 KHz signal to
Channel Aand B input.
1.2 Reference a dB meter to the applied
signal.
1.3 Measure the output level according to
the chart below.
2. Frequency Response
2.1 Apply a 2Vrms, 1 KHz signal to chan-
nel A and B input.
2.2 Reference a dB meter to the output A
or B.
2.3 Measure the output level according to
the chart below.
Freq Min Max Unit Output
1 KHz 0 0 Ref
50 Hz +0.2 dBr line
15 KHz +0.2 dBr
1 KHz 0 0 Ref
50 Hz +3.0 dBr
90 Hz +11.0 +13.0 dBr Model 32
4 KHz +6.2 +8.2 dBr
12 KHz 14.0 +16.0 dBr
15 KHz +16.0 dBr
1KHz 0 0 Ref
50 Hz -10.5 dBr
100 Hz +10.0 +12.0 dBr Model 8
4 KHz +5.8 +7.8 dBr
10 KHz +11.3 +13.3 dBr
15 KHz +9.7 dBr
Output Min Max Unit
Line -5.3 -3.3 dBr
Model 32 -17.5 -15.5 dBr
Model 8 -18.9 -16.9 dBr

13
3. Distortion
3.1 Apply a 2Vrms 1 KHz, 90 Hz, and 100
Hz signal to Channel A and B input.
3.2 Measure the THD+N at the Line
(1KHz), Model 32 (90Hz), and Model 8
(100 Hz) outputs (≤.1 % THD+N).
4. Headroom
4.1 Apply a 7Vrms, 1 KHz, 90 Hz, and 100
Hz signal to Channel A and B input.
4.2 Measure the THD+N at theLine
(1KHz), Model 32 (90Hz), and Model 8
(100 Hz) outputs (≤2.5 % THD+N).
5. Noise
5.1 Short the positive (+) and negative (-)
inputs of ChannelA and B.
5.2 Measure the voltage at the Line, Model
32, and Model 8 outputs (≤75µV).
6. Common Mode Rejection
6.1 Connect the positive (+) side of a
signal generator to the positive (+) and
negative (-) inputs of Channel A and B.
Connect the (-) side of the signal generator
to signal ground.
6.2 Apply a 2Vrms, 1 KHz signal to Chan-
nelA and B inputs.
6.3 Reference a dB meter to the input
signal.
6.4 Measure Channel Aand B Line outputs
(≤-40dB).
7. Channel Separation
7.1 Apply a 2Vrms, 1 KHz signal to Chan-
nelA.
7.2 Reference a dB meter to Channel A
output.
7.3 Measure the output of channel B with a
dB meter (≤-50 dB).
7.4 Repeat this procedure for Model 32
and Model 8 outputs.
Note: Repeat this procedure for Channel
B.
8. Offset Voltage
8.1 Connect a DC meter to the Line, Model
32 and Model 8 output.
8.2 DC offset should be ≥-50 mV and ≤50
mV.
9. Page Inputs
9.1 Apply a 275µVrms, 400Hz signal to the
page input.
9.2 Insure that the page LEDs on the front
panel illuminates.
Note: See schematic (page 22) for Page
Triggering level modification.
10. Page Gain
10.1 Apply a 3mVrms, 1 KHz signal to
page input.
10.2 Reference a dB meter to the applied
signal.
10.3 Using a dB meter, measure outputs
according to the chart below for both
channels.
Output Min Max Unit
Line 48.2 50.2 dBr
Model 32 40.5 42.5 dBr
Model 8 39.0 41.0 dBr

14
14. Page Automatic Level Control
14.1 Apply a 1 KHz, 100mV signal to the
page input.
14.2 Reference a dB meter to the applied
signal.
14.3 Measure the Line output ( should be
≥19.7 dB and ≤21.7 dB ).
11. Page Mute
11.1 Apply a 3mVrms, 1 KHz signal to the
page input.
11.2 Apply a 2Vrms, 1 KHz signal to
channel Aand B input.
11.3 Remove the applied signal from the
page input ( page will mute audio for 3
seconds ).
11.4 Using the chart below, measure the
output of each channel.
Output Min Max Unit
Line 48 72 mV
Model 32 11 18 m v
Model 8 10 17 mV
12. Page Frequency Response
12.1 Apply a 1 KHz, 10mVrms signal to the
page input.
12.2 Reference a dB meter to Line Aor B
output.
12.3 Using the chart below, check the
frequency response.
Freq Min Max Unit
1 KHz 0 0 Ref
400 Hz -2.8 -0.8 dBr
2KHz 0.6 2.6 dBr
5KHz 4.7 6.7 dBr
10 KHz -2.8 -0.8 dBr
13. Page Distortion
13.1 Apply a 1 KHz, 30mV signal to the
page input.
13.2 Measure THD+N at the Line output
( should be ≤3.0 %).

15
PART LIST NOTES
1. This part is not normally available from Customer Service. Approval from the Field Service
Manager is required before ordering.
2. The individual parts located on the PCB are listed in the parts list.
3. This part is critical for safety purposes. Failure to use a substitute replacement with
the same safety characteristics as the recommended replacement part might create shock, fire
and/ or other hazards.

16
Figure 6. Main Assembly
Item
Number Description Part Number Qty- Per
Assembly
See
Note
1 PCB Assy,8/32 Controler 179089 1 1, 2
2 Chassis,8/32 Controller 172262 1 1
3 Cover,8/32 Controller 172263 1
4 Panel,Front Chassis 172264 1
5Transformer,120/240V 173681 1 3
6Switch,Rocker,SPST,Power,PS1 143960 1 3
7 Lens,Led,Chassis,Clear 144023 2
8 Screw,Tapp,#4-40x.312,Btn,Xrec 170285-05 1
9 Screw,4-40x.25,Phil,Pan Hd 103140-04 9
10 Screw,Tapp,#4-40x.375,Pan,Xrec 170284-06 4
11 Stnd. Hex Nut,Washer,Keps 118260-08 5
18 Insulator,Chassis,8/32 Cntrlr 176146 1 1, 3
19 Fuse, Slow Blow, 315mA T, 250V 132645 1 3
!
!
!
!
Main Assembly Parts List
6
7
9
9
8
8
10
10
10
11
3
1
5
2
4
12 13
14
15
16
17
FRONT VIEW
OF CONNECTOR
120V
USE ONLY WITH
250V FUSE
SEE PAGE 11
FOR VOLTAGE SELECTION
AND FUSE REPLACEMENT
18
19

17
Reference
Designator Description Part Number See Note
R100, 101, 103,
105, 110, 111,
113, 115, 212,
345, 346, 445,
446
1.00k ,1%,Chip 133625-1001
R102, 104,
112, 114, 320,
335, 420, 435
5.76k,1%,Chip 133625-5761
R120, 121, 123,
125 1.69k,1%,1/10w 133625-1691
R122, 124, 215,
326, 426 100k, 1%,Chip 133625-1003
R128, 223, 226 1.0k,5%,1/2w,Cf 121243-1511025
R130, 132, 140,
142, 150, 152 249Ω,1/10w,1%, Chip 133625-2490
R131, 133, 141,
143, 151, 153,
308, 408
301Ω,1%,1/10w,
Chip 133625-3010
R154, 204, 237,
302, 317, 332,
402, 417, 432
301k ,1%,1/10w 133625-3013
R200, 300, 314,
315, 340, 341,
400, 414, 415,
440, 441
2.21k ,1/10w,
1%,Chip 133625-2211
R201 560Ω,5%,1/4w,Cf 121243-1215615
R202, 205, 233,
234 681Ω,1%,1/10w, Chip 133625-6810
R203, 222 306,
406 15.0k,1%,Chip 133625-1502
R206, 208, 213,
218, 220, 221,
225, 238, 239,
301, 304, 305,
309, 316, 319,
322, 323, 334,
336, 343, 401,
404, 405, 409,
416, 419, 422,
423, 431, 434,
436, 443
10.0k,1%,Chip 133625-1002
R207, 214, 217,
219, 229, 327,
427
33.2k ,1%,
1/10w,Chip 133625-3322
R209 8.25k ,1%,
1/10w,Chip 133625-8251
ELECTRICAL PARTS LIST
Resistors

18
Reference
Designator Description Part Number Note
R210 18.2k,1%,Chip 133625-1822
R211, 342, 442 2.67k ,1%,1/10w 133625-2671
R216, 329, 429 3.83k ,Chip,1% 133625-3831
R224, 227 150k ,1%,Chip 133625-1503
R228, 232 56.2k,Chip,1% 133625-5622
R230 330 Ω,
5%,1/4w,Cf 121243-1213315
R231, 312, 313,
324, 325, 330,
337, 339, 412,
413, 424, 425,
430, 437, 439
4.75K,1%,Chip 133625-4751
R235, 321, 421 22.1k ,1%,
Chip,Film 133625-2212
R303, 307, 318,
328, 333, 344,
403, 407, 418,
428, 433, 444
52.3 Ω,1%,1/10w 133625-52R3
R310, 311, 338,
410, 411, 438 121k ,1%,Chip 133625-1213
VR101 Pot,5k 172928-502
Reference
Designator Description Part Number Note
C100, 101, 110,
111, 120, 121,
126
33pf,50v,5% 133622-330
C102, 103, 112,
113, 122, 123
201, 205, 206,
215, 216, 226,
227, 232, 233,
300, 309, 316,
326, 327, 400,
409, 416
4.7uf,El,20% 137126-4R7
C104, 105, 114,
115, 124, 125,
127, 130, 133,
140, 143, 150,
153, 162, 163,
241
1000pf,50v,10% 133623-102
Resistors (continued)
Capacitors

19
Reference
Designator Description Part Number Note
C106, 116, 204,
303, 403 100pf,50v,5% 133622-101
C128, 129, 219,
221, 237, 238 10uf,0805,25v, 80% 133624
C156, 157, 158,
159, 164, 213,
214, 228, 229,
234, 235, 321,
322
.01uf,50v,10% 133623-103
C200, 217, 230,
231, 239 47uf,El,50v,20% 149948-470H
C202, 203, 240 100uf,El,20% 120767
C207 .022uf,Box,100v,
5% 137127-223
C208, 315, 415 .068uf,Box,63v,
5% 137127-683
C209 .0022uf,Box,100v,
5% 137127-222
C210, 319, 419 .0047uf,Box,100v,
5% 137127-472
C211 .0039uf ,
Box,100v,5% 137127-392
C212 .1uf ,Box,50v,5% 137127-104
C224 470uf,El,50v,20% 149948-471H
C225 .470uf ,
El,20%,50v 149948-471H
C305, 405 .056uf,Box,63v,
5% 137127-563
C306, 314, 317,
318, 324, 325,
406, 414, 417,
418, 424, 425
.047uf ,
Box,63v,5% 137127-473
C307, 407 .01uf ,
Box,100v,5% 137127-103
C308, 408 560pf ,50v,5% 140564-561
C310, 311, 410,
411 .0056uf,Box,100v, 5% 137127-562
C320, 420 820pf ,50v,5% 140564-821
C323, 423 .0068uf,Box,100v,
5% 137127-682
Capacitors (continued)

20
Reference
Designator Description Part Number Note
D100, 101 1n4746,Zen,18v,
1w,5% 116995-4746A
D2, 3, 5, 6 1n4148 121501
D4 Rectifier,Bridge,
100v,1a 143952 3
D7 Surge Absorber,
D Type 178096 3
DD1, 100, 101,
102, 103, 104,
105, 106, 107,
108, 109, 110,
111
Bav99,Sot23 147239
LED1 Led,Green,Right
Angle Mount 144027
LED2 Led,Amber,
Horzontal Mount
Pcb
172925
LED3 Led,Amber,
Vertical PCB 172924
Reference
Designator Description Part Number Note
Q1, 7 To-92, Bplr,
N,30v,500ma, 173476
Q2, 8, 9, 10, 11,
12, 13 JFET, N Channel 129363
Q3, 4, 14 NPN 117921
Q5, 6 PNP 119168
Reference
Designator Description Part Number Note
U1, 6, 7, 8 IC,Op Amp,Quad 144008
U2 Voltage
Regulator,+15v 144656
U5 Rc4559,Ic,Op
Amp,Dual,Dip-8 108568
U3 Voltage
Regulator,-15v 144655
U4 La3220 ,
Ic,Lin,Ml,Pos,14v
173478
!
!
Diodes
Transistors
Integrated Circuits