Shure uc2, uc58 User Manual

Shure Incorporated
222 Hartrey Avenue
Evanston IL 60202-3696 U.S.A.

UC UHF Wireless System

SERVICE MANUAL CHANGE NOTICE

UC2 UHF HAND-HELD TRANSMITTER

Changes or corrections have been made to this service manual. Update your service manual by replacing
the pages listed in the table below with the ones attached to this change notice.

CHANGES EFFECTIVE [DATE]

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your current manual

Revision 1 ALL Revision 2 ALL

Revision 2 pages:14,15,17,20,22,27,29 and 30 Revision3 pages:14,15,17,20,22,27,29 and 30

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attached to this notice

INSERT

SERVICE MANUAL REVISION HISTORY

Release Part Number Date Code

Original 25A1044 RI
Revision 1 25B1044 SB
Revision 2 25C1044 TB
Revision 3 25C1044 TK

E1999, Shure Incorporated

Printed in U.S.A.

UC2 Hand-Held UHF Transmitter

Characteristics

General

The Shure UC2 Hand-Held UHF Transmitter is a microprocessor­controlled microphone transmitter, operating in the 692 to 716 MHz and
774 to 862 MHz frequency range. The UC2 hand-held transmitter is
used in mid-level installed sound, rental, and concert sound applications.
Six frequency range variations are available.

Controls and Connectors

Service Manual

25C1044 (TK)

1

2

3

1. Mic Cartridge Grille (87 shown)

2. Battery Fuel Gauge LEDs

3. Power ON/OFF Switch

4. Audio Gain Control
Figure 1. UC2 Controls and Connectors

Service Note: Shure recommends that all service procedures be performed by a Factory­Authorized Service Center or that the product be returned directly to Shure Brothers Inc.

Licensing: Operation may require a user license. Frequency or power-output
modifications may violate this product’s approvals. Contact your country’s com­munications authorities.

48

5

7

6

5. 9 V Battery

6. Battery Cup

7. Group Selection Rotary Switch

8. Channel Selection Rotary Switch

1999, Shure Incorporated Printed in U.S.A.

25C1044 (TK)

Shure UC2 Hand-Held UHF Transmitter

Circuit Description

LIMITER

CONTROL INPUT

FROM
BATT.

CONTROL

MIC

ON / OFF

SWITCH

FET

BYPASS

PWR.
HOLD

CIRCUIT

AUDIO IN

+5V

REG.

UNREG. PWR.

PWR. OFF DETECT

SYNTH.

MB15A02

RF POWER

+5v

32.768 kHz

PLL CONTROL

4 MHz

LIMITER

CONTROL OUTPUT

TONE KEY

CIRCUIT

TONE CONTROL

BATTERY

MGMT.
& FUEL

GAUGE

MCU

MC68HC705

GROUP CHANNEL

RF MUTE RF MUTE

TONE KEY

CALL ID

4 MHz

EEPROM

(MEM)

Σ

AUDIO

OUT

Audio Section

FCC-Approved

VCO

Figure 2. UC2 Hand-Held Transmitter Circuit Block Diagram

Audio enters L200, an inductor used as an rf choke. The signal is
ac coupled through capacitor C200 into a user adjustable gain stage.
Resistors R202 and R203 set up a half-supply bias, and R204 sets the
input impedance for the stage.

The back-to-back diodes, D201, are used to keep the op-amp from
snapping to the rail and reverse phasing when the maximum input volt­age range is exceeded.

The 30 dB adjustable gain stage is built around U200A. The user
externally controls the gain of this stage. C206, C207, and C208 protect

Characteristics

2

25C1044 (TK)

Shure UC2 Hand-Held UHF Transmitter

the amplifier and bias circuits from rf interference. Due to its topology,
this stage is unique because it is non-inverting and allows for a gain less
than unity.

Audio then enters a buffer to the pre-emphasis network and the
compression stage. R213, R214, and C211 set up two corners for the
pre-emphasis network. The pre-emphasis boosts the high frequencies
before transmission.

This network feeds an NE575 compander, U202, that utilizes an
external amplifier, U201B. The compander performs a 2:1 logarithmic
compression of the audio signal. The pre-emphasis network also plays
a role in setting the hinge point (0 dB gain) of the compander.

From the compressor, the processed audio enters a low-pass filter,
U201D, and then a summing amplifier, U201C. The tone key (and for
J frequencies, the call ID signal) is added here to the processed audio
signal.

Transistors Q208 and Q209, with crystal Y200, form the tone key
oscillator circuit to provide a stable, continuous 32.768 kHz sine wave.
Transistor Q210 buffers the tone key signal before it is added to the
audio signal.

The tone key signal is used in the receiver to provide audio output
only when the tone key signal is present with the transmitted signal. If
the tone key or the transmitter is turned off, the receiver will be muted.

The tone key squelch eliminates receiver noise associated with
loss of a carrier. Q211 acts as a switch for toggling the tone key

UNMUTE

fed to a summing amplifier, U201C. R244, at the output of the summing
amplifier, helps prevent spurious oscillations from the op-amp. After
passing the ac coupling capacitor, C243, the signal is fed to the rf module
via the rf choke, L207.

D205; and various resistors. The meter works by comparing a divided
down version of the battery voltage (R250, R251) to two thresholds
(set by R252, R253, and R254), and lighting the appropriate LED.

(pcb), via switch S200. FET Q203 provides electrical reverse battery
protection by connecting the negative battery terminal to the pcb ground
only when the battery is connected with the correct polarity.

gives a clean, regulated 5 V supply to run the audio circuitry. The
regulator has appropriate bypass capacitors on its input and output.
Q201, Q202, Q212, Q213, and their respective resistors, provide
power management and timing.

; it is controlled via the microprocessor.

The tone key signal, along with the processed audio signal, is then

The battery meter circuit is comprised of U205; LEDs D203, D204,

A 9 Vdc battery provides power to the audio printed circuit board

The 9 Vdc then enters U203, a low dropout 5 V regulator, which

MUTE/

Circuit Description325C1044 (TK)

Shure UC2 Hand-Held UHF Transmitter

ETSI-Approved

This transmitter uses the same pcb as the domestic system, but it

requires a different topology and different parts.

A limiter is inserted between the pre-emphasis and the compressor

to limit the occupied bandwidth.

The buffer after the gain stage, U201A, is now an inverter with
pre-emphasis and 20 dB of attenuation. Previously bypassed, the
expander side of the NE575 (U202) is now activated and used as a
limiter. A sample of the audio is taken from the limiter output, U202,
pin 6, and sent to a control circuit that detects signals above a limiting
threshold. The comparator then sends a control signal to U202, pin 5,
which clamps the signal.

Rf Section

Processed audio enters R320, an internal potentiometer that is
adjusted for 45 kHz deviation (40 kHz for England), 100% modulation,
with a 6.8 dBu 1 kHz tone at the output of the compressor. For J fre­quencies, R320 is adjusted for 5 kHz deviation with 1 kHz tone injected
into the mic input, to give –23.47 dBu at U201, pin 7 (TPA4).

The audio is then fed to the tuning voltage pin of the voltage con­trolled oscillator (
locked-loop (
multiplier stages and results in a much higher degree of spectral purity.

The

VCO is shielded to prevent external rf fields from affecting its

operation. Regulated 5 Vdc power from the low drop-out regulator,
U311, is provided to ensure frequency stability with changes in battery
voltage.

The

VCO is capable of tuning from 782 to 806 MHz (FCC-approved),

with a 1 to 4 V tuning voltage range. At the output of the
signal splits into two paths. Frequency variations by country are given
in a table in the Service Procedures section.

The output of the
pin of the synthesizer, U304. The synthesizer’s internal circuitry divides
the rf signal down, as necessary. The synthesizer contains a quartz-con­trolled reference oscillator circuit operating from a 4.0 MHz crystal, Y302,
that is adjusted by trimmer C314.

The transmitter output frequency is user-selectable in groups of
compatible channels from 782 to 806 MHz for domestic groups. Fre­quency selection is made via microprocessor U303, which interfaces with
the user by means of the Group/Channel switches, S301 and S302.

The output of the synthesizer is a series of pulses integrated by a
passive loop filter (R316, C319, R317, C353, R318, C320) to produce a
control voltage signal. The control voltage signal is then connected to
the

VCO through buffer amplifier U306B, which is used to isolate the PLL

filter from the audio modulation signals.

VCO output is also coupled to the pre-driver and rf power

The
amplifier through a resistive network (R322, R324, R325) and a
coupling capacitor, C329.

VCO), which modulates the carrier directly. A phase

PLL) frequency-synthesized system eliminates the need for

VCO, the rf

VCO is coupled by C323 to the frequency control

Characteristics

4

25C1044 (TK)

Shure UC2 Hand-Held UHF Transmitter

The pre-driver stage, Q302, provides approximately 6 to 8 dB of
gain, which makes up for the pad. R326 and R327 provide base bias
for the transistor, while R328 sets its operating current.

L303 is an rf choke used to provide power to the stage, while L304,
C332, C333, C357, and C2 provide filtering/matching for the stage. The
collector of Q302 feeds into the power amplifier stage via coupling
capacitor C338 and a pi-matching network made up of C339, L305,
and C340.

The rf power amplifier, Q304, is a dual emitter
high-frequency low-noise device can provide +18 dBm out at its 1 dB
compression point. It is biased via base resistors R331 and R332. Its
operating current is controlled via emitter resistor R333.

L306 acts as a choke, and C349, C350, C355, and C356 provide a
good emitter bypass to ground. The amplifier output is matched to low­pass filter U1, via L307. The low-pass filter output couples to the printed
circuit board (pcb) via C347 and L308.

The transmitter can deliver +17 dBm (50 mW) maximum to the
antenna for domestic frequencies; JA and JB frequency transmitters can
deliver +10 dBm maximum to the antenna. During transmitter power-up
and frequency selection, the rf power is muted by bringing the gates of
Q303/Q305 low. This provides approximately 45 dB rf attenuation until
the

PLL has locked.

The transmitter rf is then unmuted by bringing the gates Q303/Q305
high. During transmitter power off conditions, voltage is first removed
from the
of the transmitter is not allowed to drift off frequency during power on/off
conditions.

VCO by bringing the base of Q301 high. Thus, the carrier signal

BJT. This high-gain,

Digital Section

Microcontroller Section

Memory Section

The digital section contains several circuitry blocks.

The microcontroller section consists of the U303 microcontroller.
The rotary switches indicate the UHF frequency group and channel. A

4.000 MHz oscillator provides the operating frequency to the microcon­troller. The oscillator circuit includes C300, C301, and Y301. U5, R306,
and C305 form the reset circuit. U5 is the reset IC that resets the U303
microcontroller if the 5 Vdc normal operating voltage falls below 4.3 Vdc.
C302 and C303 form the power supply bypass filter circuit.

The memory section consists of U302, a non-volatile, Electrically
Erasable/Programmable Read Only Memory (

EEPROM) that stores the

Circuit Description525C1044 (TK)

Shure UC2 Hand-Held UHF Transmitter

mapping of the compatible groups and channels. The microcontroller
serially communicates with this part via data and clock lines to read the
frequency corresponding to the Group and Channel position.

The ability to write to the memory occurs during factory programming

only. During normal usage, this memory is used as a look-up table only.

R335 and R305 resistors allow the clock and data lines to be driven
independently of the microcontroller port pin states during in-circuit pro­gramming of the

EEPROM.

Battery Management Section

The U303 microcontroller provides low battery shutdown. The shut­down threshold is 1.88 Vdc ± 10%. A voltage lower than the shutdown
threshold on U303, pin 17, shuts down the transmitter. Resistors R308
and R309 divide down the battery voltage for U303; a battery voltage
less than 5.65 Vdc must shut down the transmitter.

This auto shutdown disables the audio tone key mix, mutes the rf
output, and powers down the rf output amplifier section. The current
draw from a 9 Vdc battery in this state is 14 ± 2.0 mA, and the battery
fuel gauge is not functional. Turning off the power switch completely
shuts off the transmitter.

The audio circuit description section provides information for the
battery fuel gauge circuit description.

Rotary Switches for Frequency Selection

A 10-position Group switch (S302) and a 16-position Channel switch
(S301) select the transmitter frequency. Both rotary switches share the
same U303 microcontroller port pins (3 through 6) for a multiplexed
switch read operation. The individual switches are selected by U303,
pins 7 and 8. Resistors R4, R300, R302, and R303 are the pull-ups for
the switch position read. Diode packs D301 through D304 isolate the
switches during the multiplexed read operation.

The multiplexed scheme to read switches does not allow incorporat­ing switch change detection based on interrupts. Also, the switches can­not be constantly scanned to determine changes because the scanning
frequency being in audio range is difficult to filter out.

In a steady state, the switch selector common pins are inputs to the
U303, pins 7 and 8, while U303, pins 3 through 6, are outputs. In this
state, pins 4, 5, and 6 are held low while pin 3 is held high. This forces
logic high level on switch selector pins if the switches are set on odd
positions. For even position settings, the contact on pin 1 is open from
the switch common pin and the internal pull-down resistors force logic
low to U303, pins 7 and 8.

Any switch change is comprised of state toggle from odd to even,
and vice versa. Only this change is detected, and it is followed by a
multiplexed switch read, in which U303, pins 7 and 8, become selectively
grounded outputs to read the selected switch’s state on pins 3 through 6.

A multiplexed switch read is preceded by tone key and rf mutes.
This mutes the audio in the receiver to allow a quiet change to another
frequency.

Characteristics

6

25C1044 (TK)

For JA frequencies, the Group switch has 16 positions, and the

Channel switch has 10 positions.

Power Switch and Mute Interface

When a transmitter is turned off, the PWRDN signal goes to logic low
on U303, pin 19. This immediately disables the tone key, and the power
hold circuit automatically kicks in to bypass the power switch. This is
followed by 500 mS of delay, and then the rf is muted and turned off.
The power hold circuit is also disabled at this point, and the transmitter
shuts off.

Shure UC2 Hand-Held UHF Transmitter

Circuit Description725C1044 (TK)

Shure UC2 Hand-Held UHF Transmitter

Notes

Notes

This page intentionally left blank.

8

25C1044 (TK)

Shure UC2 Hand-Held UHF Transmitter

Functional Test

Verify operation and reported malfunction, referring to the product
User’s Guide for a description of the unit as well as information on its
operation, troubleshooting, and technical data.

Disassembly and Assembly

! CAUTION !

Observe precautions when handling this static-sensitive device.

Disassembly

Handle

1. Remove the microphone cartridge from the UC2.

2. Use a pair of needlenosed pliers to remove the circuit board
retaining ring from inside the handle.

3. Push the bezel tab-snap in the handle behind the contact pcb to
remove the bezel and switch actuator.

4. Slide the circuit board out by pushing on the battery connectors.

Bezel

Switch actuator

Tab

Tab

Right side view of microphone

Contact pcb

Circuit board subassembly

Figure 3. Bezel Removal

Disassembly925C1044 (TK)

Shure UC2 Hand-Held UHF Transmitter

ÁÁÁ

Ball screen

Retaining

ring

Rf circuit

board

Microphone

cartridge

Contact

board

(SM58 shown)

Audio circuit

board

Gain control

Handle

Gain control

access

Bezel

Switch

actuator

9 Vdc alkaline

battery

Battery cup

Figure 4. UC2 Hand-Held Transmitter, exploded view.

Reassembly

Disassembly and Assembly

To reassemble the unit, reverse the disassembly steps given above:

1. Slide the circuit board back into the handle.

2. Reinstall the retaining ring, switch actuator, bezel, and the
microphone cartridge.

10

25C1044 (TK)

Service Procedures

Measurement Reference

dBu is a measure of voltage, and dBm is a measure of power.

For example, the HP8903 should be labeled dBu instead of dBm
because it is a voltage measurement. These two terms are often used
interchangeably even though they have different meanings.

Audio levels in dBu are marked as dBm on the HP8903.

0 dBV = 2.2 dBu

0 dBu = 0 dBm, assuming the load = 600 Ω

Test Equipment

Most test equipment needed is described in the Shure Wireless
Service Equipment Manual. The following test equipment (or approved

equivalent) is also needed.

Shure UC2 Hand-Held UHF Transmitter

dB Conversion Chart

Table 1

Test Equipment

Equipment Type Model

Digital multimeter Fluke 87
Rf signal generator Hewlett-Packard 8656B
Frequency counter Hewlett-Packard 53181A

Spectrum analyzer (domestic) Hewlett-Packard 8590L

Spectrum analyzer (JA, JB) Hewlett-Packard 8591E

Shure UC4 receiver Shure UC4

Brass ring for use with test head PT1838–Y

BNC to “rocket launch” cable. For use on

Japan PCB versions “N” and earlier

BNC(male) to unterminated 50W test cable

*Audio levels in dBu are marked as dBm on the HP8903B.

Test Equipment Set-Up

The alignment procedure is sequential and does not change,

unless specified.

1. Use the following test cables for all RF test points: Use PT1824
cable for European and USA models. For the Japan models use
the 95C8418 test cable for PCB versions “N” and earlier.

2. Keep the test cables as short as possible (less than 12 inches).

3. Include the insertion loss of the cables and connectors for all rf
measurements.

4. Dc voltages may be present at rf test points. As a precaution,
use dc blocks to protect the test equipment.

Audio analyzer *Hewlett-Packard 8903B

Test head PT1840

95C8418

PT–1824

Test Equipment Set-Up1125C1044 (TK)

Shure UC2 Hand-Held UHF Transmitter

Test Set-Up

1. Desolder the printed circuit boards (pcbs) and pull them apart.
When the pcbs are desoldered, leave the battery contacts
soldered to the audio board for powering up the unit.

2. Remove C347 and connect the respective RF test cable between
TPRF1 / RF GND and a frequency counter.For Japan models
with PCB version “N” and earlier, do not remove C347. Connect
a 95C8418 cable between J2 and the frequency counter.

3. Use the PT1843 cable to connect the audio board to the rf board
through the 11-pin board interconnects (J200, J300, side 2).

4. Set the audio GAIN potentiometer (R207, side 1) to minimum,
full counter-clockwise (CCW).

5. Apply + 9 Vdc across the battery terminals (J201, J202, side 2).

6. Toggle the power switch, S200, to turn on the UC2 transmitter.

7. Set the UC2 Group and Channel switches, S301 and S302,
according to the group designators on the board and the
settings given in Table 2.

Table 2

Group Carrier Frequencies and Tuning Voltages

(in order by carrier frequency)

Group

Group

Group

Code

Switch

(S101)

UA A 4 0 805.500 3.7 45
UB F 1 A 703.750 2.6 45
MB B 1 3 805.500 2.2 15

JA C 0 2 805.500 3.7 5
JB D 4 2 807.500 3.8 5

KK E 5 5 851.125 2.9 15
MC B 1 1 774.125 1.3 ±0.25 15
MD B 3 7 805.500 2.2 15

Table 2 lists the group carrier frequencies, switch settings,

and tuning voltages for all the alignment tests that follow.

Channel

Switch

(S102)

Carrier

Frequency

(MHz)

VCO Tuning

Voltage

(TP30)

Deviation

(kHz)

Service Procedures

12

25C1044 (TK)

Shure UC2 Hand-Held UHF Transmitter

1

1

U203

VCO

U501

AUDIO SIDE 1

+5V

Q212

Q201

Y200

Adj

C510

Q213

C216

1

TP30

P201

P200

D201
C200

J205

RED

S302

TPRF1

GREEN

U200

Q220

RF GND*

J2*

TP18

Q304

R40*

U205

Q202

Q203

Q204

GND

+9V

S200

Q209

TP10

RF SIDE 1

S301

Y302

*J2 and R40 are placed for JA, JB frequencies only. RF GND is accessed thru a hole in the pcb.

C251

C210

Q211

C223

TP4

C221

C213

TP10

Q210

J202

TP2

J201

TP16

C314

Q208

C227

L302

Q301

AUDIO SIDE 2

+9V

TP6

RF SIDE 2

U304

Q303

C315

D302

D301

U5

D304

D303

J300

TP+9

TP30

C303

C324

U306

C353

R320

+5V

C27

U302

C308

C336

C222

C291

Q3

J200

U311

C243

Q305

TP4

TP6

C309

TP+9

TP18

L207

TPRF1

L300

Q2

U201U202

C214

U1U1

U303

Y301

R25

Q1

1

C347

R39

L308

R7

L2

PAD

P204

P203

L1

U2

J301

J302

Figure 5. UC2 Major Test Component Locations

Test Set-Up1325C1044 (TK)

Shure UC2 Hand-Held UHF Transmitter

Alignment

Frequency

Use this service procedure to correctly align the transmitter’s
operating (output) frequency. C510 tunes the voltage-controlled
oscillator (VCO) to the operating frequency selected, with a 1 – 4 Vdc
tuning range.

C314 adjusts the reference oscillator on the synthesizer, U304.

RF GND: FEED THRU

HOLE ON PCB

FREQUENCY COUNTER

CH 2

CH 1

AUDIO ANALYZER

RF

GND

S302

RED

S301

GREEN

*R40 and J2 are placed for JA, JB frequencies only.

J2*

R40*

TPRF1

C510

U501

C314

TP30

UC2 Transmitter Frequency Counter

Audio Analyzer

Power: ON (+9 Vdc) Operating freq: See Table 2 Connect + : TP30

Operating freq: See Table 2 Connect CH 2: TPRF1 and GND Connect – : RF GND

Channel switch: See Table 2 Measurement: DC level

Group switch: See Table 2 For Japan models with PCB versions:

“N” and earlier connect to J2

(pcb rf side 1)

Figure 6. UC2 Frequency Test Set-Up

1. Put a dc voltmeter across TP30 (tuning voltage line) and

RF GND.

2. Adjust the

VCO trimmer, C510, until the voltmeter reading

matches the appropriate entry in Table 2, ± 0.125 Vdc.

3. Adjust the variable capacitor, C314, until the frequency counter
measurement matches the appropriate frequency in Table 2,
± 1 kHz.

4. Leave the test cable connected to the rf output.

5. The dc voltmeter can be removed from TP30.

Service Procedures

14

25C1044 (TK)

Power Output Measurement

The output power measurement ensures that the output signal is
strong enough for sufficient range when the system is in use. The output
power measurement also verifies that the output power is not above the
specified maximum level, to ensure compliance with regulatory agencies
standards.

SPECTRUM ANALYZER

Shure UC2 Hand-Held UHF Transmitter

RF GND: FEED THRU

HOLE IN PCB

RF

GND

S302

RED

S301

GREEN

J2*

R40*

TPRF1

C510

U501

TP30

C314

*R40 and J2 are placed for JA, JB frequencies only.

UC2 Transmitter Spectrum Analyzer

Power: ON Frequency: See Table 2

Operating freq: See Table 2 Span: 200 MHz

Group switch: See Table 2 Reference voltage: 20 dBm

Channel switch: See Table 2 Peak search: ON

Signal track: ON

Marker: ON

Figure 7. UC2 Power Output Measurement Test Set-Up

1. Remove the BNC cable end from the frequency counter and
connect it to the 50 Ω input of the spectrum analyzer.. Use the
equipment settings shown in Figure 8.

2. Measure the output power. The output power should be:

UA, UB, MB, MC, MD

16 + 1 / – 2 dBm

frequencies:

KK frequencies: 14 + 1 / – 2 dBm

For J frequencies, with C347 in place,

adjust R40 to obtain 8.8 ± 0.5 dBm.

3. Turn the UC2 power OFF.

4. Disconnect only the BNC end of the RF test cable from the
spectrum analyzer.

Alignment1525C1044 (TK)

Shure UC2 Hand-Held UHF Transmitter

Deviation

Deviation must be set to make sure the companding systems be­tween the transmitter and receiver correctly track each other. The level
coming out of the transmitter’s audio compressor must match the level
going into the receiver’s audio expander. A fixed gain structure does not
ensure an exact match, primarily because of variations in voltage­controlled oscillators (VCOs).

Option 1 – Using a UC4 or U4S Receiver

This test requires a UC4 or a U4S receiver and is designed to tune
the transmitter regardless of the accuracy of the receiver’s tuning. It is,
however, recommended that a properly-tuned receiver be used to per­form the transmitter deviation adjustment.

Reference Voltage

1. Connect the rf signal generator to one of the receiver’s
antenna ports.

2. Turn the UC4 or U4S receiver ON.

3. Set the receiver frequency to match the transmitter frequency.

4. Set the rf signal generator frequency to match the transmitter
frequency.

5. Modulate the generator frequency with 1 kHz audio at a
–60 dBm output level. See Table 2 for deviation.

6. Set the tone key switch (S501 for the UC4, S201 for the U4S)
to the OFF position.

7. Connect the ac voltmeter to the unbalanced output of the
receiver.

8. Read the ac voltage.

Record this voltage. This is the deviation reference voltage.

9. Turn off RF output.

UC4 RECEIVER (BACK)

SQUELCH

UC4 RECEIVER (FRONT)

AB

AUDIO ANALYZER

RF SIGNAL GENERATOR

UC4 Receiver Audio Analyzer Rf Signal Generator

Output: Unbalanced Measurement: AC level INT: FM

Gain: Maximum Filters: INT: 1 kHz

Squelch: Mid Low-Pass (30 kHz): ON Output amplitude: –60 dBm

Tone Key (S501): OFF High-Pass (400 Hz): ON Frequency: See Table 2

Group switch: See Table 2 Deviation: See Table 2

Channel switch:

See Table 2

DC BLOCK

NOTE: DC VOLTAGES ARE PRESENT
AT MOST RF TEST POINTS. USE A
DC BLOCK ON THE RF SIGNAL
GENERATOR TO PROTECT
TEST EQUIPMENT.

Figure 8. Deviation Reference Voltage Test Set-Up,
Using a UC4 or U4S Receiver

Service Procedures

16

25C1044 (TK)

S501

(TONE KEY SWITCH)

TK ON TK OFF

Adjustment Voltage

1. Remove the RF test cable from TPRF1 and GND, and replace
C347. For Japan models PCB version “N” and earlier remove
cable from J2.

2. Reassemble the printed circuit boards. Use a PT1840 test head
and brass ring (PT1838-Y) to connect the audio analyzer to the
UC2 audio input (J205). Turn ON the Low-Pass (30 kHz) and
High-Pass (400 Hz) filters on the audio analyzer.

For bench testing, the audio analyzer can be directly connected
to the contact board gold contacts with clip leads.

3. Disconnect the rf signal generator from the UC4 receiver and
return the UC4 tone key switch to the ON position.

4. Adjust the audio analyzer output level (typically = –2.2 dBu) to
measure the following at TPA4 (U201, pin 7) :

Shure UC2 Hand-Held UHF Transmitter

See Figure 10 for equipment set-up and equipment settings
for the rest of this test.

S501

(TONE KEY SWITCH)

UA, UB MB, MC,

–6.8 dBu ± 0.2 dB

(354 mV ± 1 mV)

AUDIO ANALYZER

MD

– 16.3

dBu

(118 mV ±

1 mV)

JA JB KK

–26.5dBu
(36.7mV

1 mV)

– 23.47

±

(52 mV ± 1

dBu

mV)

(133 mV ± 1 mV)

AUDIO
SIDE 1

– 15.3 dBu

TPA4 –

U201,

pin 7

UC4 Receiver UC2 Transmitter Audio Analyzer

Output: Unbalanced Power: + 9 Vdc Measurement: AC level

Gain: Maximum Gain: Minimum Frequency Output: 1 kHz

Squelch: Mid Group switch: See Table 2 Filters:

Alignment1725C1044 (TK)

Shure UC2 Hand-Held UHF Transmitter

Tone Key (S501): ON Channel switch: See Table 2 Low-Pass (30 kHz): ON

High-Pass (400 Hz): ON

Figure 9. Deviation Adjustment Voltage Test Set-Up,
Using a UC4 or U4S Receiver

5. Connect the unbalanced output of the UC4 to the input of the
audio analyzer (ac voltmeter).

6. Take a radiative measurement by holding the battery of the UC2
next to the receiver’s antenna.

7. Turn the transmitter ON and adjust R320 until the ac voltmeter
on the receiver reads the same as the deviation reference
voltage, measured above, ± 0.1 dB; or ± 0.2 dB for JA, JB
frequencies.

AUDIO ANALYZER

S501

(TONE KEY SWITCH)

VCO

RF
SIDE 1

UC4 Receiver UC2 Transmitter Audio Analyzer

Output: Unbalanced Power: + 9 Vdc Measurement: AC level

Gain: Maximum Gain: Minimum Frequency Output: 1 kHz

Squelch: Mid Group switch: See Table 2 Filters:

Tone key (S501): ON Channel switch: See Table 2 Low-Pass (30 kHz): ON

High-Pass (400 Hz): ON

Figure 10. Deviation Reference Voltage Test Set-Up,
Using a UC4 or U4S Receiver

R320

Service Procedures

18

25C1044 (TK)

Shure UC2 Hand-Held UHF Transmitter

Option 2 – Using a Modified SC4 IF Receiver

Deviation tests can also be performed using a modified SC4 IF
receiver. For instructions on modifying an SC4 receiver, consult the
Shure Service Equipment manual.

Reference Voltage

1. See Figure 12 for equipment test set-up and equipment settings.

2. Connect the rf signal generator output to the input port (L) of a
Zad-1 mixer

3. Connect the output port I (intermediate frequency) of the Zad–1
mixer to antenna input B of the SC4 IF receiver.

4. Turn the SC4 IF receiver ON and set the tone key switch on the
front panel of the SC4 IF receiver to OFF.

5. Connect the audio voltmeter to the receiver’s unbalanced output.

6. Measure the output voltage.

Record this voltage. This is the deviation reference voltage.

Use the same Zad-1 mixer connections for the next adjustment test.

ZAD–1 MIXER

R

NOTE: DC VOLTAGES ARE
PRESENT AT MOST RF TEST
POINTS. USE A DC BLOCK
ON THE RF SIGNAL GENERATOR
TO PROTECT TEST EQUIPMENT.

I

L

DC BLOCK

RF SIGNAL GENERATOR

ANTENNA INPUT B

SC4 IF Receiver Audio Analyzer Rf Signal Generator

Output: Unbalanced Measurement: AC level INT: FM

Gain: Maximum Filters: INT: 1 kHz

Squelch: Mid Low-Pass (30 kHz): ON Output amplitude: + 7 dBm

Tone Key switch: OFF High-Pass (400 Hz): ON Frequency: 10.7 MHz

Operating freq: See Table 2 Deviation: See Table 2

MODIFIED SC4 IF RECEIVER

TONE KEY SWITCH: OFF

AUDIO ANALYZER

AUDIO OUT

Figure 11. Deviation Reference Voltage Test Set-Up,
Using a Modified SC4 IF Receiver

Alignment1925C1044 (TK)

Shure UC2 Hand-Held UHF Transmitter

Adjustment Voltage

1. Disconnect the rf signal generator from the SC4 IF receiver.

2. Set the SC4 tone key switch on the SC4 front panel to ON.

3. Connect the audio analyzer output to the MIC input of the
transmitter, using the test head or clip leads to the gold spring
contacts.

4. Turn the UC2 power back ON.

5. Adjust the audio analyzer output level (typically = –2.2 dBu) to
measure the following at TPA4 (U201, pin 7) :

UA, UB MB, MC, MD JA, JB KK

–6.8 dBu ± 0.2 dB

(354 mV ± 1 mV)

See Figure 14 for equipment set-up and equipment settings
for the rest of this test.

– 16.3 dBu

(118 mV ± 1 mV)

– 23.47 dBu

(52 mV ± 1 mV)

– 15.3 dBu

(133 mV ± 1 mV)

AUDIO
SIDE 1

TPA4

(U201, PIN 7)

AUDIO ANALYZER

TEST HEAD

UC2 Transmitter Audio Analyzer

Power: +9 Vdc Measurement: AC level

Gain: Minimum Frequency Output: 1 kHz

Group switch: See Table 2 Filters:

Channel switch: See Table 2 Low-Pass (30 kHz): ON

High-Pass (400 Hz): ON

Service Procedures

Figure 12. Deviation Adjustment Voltage Test Set-Up,
Using a Modified SC4 IF Receiver

20

25C1044 (TK)

Shure UC2 Hand-Held UHF Transmitter

6. Connect the UC2 rf output test cable BNC end to the input port
(R) of the Zad-1 mixer.

7. Connect the rf signal generator, and set the frequency to the
operating frequency (from Table 2) minus 10.7 MHz.

8. Turn ON the UC2 and adjust R320 until the audio voltmeter
connected to the unbalanced output of the UC4 reads the same
as the deviation reference voltage, measured above, ± 0.1 dB,
or ± 0.2 dB for JA, JB frequencies..

TRANSMITTER

AUDIO

IN

ANTENNA

OUTPUT

NOTE: DC VOLTAGES ARE
PRESENT AT MOST RF TEST
POINTS. USE A DC BLOCK
ON THE RF SIGNAL GENERATOR
TO PROTECT TEST EQUIPMENT.

ZAD–1 MIXER

R

I

L

DC BLOCK

RF SIGNAL GENERATOR

ANTENNA INPUT B

MODIFIED SC4 IF RECEIVER

AUDIO OUT

TONE KEY SWITCH: ON

AUDIO ANALYZER

SC4 IF Receiver UC2 Transmitter Audio Analyzer Rf Signal Generator

Output: Unbalanced Power: + 9 Vdc Measurement: AC level INT: FM

Gain: Maximum Gain: Minimum Output: 1 kHz INT: 1 kHz

Squelch: Mid Filters: Output amplitude: + 7 dBm

Tone Key switch: ON Low-Pass (30 kHz): ON Deviation: See Table 2

High-Pass (400 Hz): ON Frequency: Oper. Freq.

minus 10.7
MHz

Figure 13. Deviation Adjustment Voltage Test Set-Up,
Using a Modified SC4 IF Receiver

Alignment2125C1044 (TK)

Shure UC2 Hand-Held UHF Transmitter

Product Specifications

After tuning, the unit should meet the following specifications.

Specification Minimum Typical Maximum

Current drain 50 mA 60 mA 70 mA

Frequency –1.0 kHz See Table 2 +1.0 kHz
Audio freq response @ 100 Hz wrt 1 k –5.0 dB –4.0 dB –3.0 dB
Audio freq response @ 10 KHz wrt 1 k +8.0 dB +9.0 dB +10.0 dB

UA, UB:

System S/N @ 45 kHz, A weighted 95.0 dB 100.0 dB –
Output power, UA, without C347 14.0 dBm 16.0 dBm 17.0 dBm

MB, MC,MD

System S/N @ 1% THD, A weighted 80.0 dB 85.0 dB –
Output power, without C347 14.0 dBm 16.0 dBm 17.0 dBm

KK:

System S/N @ 1% THD, A weighted 80.0 dB 85.0 dB –
Output power, without C347 12.0 dBm 14.0 dBm 15.0 dBm

JA, JB:

System S/N @ 1% THD, A weighted 85.0 dB 90.0 dB –
Output power, at J2, with C347 in place 8.3 dBm 8.8 dBm 9.3 dBm

Service Procedures

22

25C1044 (TK)

Bench Checks

Dc Problems

Make all dc measurements with respect to the rf ground unless
otherwise specified. Connect the rf and audio printed circuit boards
together via the 11 pin connector, the battery contacts, and the “D” board.

n Make sure the battery voltage is between 6 and 9 Vdc. Make

If incorrect voltage is present:

n Trace the dc back to the voltage regulator.

n Check the biasing resistor values around Q301.

n Check the power switch.

n Look for open coils, cracked parts, reversed polarity capacitors,

Make sure that:

Shure UC2 Hand-Held UHF Transmitter

sure TP+9 has this voltage. Check for the correct Vcc and +5 V
rf at Q301.

or solder shorts. If there is a short to ground from 5 V, try to
isolate different parts of the circuit.

Rf Problems

n The rf OFF signal changes from +5 Vdc at power up and power

down to 0 Vdc during normal operation. Trace the signal to the
microprocessor. Q301 should be saturated during normal
operation.

n Battery voltage appears at TP+9, U311, pin 6. Check for

reversed polarity capacitors, C308 and C309. Check for open
coil, L300.

n If the carrier is out of specification by less than 40 kHz and can-

not be corrected by adjusting C314, put the transmitter on the
operating frequency (see Table 2). Measure and adjust the dc
voltage at TP30. (See Table 2 for frequency variations.) If the
carrier still cannot be trimmed properly, then check C314, C313,
and Y302. If they are correct, replace the synthesizer.

If the carrier frequency is not in the correct frequency range shown in
Table 2, or is unstable, the loop is unlocked.

n Check dc voltage at TP30. If it is 0 V or +5 V, look for a short.

n Check the solder connections at the contact board, VCO, micro

processor (traces LE, D, and CK), and synthesizer U304. If the
connections are good and there is no 4.0 MHz oscillation at
U304, pins 1 and 2, replace the crystal, Y302.

n Check the values and polarity of the loop filter: R316, C319,

R317, C353, R318, C320, C354, U306B, R319, R320, and
R321. Check the bias voltage of U304, pins 3 and 4, and
U306B, pin 8. As a last resort, replace the synthesizer, U304.

Product Specifications2325C1044 (TK)

Shure UC2 Hand-Held UHF Transmitter

Low Rf Output Power

n Check the polarity/soldering of the output low-pass filter, U1.

(Rf IN is marked with a dot.)

n Check for opens or shorts on output coil L308.
n Check the polarity of Q304.
n Verify the dc bias of Q302 and Q304. Check L303, L304, and

L306, if no bias. Verify that the rf MUTE signal changes from
0 Vdc at power up and power down to +5 Vdc during normal
operation. If Q303 and Q305 are not in a low impedance state
during normal operation, the rf power at the antenna port will be
attenuated by about 45 dB.

n Check for missing ground connections.
n Check the dc level at the VCO Vcc pin. If no dc power,

check L302.

n Verify the VCO output power.
n Partially isolate the VCO from the rest of the circuit by removing

C323. The carrier frequency will no longer be locked, but the
output power from the VCO should be around –1 ± 2 dBm into a
50 Ω load.

n If the power out of the VCO is still low, the problem is in the VCO.
n Check the values of R322, R323, R324, R325, and C329.
n Isolate components starting from the antenna and working back

to the rf power amp.

n Check the values/continuity of the input and output matching net-

works for Q302, Q304 (C329, C338, L305, C339, C340, L307).

n Check the values of the bypass capacitors C357, C2, C332,

C333, C334, C335, C360, C341, C342, C349, C350, C355,
C356.

n As a last resort, replace Q302 or Q304.

Excessive Current Drain

n Try isolating different sections of the circuit: rf, audio, digital.

Look for reversed polarity capacitors or wrong resistor values.
Check the voltage regulators.

Deviation Problems

n If R320 cannot be adjusted to obtain the deviation reference

voltage (see the Service Procedures section), try to isolate the
problem to the audio or rf section. Check the value of R320. To
check the rf section, set the transmitter frequency (see Table 2),
and verify the tuning voltage of the VCO.

n Check the audio section by applying audio to the mic input. With

an oscilloscope, make sure audio is present at TPA7. If not,
work backwards towards the input.

Bench Checks

24

25C1044 (TK)

Audio Problems

No Tone Key

Shure UC2 Hand-Held UHF Transmitter

No tone key means that the 32.768 kHz tone key sidebands are not
visible when the carrier is viewed on a spectrum analyzer. If tone key
levels are there but are too low, the deviation is off and needs to be
recalibrated. They should be, roughly, –23 dBc ± 3 dB.

n Apply a 1 kHz tone at a level of 0 dBu to the audio input with the

audio gain pot at minimum.

n If the carrier on the spectrum analyzer does not show any devi-

ation, check part integrity and audio path continuity between
U201, pin 14, and the VCO.

n If the spectrum analyzer shows a deviated carrier, probe for a

32 kHz signal at TPA6 and I209 and continue to the next step.

n If there is a signal at I209 but not at TPA6, then the mute circuit

through Q211 is being activated. Verify that the logic signal at
Q211, pin 1, is logic low. If it is low, replace Q211. If it is not low,
check the line for a short to +5 V. If there is no short, the micro­processor is defective and must be replaced.

n If there is a 32 kHz signal at both I209 and TPA6, replace R236.

n If there is not a 32 kHz signal at either I209 or TPA6, there is

something wrong with the tone key circuit or the tone key supply
voltage. If the tone key supply voltage (U200, pin 8) is less than
2 V, there is a problem with one or more of the following com­ponents: R261, R264, R265, R266, C238, Q220, C237, R232,
or R260.

n If the voltage at U200, pin 8, is greater than 2 V, the problem is in

the tone key circuit itself. Check for shorts and opens. Replace
parts in this circuit beginning with the crystal until the 32 kHz
oscillation returns.

No Audio

n View the carrier on the spectrum analyzer. If there are not

32 kHz tone key sidebands around the carrier, follow the steps
above for “No Tone Key.”

n Verify +9 V, half-supply bias, and ground connections to U200.

n Verify +9 V, half-supply bias, and ground connections to U201.

n Follow the audio path from where audio is applied until the point

of discontinuity is reached and replace the appropriate part.

Product Specifications2525C1044 (TK)

Shure UC2 Hand-Held UHF Transmitter

Notes

Notes

This page intentionally left blank.

26

25C1044 (TK)

Shure UC2 Hand-Held UHF Transmitter

Replacement Parts and Drawings

Parts Designations

The following comments apply to the parts list and the schematic:

Resistors: Unless otherwise noted, all resistors are surface-mount

1

0603 size, with

/10 W rating and 1% tolerance.

Capacitors: Unless otherwise noted, non-polarized capacitors are
surface-mount

NPO dielectric types with a 100 V capacity and a 5%

tolerance, and polarized capacitors are tantalum types.

Table 3

UC2 Model Frequency Variations

Printed Circuit Boards

(in order by frequency)

Country

Code

UA U.S.A. and Canada 782 – 806 MHz 90UA8792

UB U.S.A. 692 – 716 MHz 90UB8792
MB Europe 800 – 830 MHz 90MB8792
MC Netherlands 774 – 782 MHz 90MC8792
MD Scandanavia 800 –820 MHz 90MD8792

JA Japan 797 – 806 MHz 90JA8792
JB Japan 806 – 810 MHz 90JB8792

KK United Kingdom 838 – 862 MHz 90KK8792

Country

Designation

Frequency

Range

UC2 Printed

Circuit Board #

Table 4

Replacement Parts

Reference

Designation

MP1 (1)Actuator/(3)Gold mic contact/(1)Retaining ring RPW624
MP2 Battery snap (positive) 56A317
MP3 Battery snap (negative) 56A318
MP4 Bezel 65A8299
MP5 Compression disc (in battery cup) 38A180
MP7 Battery Cup 65A8300A
MP8 Handle 65A8301A
MP9 3–pin gold interconnect header for headboard 56D8074
MP9 Nameplate, bottom 39B8302

MP10 Headboard PCB 34A8597D

Description

Shure Part

Number

Parts Designations2725C1044 (TK)

Shure UC2 Hand-Held UHF Transmitter

Printed Circuit Board Replacement Parts

Reference

Designation

C314 Capacitor, trim, 5 – 40 pF 152F03
C510 Capacitor, trim, 1 – 3 pF 152A04
D201 Diode, signal / switching, SMD, SOT-23, 1.1 V 184A08
D203 LED, red 184A18
D204 LED, yellow 184B18
D205 LED, green 184C18

D301–304 Diode, dual switching, SOT-23, 1 V 184A07

D501 Diode, rf tuning 184A36

J200 Connector, receptacle, 11-pin header, female 170A08
J205 Socket, strip 170C15
J300 Connector, 11-pin header, male 170A07

L1 Bead, ferrite 162A12

L200,203,207,

300,32,303,306

L304 Inductor, 8.2 nH 162W10
L305 Inductor, 3.3 nH 162T10
L307 Inductor, 22 nH 162D10
L308 Inductor, 6.8 nH 162V10

L501,503 Inductor, 100 nH 162A25

L502 Inductor, 10 nH 162N25

Q3,201,211,212,

213

Q202 Transistor, chopper, PNP, SOT-23 183A07

Q203,303,305 Transistor, SMD, power MOSFET 183A46

Q204,208,209,

210,220

Q301 Transistor 183A01

Q302,501,502 Transistor 183A48

R207 Potentiometer, Gain 46H8014
R320 Potentiometer, Trim, 1 k 146B02

S200 Switch, slide, DPDT 55A178

U5 Detector, SMD voltage 188C210

U107,108, 109 Filter, low-pass 162A28

U311 IC voltage regulator, 5V 188A115

U200,201 IC, quad op amp 188A49

U202 IC, compandor, low voltage 188A126

U203,311 IC voltage regulator, 5 V 188A115

U205 IC, comparator, quad, ultra-low power 188A123
U303 Microprocessor, programmed 188D238G
U304 PLL frequency synthesizer 188A265
U306 Amplifier, operational, dual, SMD 188A118
U501 Dielectric resonator 140A14

Y200 Tonekey Crystal, 32.768 kHz 40A8010

Y301,302 Crystal, 4.0 MHz 40A8012

Inductor, 180 nH 162R10

Transistor, SMD, SOT–23, FET, TMOS 183A30

Transistor, SOT-23, NPN 183A02

Table 5

Description

Shure Part

Number

Replacement Parts and Drawings

28

25C1044 (TK)

Shure UC2 Hand-Held UHF Transmitter

Table 6

Group Designators

(in order by frequency)

Frequency

Range

(MHz)

774–782 Netherlands MC – 1.0 – – – –
782–806 U. S. & Canada UA 1.0 – – – – –
692–716 U.S. UB – – – – – 1.0
797–806 Japan JA – – 1.0 – – –
800–830 Europe MB/MD – 1.0 – – – –
806–810 Japan JB – – – 1.0 – –
838–862 England KK – – – – 1.0 –

Country

Code

MC – – – 1.0 – – – – – –

UA – – 1.0 – – – – – – –
UB – – – – – – – 1.0 – –

JA – – – – 1.0 – – – – –

MB/MD – – – 1.0 – – – – – –

JB – – – – – 1.0 – – – –

KK – – – – – – 1.0 – – –

Country

Designation

R28ΩR29ΩR30kΩR31kΩR32kΩR33kΩR34kΩR35kΩR36ΩR37

Country

Code

R19kΩR20kΩR21kΩR22kΩR26kΩR27

kΩ

Ω

Table 7

U302 EEPROM Programed

Part Numbers

Country

Code

UA 188UCT131UA

UB 188UCT131UB
MB 188UCT131MB
MC 188UCT131MC
MD 188UCT131MD

JA 188UCT131JA
JB 188UCT131JB

KK 188UCT131KK

U102

Part Number

Parts Designations2925C1044 (TK)

Shure UC2 Hand-Held UHF Transmitter

Frequency Dependent Parts

Table 7

(in order by frequency)

Frequency

Range (MHz)

774–782 Netherlands MC .047 0.1 220 2.2 – – – 27
782–806 U. S. & Canada UA – – – – .047 – – 27
692–716 U. S. UB – – – – .047 – n/a n/a
797–806 Japan JA .047 0.1 220 2.2 – – 10 4.7
800–830 Europe MB/MD .047 0.1 220 2.2 – – – 27
806–810 Japan JB – – – – .047 – 10 4.7
838–862 England KK .047 0.1 220 2.2 – – – 27

Country

Code

MC 4.7 4.7 4.7 1.0 – – 183A01 183A02 249 10.0

MB/MD 4.7 4.7 4.7 1.0 – – 183A01 183A02 249 10.0

Country

Code

MC 1.5 10.0 4.02 10.0 100 1.0 10.0 22.1 1.0 – –

MB/MD 1.5 10.0 4.02 10.0 100 1.0 10.0 22.1 1.0 – –

Country

Designation

C505pFC506pFC507pFC509

UA 4.7 4.7 4.7 1.0 – 162A12 – – – –
UB 4.7 6.8 6.8 2.2 – 162A12 – – – –

JA 4.7 4.7 4.7 1.0 95A8278 – 183A01 183A02 249 10.0

JB 4.7 4.7 4.7 1.0 95A8278 162A12 – – – –

KK 3.9 2.2 3.9 – – – 183A01 183A02 249 10.0

R3kΩR6kΩR7kΩR8kΩR9kΩR10MΩR11kΩR12kΩR13MΩR16kΩR40

UA 0 – – – – – – – – 0 –
UB 0 – – – – – – – – 0 –

JA 1.5 4.02 4.02 4.02 100 1.0 10.0 22.1 1.0 – 146B02

JB 0 10.0 – – – – – – – 0 146B02

KK 1.5 10.0 4.02 10.0 100 1.0 10.0 22.1 1.0 – –

Country

Code

C4uFC24uFC35pFC210uFC211uFC254uFC330pFC345

pF

J2 L2 Q1 Q2

R1kΩR2

pF

kΩ

kΩ

Country

Code

MC – 15 24.9 200 0 – 1.0 155A11 155B11 188A136

UA – 15 24.9 200 10.0 4.02 1.0 155A11 155B11 –
UB – 1.5 24.9 200 10.0 4.02 1.0 155A11 155B11 –
JA 100 20 – 24.9 0 – 2.49 155B11 155A11 188A136

MB/MD – 15 24.9 200 0 – 1.0 155A11 155B11 188A136

JB 100 20 – 24.9 10.0 4.02 2.49 155A11 155B11 –
KK – 15 24.9 200 0 – 1.0 155A11 155B11 188A136

R42kΩR233kΩR264kΩR265kΩR287kΩR289kΩR333kΩS301CHS302

Replacement Parts and Drawings

30

GRP

25C1044 (TK)

U2

Shure UC2 Hand-Held UHF Transmitter

Printed Circuit Board, Side 1

UC2 Hand-Held UHF Transmitter

Parts Designations3125C1044 (TK)

Shure UC2 Hand-Held UHF Transmitter

Replacement Parts and Drawings

32

Printed Circuit Board, Side 2

UC2 Hand-Held UHF Transmitter

25C1044 (TK)

Shure UC2 Hand-Held UHF Transmitter

Version K

Printed Circuit Board, Side 1

UC2 Hand-Held UHF Transmitter

Parts Designations3325C1044 (TK)

Shure UC2 Hand-Held UHF Transmitter

Version K

Printed Circuit Board, Side 1

UC2 Hand-Held UHF Transmitter

Replacement Parts and Drawings

34

25C1044 (TK)