Shure SR110, SRI 10-2E User Guide

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60204 U.S.A.

COMPONENTS

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MODEL SR110 A)

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SRI 10-2E

PROFESSIONAL

MONITOR MIXERS

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OPERATION AND

DESCRIPTION

The Shure Model SR110 Professional Monitor Mixer

is a rack-mounted, eight-channel, line level mixer, de­signed as an accessory for the Shure Model
Series 2 Audio Console or SR109 Professional Mixer.

It can also be used with similar equipment when a
separate stage monitor mixer is desired to be added
to a sound reinforcement system. The

be used in multi-track recording applications as a re-

cording mix panel or in stereo broadcasting.

Interconnections between the
or SR109 are made through a single multi-pin con­nector and cable permanently attached to the SRllO.

SR110 also contains a matching female multi-pin

The

connector for "stacking" additional

The SR110 provides eight high-impedance, unbal­anced, line level inputs to its mixing circuitry, and one
high-impedance, unbalanced line level input to its
output selector switch for monitoring program mate­rial. The output of the
line level with one three-pin male professional audio
connector and two standard

phone jacks, connected in parallel.

The front panel of the SRllO contains eight rotary
volume controls for channel gain, and a combination

rotary master volume controllpower-off switch. An

output selector slide switch, headphones jack and

neon power indicator lamp are provided. Silicon
transistors and other solid-state devices are used
throughout. All components are of the highest quality,
and are operated well within their respective ratings
to assure maximum reliability under normal use con-

ditions.

SR110 and SR110-2E are identical except that

The

the SRllO operates from 108-132 Vac, 50160 Hz, and

SRllO-2E operates from either 105-125 or 210-250

the

Vac, 50160 Hz (switch-selectable).

SR110 Mixers are supplied with four rack-mounting
screws for mounting in standard 19 in. (483 mm) audio
equipment racks or in an optional Shure
ing Case (mounted with an

SR110-2E is supplied with a detachable ac line cord
(without power plug). The
Underwriters' Laboratories, Inc., and is listed by

Canadian Standards Association as certified.

SR110 is a 600-ohm balanced

SR109). In addition, the

SRl10 (only) is listed by

SR110 can also

SR110 and the SRlO1

SRllOs.

'/4

inch three-circuit

SRlO1

A105A Carry-

SPECIFICATIONS

.

Type

Copyright 1979, Shure Brothers Inc
27A1291

. . . . . . . . .

(56)

. .

.

.All silicon transistor monitor

mixer

SERVICE MANUAL

Number of lnput

Channels
Power Output
Voltage Gain*

Mixed

Inputs**

Program

Input**

Frequency

Response

lnput Sensitivity

Distortion

Noise

(300 HZ-20

Mixed

Inputs**

Program

Input**

Hum and Noise

(20 Hz-20 kHz)

Mixed

Inputs**

Program

Input**

lnput Clipping

Level at

lnput Impedance

at 1 kHz:

Mixed

Inputs**

Program

Input**

*Measurement conditions: Inputs through

terminated in

and channel Volume full up.

**OUTPUT SELECTOR

+MIX

BUS

. . . . . . .

. . . . .

. . .

. . . . . .

. . .

. .

. . . . .

kHz)

.

. . .

. . . . . . .

.

. . .

1 kHz

. . . . . .

. . . .

600

terminated

.8 mixed inputs; 1 program input

.

. . .

.38 i2.5 dB (LINE LEVEL Output)

.

.40 +-2 dB (LINE LEVEL Output)

.

.21

.

. .

.THD less than 1 % at + 12 dBm,

.

.

.

.

. . . . .

. . . . .

. .

.

. . . .

. . .

.2.5V min. on mixed inputs 1-8

. . .

ohms,

PHONES

Switch position.

in

5.6k.

+19.2 dBm (LINE LEVEL Output)

t2.5 dB (PHONES Output)

14.5

-8

+-2

dB (MIX BUS)t

i3 dB, 20 Hz-20 kHz (LINE

LEVEL Output)

mV max. for +4 dBm line

level output

30 Hz-20 kHz; IM distortion
less than 1 % at +12 dBm

-

68 dBV max. (MASTER
Volume Control down)

-54 dBV max. (MASTER and
channel Volume Controls up)

-58 dBV max. (MASTER
Volume Control up)

-

64 dBV max. (MASTER
Volume Control down)

-50 dBV max. (MASTER and
channel Volume Controls up)

-54 dBV max.

Volume Control up)

with channel Volume Controls
set at max. (input clipping
level increases with decreased
setting of channel Volume

Control)

kilohms

.23.5

kilohms

.30

output terminated in 8 ohms,

(MASTER

150

ohms, LINE LEVEL output

Printed in

MASTER

U.S.A.

FIGURE A. SR110 FRONT PANEL

Output Impedances: 3. MASTER Volume Rotary Control/POWER OFF

.

. . . .

Line Level
Headphone

. . .

. . . .

. .

. . .

. . . . .

. . . . . .

. . . . . .

.

Mix Bus

Phasing

Controls

Operating Voltage

Power

Consumption

Temperature:

Operating
Storage

Dimensions

Weight
Finish

Installation

Certifications . . . . . . .Listed by Underwriters' Labora-

OPERATING

Functional Description

1. Individual Channel Volume Rotary Controls (Eight) 1. Using hardware provided, install

-Control volume of each channel separately.

2.

Power-On Indicator Lamp-Indicates ac power is Carrying Case (with SR109) prior to making
being applied to unit. electrical connections.

..Balanced 120 ohms actual (for Switch-Adjusts level of total monitor output and

use with 600-ohm lines)

. . . .

.

.12 ohms actual (for use with 4-

to 16-ohm headphones)

.

.

.5.6 kilohms 5. OUTPUT SELECTOR Slide Switch-Selects be-

.

. . . . . . .Pins 1 through 8 of ACCESSORY

connector are out of phase
with,

and

pin 9

with, pin 3 of

&pin connector, tips of

put
LINE LEVEL and PHONES recording equipment.

jacks,

phono pin jack

and

is

in phase

LlNE LEVEL out-

tip

of

MIX

BUS

. . . . . . .Channel Volume: rotary, linear

taper; MASTER Volume:
rotary, audio taper

. . .

SR110: 108-132 Vac, 50/60 Hz.
SR110-2E:

Vac, 50/60 Hz.

. . . .

.3 watts max. (Mixer only)

500

ac receptacle)

. . .

. .

. . . -7" to 54°C (+20° to 130°F) 11. Ac Grounded Line Cord-Connects ac power

. . . -29" to 71°C (-20" to 160°F)

105-1 25 or 21 0-250

watts

max. (non-switched

(SR110 only)

applies ac power to power supply.

4.

PHONES Output Jack-Provides for connection of
stereo or monophonic headphones for monitoring.

tween signal mixed in SRllO (MIXED INPUTS) or
mixed in

6. MONITOR OUTPUTS/LINE LEVEL Three-Circuit
Phone Jacks (Two)-Provide balanced Monitor

Mixer output connection to power amplifier or

7. MONITOR OUTPUTS/LINE LEVEL 3-Pin Male

Connector-Provides balanced Monitor Mixer out­put connection to power amplifier or recording

equipment.

8. ACCESSORY INPUT AND OUTPUT Cable
Pin Male Connector-Provides for input connec­tions from Shure

ment.

9. ACCESSORY INPUT AND OUTPUT Multi-Pin
male Connector-Provides for connection of
tional parallel-wired (tandem)

10. MIX BUS Phono Jack-Provides common mix bus
when two
to be operated in a common mix mode.

source to

SRlO1 or SR109 (PROGRAM INPUT).

SRlOls or SRlO9s and two SRllOs are

SR110 power supply (SRllO only).

. . . . . . . .44.4 mm height X 483 mm 12. Non-Switched Ac Grounded Receptacle-Provides

width X 232 mm depth (1
X 19 in. X 9% in.)

. . . . .

.

. .

. . . . .

. . . .

. . . .Equipped for standard 19 in.

kg (8 Ib, 8 oz)

. .3.9

black

Matte

(483 mm) audio rack mount-

may be operated in

ing;

optional-~105~' Carrying Case

SR109)

(with

tories,
Standards Association as
certified (SR110 only)

Inc.; listed by Canadian

INSTRUCTIONS

(Refer to Figures A and B)

3/4

in.

up to 500 watts of non-switched ac power to
cessory equipment

13. AC (MAINS) POWER 3-Pin Connector-Connects

unit to ac (mains) power source via supplied line
cord

(SR110-2E only).

14. VOLTAGE SELECTOR Slide Switch-Selects 105-

125V or 210-250V input power

General Operating Instructions

WARNING

To reduce the risk of fire or electric shock,
do not expose this appliance to rain or ex­treme moisture.

in standard 19 in. (483

4

&

Multi-

SR101 or SR109 or similar equip-

Fe-

SRll 0s.

(SR110 only).

(SR110-2E only).

SR110 securely

mm) rack or optional A105A

addi-

ac-

-

AC

IMAINS!

POWER

*'c,,X?,I

-0.'

.*O

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OL'?.,

.dl

1,1*

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,,

2

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13

SR110-2E

ONLY

\

14

FIGURE

B.

SR110 REAR PANEL

?..Ll.i..

2.

Connect SR110 MONITOR OUTPUTS/LINE LEVEL

6)

3-pin connector and/or phone jacks (7,

to

power amplifier and/or recording equipment.

3. Connect
PUT Multi-Pin Male Connector

SR110 ACCESSORY INPUT AND OUT-

(8)

to SRlOl or

SR109.

4. If additional SRllO is to be used (tandem opera­tion), connect ACCESSORY INPUT AND OUTPUT
Multi-Pin Male Connector (8) of second

SR110 to
ACCESSORY INPUT AND OUTPUT Female Con­nector (9) of first

SR110.

5. If common mix between two SRlOls or SRlO9s
and two SRllOs is desired, interconnect MIX BUS
Phono Jacks (10) of each SR110 and interconnect
the link output jacks of the SRlOls or

SRlO9s.

6. (SRl10-2E only) Move VOLTAGE SELECTOR
Switch (14) to 115V or 220V position as required.

7.

Connect ac line cord to grounded 108- to 132-volt
(SRl1 O), or 105-1 25V or 21 0-250V (SR110-2E),
50/60

Hz

ac source.

8. Turn on front-panel POWER OFF Switch on
MASTER Volume Control (3). Red indicator lamp
(2) will light, indicating power is being applied.

9. Adjust

SRlO1 or SR109 and associated power

amplifier for desired operating levels.

10. Adjust SRllO and associated power amplifier
and/or recording equipment for desired operating
levels.

11. Set OUTPUT SELECTOR Switch (5) to MIXED IN­PUTS or PROGRAM INPUT as desired.

Mounting and Ventilation

SRl10 Professional Monitor Mixer is designed

The
for rack-mounting in a standard 19 in. (483 mm) audio
equipment cabinet rack and is supplied with the nec­essary mounting hardware (see Figure C). If possible,

SR110 should be rack-mounted above its as-

the
sociated

SRl 01 or SR109.

The SR110 may also be operated while mounted in

a Shure

A105A Carrying Case. The A105A will accept

panel heights of 7 in. (178 mm), providing space for

SRl10 and one SR109 Professional Mixer.

one

44.4

mm

(1-3/4 IN)

FIGURE

C.

OVERALL DIMENSIONS

No special precautions are required for ventilation.

The

SRl10 may be operated over a temperature range

-7" to 54°C (20" to 130°F) in continuous duty with-

of
out derating.

Power Supply

The

SR110 Professional Monitor Mixer is furnished
with a three-conductor power cable and three-prong
grounded plug (11). Connect the
which supplies 108 to 132 volts ac, 50/60

SR110 to an outlet

Hz

power.
The nominal power consumption at 120 volts under
normal operating conditions is 3 watts maximum (0.025
amperes at 120 volts). If extension cords are required
to supply power to the

SR110, a high-quality, 18-gauge

or larger cord should be used.

The

SRl10-2E is furnished with a three-conductor
line cord without a power plug. Obtain a suitable three­pin male power plug and attach it to the line cord. The
plug should be installed by qualified service personnel.

(Brown lead goes to "hot" or "live" terminal, blue lead

to neutral terminal, and

green/yellow lead to ground
or earth terminal.) Select proper operating voltage
(115V for 105-125V supply or 220V for 210-250V sup­ply) using the VOLTAGE SELECTOR Switch (14).

A POWER-OFF Switch located on the front-panel
MASTER Volume Control (3) controls the application
of ac power to the

SRl10, and a red indicator lamp

(2) indicates the power-on condition.
Functional Circuit Description

The inputs to the SRllO Professional Monitor Mixer
enter through the 11-pin

the cable (8) (see Figure D). The 11-pin female

male connector located on

con-

INPUT

AND OUTPUT

\

-----C-

/

CHANNEL

i

VOLUME -MIX

/

/'

I

DB

2

DB

MIX

RESISTOR

-

MASTER
VOLUME

CONTROL

-1

DB

OUTPUT

TRANSFORMER

-24

08

HEADPHONES
TRANSFORMER

f

=

-

FIGURE D.

SR110 BLOCK DIAGRAM

nector (9) is wired in parallel, and provides connection
for additional (tandem) SRllOs.

With the OUTPUT SELECTOR Switch (5) in the
MIXED INPUTS position, the input signals from the
individual channels of the
the individual channel Volume Controls
mixing amplifier, a -2 dB mixing resistor, and the
OUTPUT SELECTOR Switch before reaching the MAS­TER Volume Control
Switch in the PROGRAM INPUT position, the program
input signal from the
through the OUTPUT SELECTOR Switch to the MAS­TER Volume Control. The MIX BUS Jack (10) is con­nected after the mixing resistor and before the OUT­PUT SELECTOR Switch. The MIX BUS Jack is for
parallel operation of two or more
SRIIO

enters a +42 dB amplifier stage. The amplifier output
(-24 dB) output transformers. The line level trans-

former feeds a three-pin professional male audio con­nector
phone jacks (6). The headphone transformer feeds a
standard
designed for use with 8 ohm stereo or monophonic
headphones.

Inputs and Outputs
PUT AND OUTPUT 11-pin male connector (8). Pins 1

through 8 are the individual channel signals derived
from the eight
equalizer circuits), pin 9 is a total program signal
(taken from the
or

nected to the
male connector (9) is wired in parallel with the male

connector, and provides for connection of additional

(tandem)

consists of one three-pin professional male audio con­nector
phone jacks (6). These connectors provide three line
level, 600-ohm, balanced outputs to power amplifiers
or recording equipment.

connection when two SRlOls or
more SRllOs are to be operated in a common mix
mode (16 channels). If more than two SRllOs are used
"Y" adapters can be used to connect the additional
MIX BUS Jacks.

circuit (stereo) phone jack designed for use with
8-ohm stereo or monophonic headphones.

Stage Monitor

junction with the
CESSORY INPUT AND OUTPUT male connector (8) to
the
female connector (see Figure
channel Volume Controls (1) to be monitored on stage;
turn the remaining channel Volume Controls to
With the OUTPUT SELECTOR Switch in the MIXED IN-

combinations, providing 16 inputs with the OUT-

PUT SELECTOR Switch in the MIXED INPUTS position.

From the MASTER Volume Control

is fed to both line level (-1 dB) and headphone

(7)

and two standard

Y4

in. three-circuit (stereo) phone jack (4)

SR110 inputs enter through the ACCESSORY IN-

All

SR101 or SR109 channels (following the

SRlOl Monitor post link-pre link Switch

SR109 link input jack), pin 10 is the SR101 or SR109

+30 Vdc supply voltage and is not internally con-

SR110 supply, and pin 11 is ground.

The ACCESSORY INPUT AND OUTPUT 11-pin fe-

SRll 0s.

The MONITOR OUTPUTSILINE LEVEL connectors

(7)

and two standard

The MIX BUS Phono Jack (10) provides a common

The PHONES Jack

To use the

SRlO1 or SR109 ACCESSORY OUTPUTIAUX LEVEL

SR110 as a stage monitor mixer (in con-

SR101

SR101 or SR109 go through

(3).

With the OUTPUT SELECTOR

SR101 or SR109 goes directly

1/4"

three-circuit (stereo)

VI

in. three-circuit (stereo)

(4)

is a standard

or SR109), connect the AC-

E).

Turn up the individual

(I), a -1 dB

SR101 or SR1091

(3),

the signal

SRIO9s and two or

1/4

in. three-

0 (off).

TO

SRlOl CONSOLE

I

SR109

STAGE MONITOR CONNECTIONS

PUTS position and the MONITOR OUTPUTS connected
to the stage monitor power amplifier input, a separate
mix of inputs can be provided for stage monitoring.

SRI10 monitors the SR101 or SR109 individual

The
channels after the
tenuator, volume and equalizer controls.

With the OUTPUT SELECTOR Switch in the PRO-

GRAM INPUT position the stage monitor has the same

mix as the

SR101 or Sf3109 are used for the "house" PA system.
Broadcast Line, House PA and Stage Monitor

If the
cast line for radio or TV audio, and separate house PA
and stage monitor systems are required, a number of
SRllOs may be connected as shown in Figure F. The
program output of the
broadcast line, the monitor output of the first
feeds a stage monitor power amplifier, and the monitor
output of the second (parallel-wired)
house system power amplifier. Note that since the
ACCESSORY INPUT AND OUTPUT Connectors (8, 9)
of the
be parallel-connected.

The individual channels that are not to be fed to the
stage monitor or house PA can be left off by turning
their Volume Controls (1) to

Stereo or Multi-Channel Tape Recording

A set-up similar to that described under Broadcast
Line
stereo broadcasting. The monitor output from one
SR110 is connected to one input of the tape recorder
and the other
permits the user to select the desired mix on each
recording channel. For recording on more than two
channels, additional SRllOs can be added as desired.

16-Channel Mixer

For applications requiring the use of more than eight

channels, two SRlOls or
channel mixing system by connecting their LINK OUT­PUT Jacks. Monitoring of all 16 channels can be ac­complished by connecting two SRllOs to the SRlOls
or

SRlO9s as shown in Figure

SRlO1 or SR109. The program outputs of the

SR101 or SR109 is to be used to feed a broad-

SR110 are in parallel, up to eight SRllOs may

above can be used to record a stereo tape or for

BROADCAST LINE CONNECTIONS

ACCESSORY

OR

/

MIXER

FIGURE E.

SR101 or SR109 channel input at-

SR110 to the remaining input. This set-up

FIGURE

INPUT TO

I

4ii~

SR101 or SR109 feeds the

SR110 feeds the

0 (off).

SRlO9s can provide a 16-

G.

The male ACCES-

MONITOR

OUT

F.

I

STAGE

SR110

TO STAGE

MONITOR

POWER

AMPLIFIER

ACCESSORY

INPUT

AND

OUTPUT

ACCESSORY

INPUT

AND

OUTPUT

FIGURE

16-CHANNEL MIXER CONNECTIONS

SORY INPUT AND OUTPUT Connector (8) of each
SR110 is connected to the female ACCESSORY OUT-

PUTIAUX

The SRllOs are connected through their MIX BUS

Connectors (10). With this set-up, all 16 channels are

available at each

trols
and varying one MASTER Control will not affect the
output of the other. Each SRllO output is fed to its
own power amplifier.

LEVEL Connectors of the SRlOls or SRlO9s.

(3)

of each SR110 are independent of each other,

SRl10. The MASTER Volume Con-

SPECIAL OPERATING INSTRUCTIONS

The following information is supplied to enable the

user to utilize the

in special or custom installations.

Multi-Track Recording Mixing

The SRllO may be used as a submaster or mixdown

panel for multi-track recording systems. The input to

SR110 can be a microphone preamplifier, record-

the

ing console channel output or tape recorder line out­put.

A single

Additional SRllOs may be added by interconnecting

the
(8,

9)

eight

Out

bused pairs.

Cable Extension

Should a longer cable length be required between
the SRllOs and their associated mixer, a length of
12-conductor, shielded cable and connectors may be
obtained from Shure Brothers
to 12m (40 ft) may be added between the SRllOs and
the console or mixer. Refer to the Circuit Diagram
(Figure M) for proper cable wiring.

Connecting a

An external VU meter may be connected to the
SR110 LlNE LEVEL output (6) with a series resistor

(see Figure H). Use a true VU meter (such as a

son 1349) and a resistor connected as shown. The

resistor should be a
ohm load, 0 VU is

SR110 is used for monophonic systems.

for a multi-track system. For example, for an

inlfour out system, use four SRllOs. For a 16

'ystem,

SRl10 Professional Monitor Mixer

VU

INPUT

use

Meter

+4

AND

OUTPUT Connectors

SR1lOs

M-watt carbon, 5%. With a 600-

dBm.

'Onnected

Inc. (see Parts List). Up

in

mix

Simp-

G.

I

TIP WlRE

3600

5%

I

TO LlNE LEVEL

OUTPUT PHONE JACK

I

O

RING WlRE
NOTE: NO CONNECTION TO SLEEVE REQUIRED.

FIGURE

H.

VU METER CONNECTION

0

I

i

I

SERVICE INSTRUCTIONS

Service

ponents of the highest quality, operating well within
their respective ratings to assure long life.

(See Guarantee)

SR110 Professional Monitor Mixer uses com-

The

WARNING

Voltages in this equipment are hazardous
to life. Refer servicing to qualified service
personnel.

I

Replacement Parts

Parts that are readily available through local elec­tronic parts distributors are not shown on the ac­companying Parts List. Their values are shown on the
Circuit Diagram (Figure M). Commercial parts not

readily available and unique parts
Parts List and may be ordered directly from the
tory.

The commercial alternates shown on the Parts List
are not necessarily equivalents, but are electrically and
mechanically similar, and may be used in the event
that direct factory replacements are not immediately
available. To maintain the highest possible perform­ance and reliability, Shure factory replacement parts
should be used. When ordering replacement parts,
specify the Shure Replacement Kit Number (RKC), de­scription, product model number and serial number.

Cover Removal

To service components inside the chassis, the pro­tective top cover must be removed. This is done by

removing eight screws from the top surface and lifting

the cover off.

are

shown

on

I

the

fac-

FIGURE

J.

SR110 TOP VIEW, COVER REMOVED

Fuse Replacement

The SRl10-2E (only) contains a 1/16A, Slo-Blo,
wired-in (pigtail) fuse which protects the power trans­former. Be sure to replace this fuse only with one of

identical value and size.

Printed Circuit Board Removal

The SR110 chassis contains a printed circuit board
assembly (see Figure

may be made accessible for servicing by disconnecting

K

and

leads
nuts securing individual channel Volume Controls
through R8 to the front panel. The board may be com-

pletely removed by unsoldering the 17 wires fastened
to the board.

dered board connections, make sure each wire is

identified for proper reconnection. This may be done

by affixing a piece of masking tape marked with the

connection or terminal letter to each wire.

Replace cover after servicing.

L,

IMPORTANT:

J).

The foil side of the board

and removing the eight knobs and

R1

When disconnecting sol-

CIRCUIT BOARD WIRE COLORS

I

Letter

NOTE:

6

Wire Color

A

B

C

D

E

F

G

H

Brown
White/Red
Orange
Yellow
Green
Blue
Purple

G

rav

Production variations may result in wire colors dif­fering from those in the

I

I

Letter I Wire Color

Orange (2)
Bare

Bare (Shield)

Red
Black
Red
Red
Blue

table.

Transistor and Diode Removal

All transistors and diodes used in the SRllO are

mechanically supported by their leads. When replacing

these devices, proper lead configurations must be fol-

lowed. Minimum soldering heat (preferably with a low­wattage soldering iron) should be used to avoid
damage to the device. Transistor lead codes are in­cluded in the Notes to Circuit Diagram (Figure

L).

Transistor and Diode Checking

Defective transistors and diodes may be located by
use of a standard ohmmeter such as a
Polarity of the ohmmeter must be verified before these

checks are made. Transistors and diodes must be

removed from the circuit before testing.

With a known diode orientation, measure the diode
resistance in the forward and reverse directions. The

lowest meter reading will establish the probe at the
cathode end (schematic symbol arrow points to cath-

ode) as the "minus" probe while the other probe will
be "plus." Some ohmmeters are not polarized in this
manner with relation to "volts plus probe" and "volts
minus probe." With the ohmmeter "plus" probe on the

a

anode end of
cathode end, the ohmmeter should read approximately
2000 ohms or less. With the meter probes reversed, a
reading of about 10,000 ohms or more should be ob-

tained. If either of these conditions is not met, the

diode should be replaced.

To check transistors, the ohmmeter should be set to
the 100- or 1,000-ohm scale. If all conditions in the
following table are met, the transistor may be

diode, and the "minus" probe on the

Simpson 260.

con-

sidered free of any major defect; if any of the following

conditions are not met, the transistor should be re-

placed. See Notes to Circuit Diagram (Figure L) for

transistor lead codes.

Ohmmeter Connections Ohmmeter Reading

NPN PNP

"Plus" Lead "Minus" Lead Transistor Transistor
Collector Emitter High High

Emitter Collector High High
Collector Base High Low

Emitter Base

Base Collector Low High
Base Emitter Low

*Not a significant measurement.

Service Illustrations

The pages that follow contain a Parts Location

Drawing for the printed circuit board (Figure

overall Circuit Diagram (Figure M). Foil circuit paths

*

Low

K)

and an

K.

are shown as shaded areas in Figure
Diagram shows all printed circuit board and
mounted electrical parts.

GUARANTEE

This Shure product is guaranteed in normal use to
be free from electrical and mechanical defects for a
period of one year from date of purchase. Please
retain proof of purchase date. This guarantee includes

all parts and labor. This guarantee is in lieu of
and all other guarantees or warranties, express or
implied, and there shall be no recovery for any con­sequential or incidental damages.

SHIPPING INSTRUCTIONS

Carefully repack the unit and return it prepaid to:

Shure Brothers Incorporated
Attention: Service Department
1501 West Shure Drive

Arlington Heights, Illinois 60004
If outside the United States, return the unit to your
dealer or Authorized Shure Service Center for repair.
The unit will be returned to you prepaid.

The Circuit

chassis-

ariy

REPLACEMENT PARTS LIST

Reference

Designation

*Parts listed as

Any orders received for piece parts where

Replacement

Kit No.*

RKC

Kits should be ordered by that kit number.

I

Qty.

RKC

(See

Part No.

Kit number is shown will be shipped in

Figures

Replacement Kit Consists Of:

K

and

Description

Printed Circuit Board Assembly
(with Potentiometers)

Capacitor, Electrolytic,

p,F, 25V

4
Capacitor, Electrolytic,

50

p,F, 35V

Capacitor, Electrolytic,

p,F, 35V

5
Capacitor, Electrolytic,

1

250 p,F, 40V
Capacitor, Electrolytic,

100 p,F, 25V

Capacitor, Electrolytic,

I

1000

,uF,

40V

Capacitor, Electrolytic,
250

p,F,

40V
Silicon Rectifier,
Diode, Silicon, Computer, 75V
Silicon Rectifier,
Fuse, Ac, Slo-Blo, Pigtail,

1116A (SRI 10-2E only)
Connector, Female,
Connector, Phono Jack,

Grounded Shell
Connector, Phone Jack,

3-Conductor, Open Circuit
Connector, Male, 3-pin Audio
Connector, Phone Jack,

3-Conductor, Two Circuits
Connector, Female,

Switched Ac (SR110 only)
Connector, 3-Pin AC (MAINS)

POWER
Ferrite Bead Ring

(SRllO-2E)

M)

50V, %A

IOOV, %A

RKC

1 l-pin

Non-

quantities.

Commercial

Alternate

None

Mallory

TNT405U050POA
Sprague TE1307;

CDE NLW 50-50
Sprague

CDE NLW 5-50
None

Sprague
Mallory MTA
100F35; CDE
NLW 100-25

None
None
Motorola 1

TI or GE IN4148

Motorola 1 N4002
Littelfuse 3.5.062

Amphenol 126-805
Switchcraft 351

Switchcraft 128
Switchcraft C3M

Switchcraft

None

None

Stackpole 57-0181

Ferronics 21 -031

TE1303;

TE1211;

N4001

1A

1128

J

;

7

REPLACEMENT PARTS LIST-(Continued)

Reference

Designation

MPI

M P2

M P3
M P4
M P5
PI

PLI
Q 1

Q2
Q3

Q4
Q5
R1 -R8

R36lS2

R36lS2

S1
S2
S3

TI

T2

T3
T3
W1

W1

-

*Parts

listed

Any

orders

Replacement

RKC9

RKCI

RKC65
RKC66

as

RKC

Kits

received

for

Kit No.*

-

-

-

-

-

-

-

2

-

-

-

-

-

-

-

-

-

-

-

-

-

-

should

piece parts

,

-

be

ordered by

where

Qty.

-

-

-

-

-

-

4

1

-

1

1

-

-

-

-

-

-

-

-

-

-

-

-

Replacement Kit Consists

Part No.

90F2085

90E2085

44C211

90AP2600
30F481
95A656

90E2600
86C349

86A336
86A348

86A334
86A335
46A053

46A054

46A073

55C112

B

-

55A116

51 B229
51 C228

51 A253
51 A259
95A632

90A1888

15A1202

that

kit

Kit

number.

number

is

shown

RKC

Of:

Description

Knob Assembly, Grey,
Individual Channel Volume

Knob Assembly, Black,
MASTER

Spring Shield
Connector Shell for
Screw, 4-40 x 7/16" (PI)

Connector, Male,
11-pin (less shell)

Lamp, Indicator, Neon

Transistor, Silicon, NPN
Transistor, Silicon, NPN

Transistor, Silicon, Low

Power, PNP
Transistor, Silicon, NPN
Transistor, Silicon, PNP

Potentiometer,

Volume

Potentiometer,

Volume/POWER OFF (SRI 10)

Potentiometer,

VolumeIPOWER OFF

(SRI 10-2E)
Switch, Slide, DPDT
Part of R36

Switch, Slide, DPDT, VOLTAGE

SELECTOR (SRI
Transformer, Output
Transformer, Headphones

Transformer, Power (SRI

Transformer, Power (SRI 10-2E)
Line Cord and 3-Conductor

Ac Plug Assembly (SRI

Line Cord and 3-Conductor Ac

Female Plug Assembly

(SRI 10-2E)

Cable, 12-Conductor
Shielded (specify length)

will

VolumeIPOWER OFF

50K, Channel

50K, MASTER

50k, MASTER

10-2E only)

be

shipped

in

RKC

PI

10)

10)

quantities.

Commercial

Alternate

None

None

None
Amphenol 126-946

-

Amphenol 126-804

Leecraft 36N1311

Motorola 2N5088;
TI 2N3711

TI TIS97

Motorola or Fairchild

2N5087
TI TIS92
TI TIS93

None

None

None

Switchcraft

46206LSR

-

None

None
None

None

None
Belden 17408

None

None

NOTES TO CIRCUIT DIAGRAM

General Transistor lead codes are shown in Figure L. Ac-

Shure part numbers are not shown in the Parts List
accompanying the Circuit Diagram (Figure M) if parts The following ground symbols denote:
are readily available through local electronics
suppliers. In these instances, the Circuit Diagram
shows only the reference designation and value of the
standard parts.

All capacitor values are shown in microfarads unless
otherwise designated. All non-electrolytic capacitors
are 100 working volts dc or more unless otherwise
specified. Electrolytic capacitors are shown in micro-

X

farads

All resistor values are shown in ohms (k=1000).
Resistors are %-watt, 10% tolerance unless otherwise
specified.

volts.

parts Chassis Ground

ceptable repla~etnent~ are shown in the Parts List.

/$7

Circuit

Printed Circuit Board Ground
Troubleshooting

the

source and power supply output (34V at pin
printed circuit board). If the output is distorted,
or not present, apply an input signal as described
under
that the input voltage to the board assembly is correct.
If an incorrect ac voltage is found on the board, per-

Ground

I-

-

6

A general troubleshooting process is as follows: If

SRI10 is completely "dead," check the ac power

M

of

low

Ac

Voltage Measurements

below, and determine

form Dc Voltage Measurements as described below to
isolate the problem area.

AC Voltage Measurements

The numbers within rectangular symbols
the Circuit Diagram denote the ac voltage at that point
under the following test conditions:

1. Voltage measured with respect to chassis unless
otherwise indicated.

2. Line voltage:
or 230V (SRl10-2E).

3. Test signal of 40 mV, 1000
pin 1-8 (for desired channel) and ground pin 11

of ACCESSORY INPUT AND OUTPUT connector

PI.

4. Measurements made with ac VTVM of 1 megohm

or greater input impedance.

5. Load across
J3-J5: 600 ohms total.

6. Ac voltage measurements may vary

values shown.

DC

Voltage Measurements

The numbers within elliptical symbols
Circuit Diagram denote the dc voltage at that point
under the following test conditions:

1. Voltage measured with respect to chassis unless
otherwise indicated.

2. Line voltage:
or 230V (SR110-2E).

120V, 50160

Hz

(SR110) or 115V

Hz

LINE LEVEL OUTPUTS Connectors

120V, 50160

Hz

(SR110) or 115V

u

applied across

*30% from

o

on

on the

3. No input signal applied.

4. Dc voltage measurements may vary
values shown.

5. Measurements made with VTVM of 11 megohms
or greater input impedance.

t20% from

Resistance Measurements

With the ac line cord disconnected from the ac
source and the POWER-OFF Switch in the OFF posi­tion, the following ohmmeter measurements may be

made:

1. Transformers may be checked for continuity of
each winding.

2. To test transistors and diodes, see Transistor and
Diode Checking.

C

NOTE: ALTHOUGH OUTLINES MAY VARY, LEADS ARE

ALWAYS FORMED AS SHOWN ABOVE.

C

FIGURE L.

TRANSISTOR LEAD CODES

ARCHITECTS' AND ENGINEERS' SPECIFICATIONS*

The Monitor Mixer shall be a rack-mounted, 120-volt,

50/60

Hz

line-operated all silicon transistor line level
mixer, designed for use with the Shure
Audio Console,
equipment which requires a stage monitor mixer sepa­rate from the program mixer. The Monitor Mixer can
also be used in multi-track recording applications as
a submaster mix panel or
nections between the Monitor Mixer and SR101 or
SR109 shall be made through a single multi-pin con­nector permanently fastened to the Monitor Mixer. A
parallel-wired female connector shall provide for inter­connection of additional Monitor Mixers.

The Monitor Mixer shall contain eight
ance,
circuitry, and one high-impedance, unbalanced, line
level input to its OUTPUT SELECTOR Switch for
monitoring program material. The Monitor Mixer out­puts shall consist of one three-pin male professional
audio connector and two standard
phone jacks. Each shall be a line level, 600-ohm, bal­anced output. The Monitor Mixer shall contain a MIX
BUS phono connector for interconnecting Monitor
Mixers.

unbalanced, line level inputs to its mixing

The Monitor Mixer output circuit balanced 600-ohm

All specifications apply to SRl10-2E except: operating voltage is 105-125
or 210-250 volts; non-switched ac receptacle is not provided.

SR109 Professional Mixer or similar

mixdown panel. Intercon-

SR101 Series 2

high-imped-

1/4

inch three-circuit

line shall have an output rated at +I2 dBm at less

than 1% distortion with a minimum clipping level of

19.2

dBm. The Monitor Mixer shall have a voltage gain

12 dB (program input) and a maximum input

of 40

21

sensitivity of

The input channel clipping level at 1

2.5V minimum and shall increase with channel settings
below 12.

The Monitor Mixer shall be enclosed in a metal,

rack-mounting enclosure housing with a scuff-resistant

vinyl-covered front panel. The dimensions shall be

44.5 mm in height, 483 mm in width, and 232 mm in
depth

(1% in. x 19 in. x 9% in.). The weight shall not

be more than 3.9 kg (8

The front panel shall contain eight rotary individual
channel Volume Controls, one rotary MASTER Volume
ControllPOWER-OFF Switch, a power-on indicator

lamp, an OUTPUT SELECTOR Switch, and a PHONES

Jack. A non-switched ac receptacle rated -for 500 watts

maximum load shall be provided on the rear panel.

Any Monitor Mixer not meeting all of the above
specifications shall be deemed unacceptable under
this specification. The Monitor Mixer shall be a Shure

Model

SR110.

mV for a

$4

dBm program output.

Ib, 8 02).

kHz

shall be