Operation Description

FCC ID: DD4UC2B

Operational Description

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FCCID_47417

Description: UC2 Hand-Held UHF Transmitter with SM58, Beta DRWG. UC2-7
58, SM87, or Beta 87. (97-480, 97-481, 98-415, 98-416)
Refer To Drawing NOS. 6A250, 90-8763-11, 90-8763-3, 34-8579, 900G000
Page 1 of 19

Shure Model UC2B (58, 87, B58, B87)
UHF Handheld Transmitter Specification

Outline

General Product Description
I Special Features
II Circuit Description
III Test Equipment
IV Alignment Procedure
V Test for Product Acceptance
VI Agency Approvals
VII Additional Product Specifications
VIII Mechanical Specification
IX Environmental Specification
X Service Evaluation

General Product Description

The Shure Model UC2 is a UHF, µP (microprocessor) controlled, transmitter
operating over the Domestic frequency range of 692 to 716 MHz (With four
different models). The transmitter features adjustable groups/channels, a
battery status indicator, a plastic enclosure, and utilizes an internal antenna
to provide optimum range. This product is intended for use in installed sound,
music instrument,audio/video, audio rental, and touring sound markets.

I Special Features

1. Frequency agility, microprocessor controlled. User capable of
selecting 10 groups of 16 compatible channels each, within the
782-806 MHz frequency band. This allows for a maximum of 160
selectable frequencies. There are 6 different models available
from 692-716 MHz.
2. A minimum of 12 compatible systems (Country dependent).
3. Tone-key squelch.
4. Electrical reverse battery protection.
5. Supports SM58, SM87, BETA58A, and BETA87 cartridges.
6. 8 hour minimum battery life for a new 9V alkaline battery.
7. Rugged, plastic construction.
8. Power On/Off two position miniature switch located on the handle
bezel.
9. Group/Channel rotary switches located on handle under the cup.
10. Three LED battery fuel gauge.
ISS RECORD OF CHANGES MADE EXP. DWG. NO. 16914
1. Production Release
2 ECO 81440: Revised thru-out SHURE BROTHERS INC.
for typos. No spec changes 222 HARTREY AVENUE
3 ECO 81498: Added MC and EVANSTON, IL 60202
PHONE 847-866-2200
MD specifications Microphones-Electronic Components
TYPED S. Grad, D.Cerra, I. Singh

CHECKED

APPROVED K. Mikes

APPROVED

Description: UC2 Hand-Held UHF Transmitter with SM58, Beta DRWG. UC2-7
58, SM87, or Beta 87. (97-480, 97-481, 98-415, 98-416)
Refer To Drawing NOS. 6A250, 90-8763-11, 90-8763-3, 34-8579, 900G000
Page 2 of 19

11. “Greenie” screwdriver adjustable audio gain.

II Circuit Description

Audio Section

Audio enters L200, an inductor used as an RF choke. The signal is ac coupled
through C200 into a user adjustable gain stage. 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 32dB adjustable gain stage is built around U200A. The gain of this stage is
externally controlled by the user. C206, C207, and C208 protect the amplifier
and bias circuits from RF interference. This is a unique stage in that it is
non-inverting, and allows for a gain less than unity.

Audio then enters a buffer to the premphasis network and the compression stage.
R213, R214, and C211 set up two corners for the premphasis network. The purpose
of pre-emphasis is to boost the high frequencies before transmission. This
network feeds an NE575 compandor, U202, which utilizes an external amplifier
U201B. The compandor performs 2:1 logarithmic compression of the audio signal.
Additionally, the pre-emphasis network plays a role in setting the hinge point
(0dB gain) of the compandor. From the compressor, the processed audio enters a
summing amplifier U201C. Here, tone key (and the call ID signal for the JB
Group) is added to the processed audio signal.

Transistors Q208 and Q209 with crystal Y200 form the tone key oscillator circuit
which provides 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; therefore, if the tone key or
the transmitter is turned off, the receiver will be muted. The tone key squelch
will eliminate receiver noise associated with loss of a carrier. Q211 acts as a
switch for toggling the tone key MUTE/UNMUTE and is controlled by the µP. The
tone key signal along with the processed audio signal is then fed to a summing
amplifier U201C. R244, at the output of the summing amplifier, is used to help
prevent spurious oscillations from the opamp. After passing the ac coupling
capacitor, C243, the signal is then fed to the RF module through an RF choke,
L207.

The battery meter circuit is made up of comparator U205, LED’s D203, D204, 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.
ISS RECORD OF CHANGES MADE EXP. DWG. NO. 16914
1. Production Release
2 ECO 81440: Revised thru-out SHURE BROTHERS INC.
for typos. No spec changes 222 HARTREY AVENUE
3 ECO 81498: Added MC and EVANSTON, IL 60202
PHONE 847-866-2200
MD specifications Microphones-Electronic Components
TYPED S. Grad, D.Cerra, I. Singh

CHECKED

APPROVED K. Mikes

APPROVED

Description: UC2 Hand-Held UHF Transmitter with SM58, Beta DRWG. UC2-7
58, SM87, or Beta 87. (97-480, 97-481, 98-415, 98-416)
Refer To Drawing NOS. 6A250, 90-8763-11, 90-8763-3, 34-8579, 900G000
Page 3 of 19

Power to the audio pcb comes from a 9V battery, via switch S200. FET Q203 is
used for electrical reverse battery protection by connecting the negative
battery terminal to the PCB ground, only when the battery is connected with the
correct polarity. The 9v then enters U203, a low dropout 5V regulator, which
gives a clean regulated 5V 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, are used for power management and timing.

RF section

Processed audio enters R320, an internal potentiometer which is adjusted to set
the appropriate deviation for the country in which the system is sold. The
audio is then fed to the tuning voltage line of the voltage controlled
oscillator (VCO), and modulates the carrier directly. The use of a phase locked
loop (PLL) frequency synthesized system eliminates the need for multiplier
stages, resulting in a much higher degree of spectral purity. The VCO is
shielded to prevent external RF fields from affecting its operation. Regulated
5vdc power from the low dropout regulator U311 is provided to ensure frequency
stability with changes in battery voltage.

The VCO is capable of tuning from 782 to 806 MHz(domestic) with a 1 to 4 volt
tuning voltage range. At the output of the VCO, C504, C505, the RF signal
splits into two paths. The output of the VCO is coupled by C323 to the
frequency control 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, which is adjusted by means of trimmer C314. The transmitter output
frequency is user selectable in groups of compatible channels from 782 to 806
MHz. 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 which are integrated by a passive loop
filter R316, C319, R317, C353, R318, and 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.

The VCO output is also coupled to the pre-driver and rf power amplifier through
a resistive network consisting of R322, R324, R325, and a matching network
containing C328, C329, and C330. The pre-driver stage, Q302, provides roughly
6-8 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, and C337 provide
filtering / matching for the stage. The collector of Q302 feeds into the power
amplifier stage via a pi matching network made up of C339, L305, and C340.

ISS RECORD OF CHANGES MADE EXP. DWG. NO. 16914
1. Production Release
2 ECO 81440: Revised thru-out SHURE BROTHERS INC.
for typos. No spec changes 222 HARTREY AVENUE
3 ECO 81498: Added MC and EVANSTON, IL 60202
PHONE 847-866-2200
MD specifications Microphones-Electronic Components
TYPED S. Grad, D.Cerra, I. Singh

CHECKED

APPROVED K. Mikes

APPROVED

Description: UC2 Hand-Held UHF Transmitter with SM58, Beta DRWG. UC2-7
58, SM87, or Beta 87. (97-480, 97-481, 98-415, 98-416)
Refer To Drawing NOS. 6A250, 90-8763-11, 90-8763-3, 34-8579, 900G000
Page 4 of 19

The RF power amplifier Q304 is a dual emitter BJT from HP, namely the HP
AT41486. It is a high-gain, high-frequency, low noise device, capable of
providing +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. For Japanese systems only, the output power is trimmed via R42.
L306 acts as a filter / partial choke, and C349, C350, C355, and C356 provide a
good emitter bypass to ground. The amplifier output is matched to low pass
filter U310 via L307. The low pass filter output couples to the antenna via
C347 and L308. Since the battery is somewhat shorter than it should be, L308
helps to make it look electrically longer, closer to .25 wave lengths.

The transmitter is capable of delivering +17dbm (50 milliwatts) maximum to the
antenna (Domestic). During transmitter power up and frequency selection the RF
power is muted by bringing the gates of Q303/Q305 low. This provides
approximately 45dB RF attenuation until the PLL has locked. The transmitter RF
is then unmuted by bringing the gates Q303/Q305 of high. During transmitter
power off conditions, voltage is first removed from the VCO by bringing the base
of Q301 high. In this manner the carrier signal of the transmitter is not
allowed to drift off frequency during power on / power off conditions.

ETSI Audio Section

An ETSI-approved transmitter uses the same board as the non-ETSI system, except
it requires a different circuit topology and different parts. All board groups,
except the “A” & “D” groups, require an ETSI approved audio section.* A limiter
is inserted between the premphasis and the compressor to limit the occupied
bandwidth. The buffer after the gain stage, U201A, is now an inverter with
premphasis and 20dB of attenuation. Previously bypassed, the expander side of
the NE575 (U202) is now activated and is used as a limiter. A sample of the
audio is taken from the limiter output (U202.6) and sent to a control circuit
which detects signals above a limiting threshold. The comparator then sends a
control signal to U202.5 which clamps the signal.

* For the “C” group (JA), a modified limiter circuit is used which has less
attenuation.

ISS RECORD OF CHANGES MADE EXP. DWG. NO. 16914
1. Production Release
2 ECO 81440: Revised thru-out SHURE BROTHERS INC.
for typos. No spec changes 222 HARTREY AVENUE
3 ECO 81498: Added MC and EVANSTON, IL 60202
PHONE 847-866-2200
MD specifications Microphones-Electronic Components
TYPED S. Grad, D.Cerra, I. Singh

CHECKED

APPROVED K. Mikes

APPROVED

Description: UC2 Hand-Held UHF Transmitter with SM58, Beta DRWG. UC2-7
58, SM87, or Beta 87. (97-480, 97-481, 98-415, 98-416)
Refer To Drawing NOS. 6A250, 90-8763-11, 90-8763-3, 34-8579, 900G000
Page 5 of 19

UHF Hand Held Transmitter Digital Section
LIMITER
CONTROL INPUT

MIC Σ AUDIO
OUT

TONE KEY
LIMITER
+5V CONTROL OUTPUT
REG. +5v
BATTERY CALL ID
TONE KEY MGMT.
CIRCUIT & FUEL
GAUGE

FROM ON / OFF UNREG. PWR.
BATT. TONE CONTROL
SWITCH

PWR. OFF DETECT
EEPROM
FET
BYPASS
PLL CONTROL
MCU (MEM)

PWR.
CONTROL HOLD
CIRCUIT

SYNTH.

GROUP CHANNEL

RF POWER
RF MUTE RF MUTE

AUDIO IN

VCO

Fig. 1
Block Diagram of the Hand Held Transmitter

1.0 General Description

The Digital Section consists of following circuitry blocks:

1.0.0 Microcontroller Section
It consists of U303 microcontroller. The rotary switches indicate the UHF
frequency Group and Channel as indicated in appendix A. 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 U303 microcontroller if the 5 V normal operating
voltage falls below 4.3 V. C302 and C303 form the power supply bypass filter
circuit.

1.0.1 Memory section
It consists of U302, non volatile Electrically Erasable / Programmable Read Only
Memory (EEPROM), that stores the mapping of the compatible groups and channels.
ISS RECORD OF CHANGES MADE EXP. DWG. NO. 16914
1. Production Release
2 ECO 81440: Revised thru-out SHURE BROTHERS INC.
for typos. No spec changes 222 HARTREY AVENUE
3 ECO 81498: Added MC and EVANSTON, IL 60202
PHONE 847-866-2200
MD specifications Microphones-Electronic Components
TYPED S. Grad, D.Cerra, I. Singh

CHECKED

APPROVED K. Mikes

APPROVED

Description: UC2 Hand-Held UHF Transmitter with SM58, Beta DRWG. UC2-7
58, SM87, or Beta 87. (97-480, 97-481, 98-415, 98-416)
Refer To Drawing NOS. 6A250, 90-8763-11, 90-8763-3, 34-8579, 900G000
Page 8 of 19

1.2.5 Append the single line data text to “filename<space>revision<LF>” header.
Revision can be variable length numeric revision indicator with a decimal point
and a single decimal digit after it (e.g. 1.0 or 1.1). Where filename shall be 8
characters max. and may have only valid names as tabulated below. Revision may
or may not match the microcontroller revision level. This file must have “.txt”
extension. The header in the file, as described above, is for version control by
Automated Test Equipment (ATE) only. The programmer must not send this header to
the EEPROM.

FILENAME COUNTRY
ucuafram USA
ucjbfram Japan
ucmafram Europe-I
uckafram U.K.
Table 2

Following is an example how a ucuafram.txt, software release 1.0, may look like:
ucuafram 1.0
080F170817171615151414100D0A0A0909090A0B0C0C0D0D0E0F11111213141409090A0B0B0C0D0D
0E0F1112131314140909090B0C0D0D0E0F0F1011111213140C0D0D0E0F0F11121313141515161616
090A0A0B0B101112121314151516161709090A0A0B0C0D0D0E0F1414151616170809090A0B0C0C0D
0D0D0F10111112130909090B0C0D0D0E0F0F1011111213140C0D0D0E0F0F11121313141515161616
35002B303008203810280038302800180E272D10022A0330130A0220210E0A1E1D3619062425033A
1823342B09360F37091D3B011B0D2B1D23373307253A3137340835130A2834300E36140B240C2A3E
090A2D1F3D15020321220F1F3311390D1D361E3C333E263F312D1428060C2508351831230B022F08
2B3F2315112F3518091D3B011B0D2B1D23373307253A3137340835130A2834300E36140B240C2A3E
FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF
FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF
FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF
FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF
FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF

1.2.6 General description of EEPROM contents
There are several parameters that describe the transmitter and two of them are
stored in the EEPROM, namely, N offset and A. The Group and Channel setting is
simply an address of N offset. The address of A values stored in the EEPROM is
simply = [160 + N offset address]. Being a frequency agile system it tunes to an
EEPROM defined frequency by sending appropriate variables to the Phase Locked
Loop (PLL) frequency synthesizer, U104. The mathematical relationship between
these variables and the synthesized frequency is as below:

FVCO = (P*N+A)*FOSC/R eqn. 1

1.2.6.0 Where FVCO in equation 1 above is the output frequency of external
Voltage Controlled Oscillator (VCO). This is the carrier frequency upon which

ISS RECORD OF CHANGES MADE EXP. DWG. NO. 16914
1. Production Release
2 ECO 81440: Revised thru-out SHURE BROTHERS INC.
for typos. No spec changes 222 HARTREY AVENUE
3 ECO 81498: Added MC and EVANSTON, IL 60202
PHONE 847-866-2200
MD specifications Microphones-Electronic Components
TYPED S. Grad, D.Cerra, I. Singh

CHECKED

APPROVED K. Mikes

APPROVED

Description: UC2 Hand-Held UHF Transmitter with SM58, Beta DRWG. UC2-7
58, SM87, or Beta 87. (97-480, 97-481, 98-415, 98-416)
Refer To Drawing NOS. 6A250, 90-8763-11, 90-8763-3, 34-8579, 900G000
Page 9 of 19

the audio signal is FM modulated.

1.2.6.1 FOSC in equation 1 above is the output frequency of an external
reference oscillator. It is 4 Mhz, Y101, for this system and is reference
frequency for the Phase Lock Loop synthesizer.

1.2.6.2 P, or preset modulus of external dual modulus prescaler, can be 64
or 128 but has been defined as a constant in the microcontroller software as 64.

1.2.6.3 N, or preset divide ratio of binary 11-bit counter, can have values
from 16 to 2047. The lowest N value is a constant, equal to 480, and is defined
in the microcontroller program. Thus the minimum tuneable frequency limited by
the current microcontroller software is 768.000 Mhz. All mapped frequencies,
according to a compatible table, have their N offsets stored from address 000 up
to 09F16. Therefore, the highest tunable frequency limited by the microcntroller
software and 8 bit EEPROM data is 1177.600 Mhz. The maximum number of
frequencies can not exceed 160 (up to address 15916) due to hardware limitations.

1.2.6.4 A, or preset divide ratio of binary 7-bit swallow counter, can
have values from 0 up to and including 127. However, value of A can not exceed
the value of N in general. For this system the highest value of A is 63. All
frequencies have their respective A values stored from address 0A016 up to
address 13F16. The maximum number of mapped frequencies is limited to 160 due to
hardware limitations.

1.2.6.5 R, or the preset divide ratio of binary 14-bit programmable
reference counter. It can have any value from 6 to 16383, however, given a fixed
frequency step size of 0.025 Khz (or multiples thereof) and FOSC of 4 MHz for the
value of R is also a constant defined in the software. R is simply a ratio of
FOSC (4 MHz) to the frequency step size (0.025 Khz) and thus equal to 160 for
this system.

1.2.6.6 Following is the memory map of U302 EEPROM corresponding to an
above example of u1uafram.txt:

ADDRESS16 DATA16 COMMENTS FREQ. GROUP CHAN
000 08 N offset 782.125 0 0
001 0F N offset 792.000 0 1
... ... N offset ... 0 ...
010 09 N offset 782.750 1 0
... ... N offset ... ... ...
020 09 N offset 783.125 2 0
... ... N offset ... ... ...
09F 16 N offset 804.750 9 15
0A0 35 A 782.125 0 0
0A1 00 A 792.000 0 1

ISS RECORD OF CHANGES MADE EXP. DWG. NO. 16914
1. Production Release
2 ECO 81440: Revised thru-out SHURE BROTHERS INC.
for typos. No spec changes 222 HARTREY AVENUE
3 ECO 81498: Added MC and EVANSTON, IL 60202
PHONE 847-866-2200
MD specifications Microphones-Electronic Components
TYPED S. Grad, D.Cerra, I. Singh

CHECKED

APPROVED K. Mikes

APPROVED

Description: UC2 Hand-Held UHF Transmitter with SM58, Beta DRWG. UC2-7
58, SM87, or Beta 87. (97-480, 97-481, 98-415, 98-416)
Refer To Drawing NOS. 6A250, 90-8763-11, 90-8763-3, 34-8579, 900G000
Page 10 of 19

... ... A ... 0 ...
0B0 0E A 782.750 1 0
... ... A ... ... ...
0C0 1D A 783.125 2 0
... ... A ... ... ...
13F 3E A 804.750 9 15
140 FF Not used
... ... Not used
1FF FF Not used

1.3 After the EEPROM is programmed the system is capable of all designed
functions and the system level functional tests can be conducted.
Following are the initial conditions for system functional tests:

1.3.0 Power switch must be in off position.

1.3.1 Audio and RF / Digital boards must be electrically connected.

1.3.2 All voltage measurements are w.r.t. TPGND1 (RF ground) unless specified
otherwise.

1.3.3 Logic high shall imply 5 Vdc ± 5 %.

1.3.4 Logic low shall imply 0.0 Vdc ± 20 mVdc.

1.3.5 Apply +9 Vdc ± 1 % to TP102 (DVBATT+) w.r.t. TP104 (DVBATT-). The power
supply current drain must be less than 0.500 µA dc.

1.4 Operational description and troubleshooting guide

1.4.0 All of the above initial conditions must be established unless stated
otherwise.

III Test Equipment or Equivalent

1.0 Spectrum analyzer HP8591E
1.1 Digital multimeter Fluke 87
1.2 Distortion Analyzer/ac-dc meter/audio osc. HP 8903B
1.3 Frequency Counter HP 5385A
1.4 Receiver Shure U4S/D or UC4
1.5 50 ohm, RG-174 BNC to open (stripped) coaxial cable
1.6 For JA/JB, 50 ohm, “Rocket Launch” to BNC cable.

IV Alignment Procedure
ISS RECORD OF CHANGES MADE EXP. DWG. NO. 16914
1. Production Release
2 ECO 81440: Revised thru-out SHURE BROTHERS INC.
for typos. No spec changes 222 HARTREY AVENUE
3 ECO 81498: Added MC and EVANSTON, IL 60202
PHONE 847-866-2200
MD specifications Microphones-Electronic Components
TYPED S. Grad, D.Cerra, I. Singh

CHECKED

APPROVED K. Mikes

APPROVED

Description: UC2 Hand-Held UHF Transmitter with SM58, Beta DRWG. UC2-7
58, SM87, or Beta 87. (97-480, 97-481, 98-415, 98-416)
Refer To Drawing NOS. 6A250, 90-8763-11, 90-8763-3, 34-8579, 900G000
Page 11 of 19

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

dB Conversion Chart
0dBV = 2.2 dBu
0dBu = 0dBm assuming the load = 600 ohms

Be aware that dBu is a measure of voltage and
dBm is a measure of power. The HP8903, for
example, should be labeled dBu instead of dBm
since it is a voltage measurement. These two
terms are often used interchangeably even though
they have different meanings.

The alignment procedure is sequential and does not change unless specified.
Use RG58 or any other low loss, 50 ohms cables for all RF connections. Keep
test cables as short as possible. Include the insertion loss of the cables and
the connectors for all RF measurements. DC voltages are present at most RF
test points. Use DC blocks to protect the test equipment, if necessary. All
audio analyzer filters should be OFF unless otherwise specified.

Initial Setup

1.0 Connect the audio board to rf board through interconnects J200 and J300.
1.1 Apply +9V across the battery terminals, J201 and J202.
1.2 Set audio gain pot, R207, to minimum.
1.3 For bench testing, remove, C347 and connect a 50Ω cable between
TPRF1/ground and a frequency counter. For JA/JB, connect the “Rocket
Launch” cable from J2 to the frequency counter.
1.4 Connect audio generator to TPA1. For bench testing, the audio generator
can be directly connected to the headboard gold contacts with clip
leads.
1.5 Turn on UC2 by toggling the power switch, S200.
1.6 Set the UC2 Group and Channel switches, S301 and S302, according to the
group designators on the board and the following table.

ISS RECORD OF CHANGES MADE EXP. DWG. NO. 16914
1. Production Release
2 ECO 81440: Revised thru-out SHURE BROTHERS INC.
for typos. No spec changes 222 HARTREY AVENUE
3 ECO 81498: Added MC and EVANSTON, IL 60202
PHONE 847-866-2200
MD specifications Microphones-Electronic Components
TYPED S. Grad, D.Cerra, I. Singh

CHECKED

APPROVED K. Mikes

APPROVED

Description: UC2 Hand-Held UHF Transmitter with SM58, Beta DRWG. UC2-7
58, SM87, or Beta 87. (97-480, 97-481, 98-415, 98-416)
Refer To Drawing NOS. 6A250, 90-8763-11, 90-8763-3, 34-8579, 900G000
Page 12 of 19

Table 1

Group Channel Carrier Tuning
Group Group Switch Switch Frequency Voltage Deviation
Code (S302) (S301) (MHz) TP30 (Vdc) (kHz)
UA A 4 0 805.500 3.7 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 5 857.125 2.9 15
MC B 1 1 774.125 1.3 ± .25 15
MD B 3 7 805.500 2.2 15
UB F not defined not defined -- -- 45

* For JA only, the “Group” switch has 16 positions, and the “Channel”
switch has 10 positions.

Tuning Voltage / Frequency Alignment

2.0 Put a dc voltmeter across TP30 (tuning voltage line) and RFGND.
2.1 Adjust the VCO trimmer C510 until the voltmeter reading matches the
appropriate entry in Table 1, +/- 0.125 V.
2.2 Adjust the variable capacitor C314 until the frequency counter
measurement matches the appropriate entry in table 1, ± 1kHz.

Deviation Adjustment

The following procedure requires a U4S or D, or a UC4 receiver and is designed
to tune the UC 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.

3.0 Receiver Setup
3.0.1 Connect the RF signal generator to one of the receiver antenna
ports.
3.0.2 Set the receiver frequency to match the transmitter.
3.0.3 Set the rf signal generator frequency to match the transmitter.
3.0.4 Set the deviation according to Table 1.
3.0.5 Modulate the rf signal with a 1kHz audio tone.
3.0.6 Turn the receiver on and set the tone key switch (S501 for UC4,
S201 for U4S) to the OFF position.
3.0.7 Connect the ac voltmeter to the unbalanced output of the receiver.
3.0.8 Note the voltage obtained. This is the deviation reference
voltage.
3.0.9 Disconnect the RF generator from the receiver and return the tone
ISS RECORD OF CHANGES MADE EXP. DWG. NO. 16914
1. Production Release
2 ECO 81440: Revised thru-out SHURE BROTHERS INC.
for typos. No spec changes 222 HARTREY AVENUE
3 ECO 81498: Added MC and EVANSTON, IL 60202
PHONE 847-866-2200
MD specifications Microphones-Electronic Components
TYPED S. Grad, D.Cerra, I. Singh

CHECKED

APPROVED K. Mikes

APPROVED

Description: UC2 Hand-Held UHF Transmitter with SM58, Beta DRWG. UC2-7
58, SM87, or Beta 87. (97-480, 97-481, 98-415, 98-416)
Refer To Drawing NOS. 6A250, 90-8763-11, 90-8763-3, 34-8579, 900G000
Page 13 of 19

key switch to the ON position.
3.1 Connect the audio generator to the mic input of the transmitter and set
the generator frequency to 1kHz.
3.2 Domestic (UA,UB): Adjust audio input level to give -6.8 dBu ± 0.02
dB (354mV ± 1mV) at TPA4 (U201.7).
Japan (JA & JB): Adjust audio input level to give -23.47dBu (52mV ±
1mV) at TPA4.
Europe(MB,MC,MD): Adjust audio input level to give -16.3 dBu (118mV ±
1mV) at TPA4.
England (KK): Adjust audio input level to give -15.3 dBu (133mV
± 1mV)at TPA4.
3.3 Transmit from the UC2 transmitter to the receiver. If transmission is
conductive instead of radiative, insert a 20-60 dB pad between the
transmitter rf output and the receiver rf input. Turn the transmitter
ON and adjust R320 until the ac voltmeter on the receiver reads the
deviation reference voltage ± 0.1 dB, as measured in 3.0.7.
3.4 Disconnect the audio generator.

V Test for Product Acceptance

1.0 Initial Setup
Connect the (+) terminal of the power supply through a
milliammeter to the positive battery terminal and the (-) terminal
to the negative battery terminal. Connect a DC Voltmeter across
the power supply. Connect the audio generator to the center
spring contact on the headboard and ground. Connect the RMS audio
voltmeter across pin-8 U201D and GND. Connect the audio distortion
analyzer between “AUD_OUT” (input to RF section) and GND.

2.0 Reverse Battery Protection Test
Turn on the power supply and adjust to -9.0V ± 0.1V as indicated
on the DC voltmeter. Measure the current drain on the
milliammeter. The current should be less than 0.5 mA.

3.0 Voltage Regulation Check
With power applied properly, and the unit switched on, measure the
dc voltage at C308 pin 1 (RF board) and at TP5 (C227 pin 1 on the
audio board). They should be 5 ± 0.2 Volts.

4.0 Current Consumption Test
With +9V to the battery terminals, measure the current drain using
a DC milliameter. It should be 60 +/- 10 mA.

5.0 Frequency Response Test
ISS RECORD OF CHANGES MADE EXP. DWG. NO. 16914
1. Production Release
2 ECO 81440: Revised thru-out SHURE BROTHERS INC.
for typos. No spec changes 222 HARTREY AVENUE
3 ECO 81498: Added MC and EVANSTON, IL 60202
PHONE 847-866-2200
MD specifications Microphones-Electronic Components
TYPED S. Grad, D.Cerra, I. Singh

CHECKED

APPROVED K. Mikes

APPROVED

Description: UC2 Hand-Held UHF Transmitter with SM58, Beta DRWG. UC2-7
58, SM87, or Beta 87. (97-480, 97-481, 98-415, 98-416)
Refer To Drawing NOS. 6A250, 90-8763-11, 90-8763-3, 34-8579, 900G000
Page 15 of 19

- Measure the 32.768kHz tone key level to be 22dBc ± 2dB.
- For JA/JB, measure the tone key level to be -25 dBc +/- 2 dB.

VI Agency Approvals

1.0 FCC (UA,UB)
2.0 IC (UA)
3.0 ETS (MB,MC,MD,KK)
4.0 MKK (JA,JB)

VII Additional Product Specifications
UA Model
SPECIFICATION
Operating Frequency 782.125 to 805.875 MHz
Number of User Selectable Channels 160 (25 kHz Spacing)
Type of Emission 120KF3E
Oscillator PLL Controlled Synthesizer
RF Conductive Power Output 16dBm +1 /-2dBm
Tone Key Signal 32.786 kHz
Maximum FM Deviation 45 kHz
Dynamic Range > 100dB
Total Harmonic Distortion < 0.7% (45kHz deviation, 1kHz)
Audio Adjustment Range -6 to 26dB, user adjustment
Operating Voltage 9V (Alkaline recommended)
Power Consumption 60mA ± 10mA @ 9V
Battery Life 8 hrs (Alkaline Batteries)

MB Model (Changes from UA model)
Operating Frequency 800.100 to 829.700 MHz
Number of User Selectable Channels 160 (25 kHz Spacing)
Dynamic Range > 80dB

MC Model (Changes from UA model)
Operating Frequency 774.000 to 782.000 MHz
Number of User Selectable Channels 160(25 kHz Spacing)
Dynamic Range > 80dB

MD Model (Changes from UA model)
Operating Frequency 800.000 to 820.000 MHz
Number of User Selectable Channels 160(25 kHz Spacing)
Dynamic Range > 80dB
ISS RECORD OF CHANGES MADE EXP. DWG. NO. 16914
1. Production Release
2 ECO 81440: Revised thru-out SHURE BROTHERS INC.
for typos. No spec changes 222 HARTREY AVENUE
3 ECO 81498: Added MC and EVANSTON, IL 60202
PHONE 847-866-2200
MD specifications Microphones-Electronic Components
TYPED S. Grad, D.Cerra, I. Singh

CHECKED

APPROVED K. Mikes

APPROVED

Description: UC2 Hand-Held UHF Transmitter with SM58, Beta DRWG. UC2-7
58, SM87, or Beta 87. (97-480, 97-481, 98-415, 98-416)
Refer To Drawing NOS. 6A250, 90-8763-11, 90-8763-3, 34-8579, 900G000
Page 16 of 19

JA Model (Changes from UA model)
Operating Frequency 797.125 to 805.875 MHz
Number of User Selectable Channels 85 (125 kHz Spacing)
Dynamic Range > 80dB
Frequency Stability ± 20 ppm
Reference FM Deviation 5 kHz
1kHz audio level -23.47dBu (52mV) at TPA4
Output Power + 8.8 dBm +/- .5 dB (power
meter verification required)

JB Model (Changes from UA model)
Operating Frequency 806.125 to 809.750 MHz
Number of User Selectable Channels 30 (125 kHz Spacing)
Dynamic Range > 100dB
Frequency Stability ± 20 ppm
Reference FM Deviation 5 kHz
1kHz audio level -23.47dBu (52mV) at TPA4
Output Power + 8.8 dBm +/- .5 dB (power
meter verification required)

KK Model (Changes from UA model)
Operating Frequency 838.625 to 861.875 Mhz
Output power +14 dBm +1/-2 dB
Dynamic Range > 80dB
Number of User Selectable Channels 140 (25 kHz Spacing)

See Drawing #900G000 for the detailed frequency maps for each country.

VIII Mechanical Specification

1. Overall Dimensions
254mm x 51mm DIA. (10 x 2 IN) including SM58 cartridge.
2. Weight
375.6 grams(13.25 oz), without battery
3. Housing
Molded ABS Handle and battery cup
5. Battery
9V battery type MN1604, Alkiline recommended

IX Environmental Specification
ISS RECORD OF CHANGES MADE EXP. DWG. NO. 16914
1. Production Release
2 ECO 81440: Revised thru-out SHURE BROTHERS INC.
for typos. No spec changes 222 HARTREY AVENUE
3 ECO 81498: Added MC and EVANSTON, IL 60202
PHONE 847-866-2200
MD specifications Microphones-Electronic Components
TYPED S. Grad, D.Cerra, I. Singh

CHECKED

APPROVED K. Mikes

APPROVED

Description: UC2 Hand-Held UHF Transmitter with SM58, Beta DRWG. UC2-7
58, SM87, or Beta 87. (97-480, 97-481, 98-415, 98-416)
Refer To Drawing NOS. 6A250, 90-8763-11, 90-8763-3, 34-8579, 900G000
Page 17 of 19

Temperature Storage
7 days at +165F (+74C) degrees, unpackaged.
7 days at -20F (-29C) degrees, packaged.
After each 7 day storage, the units must be allowed to stabilize for 24
hours before testing. Units must operate per Section V.

Temperature Cycling
5 cycles from -20F (-29C) degrees, to +165 (+74C) degrees, allow 24
hours for stabilization before testing. Units must operate per Section V
specifications Mechanically and Electrically.

Operational Temperature
Operate units as described in Section V at +20F (-7C) and +120F (+49C)
degrees. Allow three hours for stabilization of each temperature before
testing. Units must operate per Section V specifications.

Steady State Humidity
Perform a 10 day test at 90% RH at room temperature. Evaluate units for
visual and mechanical defects after 1, 3, 5, 7, and 10 days. At the end
of the 10 day period allow the units to recover for 24 hours. Units must
pass Section V specifications.

Operational Humidity
Operate units as described in Section V at 90% RH at room temperature.
Allow two days for stabilization.

Moisture Resistance
Perform a 7 day test at 90% to 98% RH with temperature cycled between +14F
(-10C) and +150F (+65C) degrees. Allow the units to recover for 24
hours. Product must meet Section V specifications.

Mechanical Shock
Hand Held Drop Test: Drop product from a height of 6’ onto a hardwood
floor for a total of 10 drops. The unit must pass Section V
specifications.
Stand Drop Test: Place product on a stand with the appropriate size
swivel adapter. Drop unit from a height of 5’ onto a hardwood floor
for total of 10 drops. The product must meet Section V specifications.

Electrostatic Discharge
Product will be subjected up to a ± 15 kV air discharge and ± 4 kV contact
discharge. Units must operate per Section V specifications.

X Service Evaluation

1.0 DC PROBLEMS (RF Section)
ISS RECORD OF CHANGES MADE EXP. DWG. NO. 16914
1. Production Release
2 ECO 81440: Revised thru-out SHURE BROTHERS INC.
for typos. No spec changes 222 HARTREY AVENUE
3 ECO 81498: Added MC and EVANSTON, IL 60202
PHONE 847-866-2200
MD specifications Microphones-Electronic Components
TYPED S. Grad, D.Cerra, I. Singh

CHECKED

APPROVED K. Mikes

APPROVED

Description: UC2 Hand-Held UHF Transmitter with SM58, Beta DRWG. UC2-7
58, SM87, or Beta 87. (97-480, 97-481, 98-415, 98-416)
Refer To Drawing NOS. 6A250, 90-8763-11, 90-8763-3, 34-8579, 900G000
Page 18 of 19

1.1 Verify the battery voltage is between 6 and 9v. Check for proper
Vcc and +5v RF at Q301 (make all DC measurements with respect to
RF Ground unless otherwise specified). If incorrect voltage is
present check the biasing resistors values. Trace the DC back to
the voltage regulator. Check the power switch. Look for open
coils, cracked parts, reversed polarity capacitors, solder shorts.
If you have a short to ground from 5 volts try to isolate
different parts of the circuit.

1.2 Verify :

- RF OFF signal changes from +5v at power up and power down to
0v during normal operation. Trace signal to uP. Q301 should
be saturated during normal operation.

- Battery voltage appears at U311 pin 6. Check for reversed
polarity capacitors C308 and C309. Check for open coil L300.
Make sure J300 is soldered correctly.

2.0 RF FREQUENCY PROBLEMS

2.1 If the carrier is out of spec. by less then 40kHz and can’t be
corrected by adjusting C314, check the values of C314, C313 & Y302.
If these values are correct replace C314. As a last resort replace
the synthesizer U304.

2.2 If the carrier frequency is not between 782 and 810 MHz, or is
unstable, the loop is unlocked. Check the solder connections at
the, head board, VCO , µP (traces LE, D, & CK) and synthesizer
U304. Check for 4MHz oscillation at pins 1&2 of U304. If not
replace the crystal Y302. Check the values and polarity of the
loop filter: R316, C319, R317, C353, R318, C320, C354, U306B,
R319, R320, R321. Check the bias voltage of U304 pins 3 & 4 and
U306B pin 8. As a last resort replace the synthesizer U304. The
tuning voltage of the VCO should be about 2.9 volts DC when the
transmitter is set for 796 MHz operation (1,C for UA).

3.0 LOW RF OUTPUT POWER

3.1 Check the polarity of the low pass filter U1 (RF IN is marked with
a dot).
3.3 Check the polarity of Q304.
3.4 Check for missing ground connections.
3.5 Verify VCO output power.
3.5.1 Check DC level at VCO Vcc pin (L302).
3.5.2 Partially isolate the VCO from the rest of the circuit by removing
ISS RECORD OF CHANGES MADE EXP. DWG. NO. 16914
1. Production Release
2 ECO 81440: Revised thru-out SHURE BROTHERS INC.
for typos. No spec changes 222 HARTREY AVENUE
3 ECO 81498: Added MC and EVANSTON, IL 60202
PHONE 847-866-2200
MD specifications Microphones-Electronic Components
TYPED S. Grad, D.Cerra, I. Singh

CHECKED

APPROVED K. Mikes

APPROVED

Description: UC2 Hand-Held UHF Transmitter with SM58, Beta DRWG. UC2-7
58, SM87, or Beta 87. (97-480, 97-481, 98-415, 98-416)
Refer To Drawing NOS. 6A250, 90-8763-11, 90-8763-3, 34-8579, 900G000
Page 19 of 19

C323. The Carrier frequency will no longer be locked, but the
output power from the VCO should be around -1 dBm into a 50 Ohm
load, at some frequency. If you don’t see any carrier, try
adjusting C510.
3.5.3 If the power out of the VCO is still low the problem is in the
VCO.
3.6.1 Check the values of R322, R323, R324, R325, and C329.
3.7 Verify DC bias of Q302 and Q304. Verify that the RF Mute signal
changes from 0v at power up and power down to +5v during normal
operation. If Q303 & Q305 are not in a low impedance state during
normal operation the RF power at the antenna port will be
attenuated by about 45dB.
3.8 Isolate components starting from the antenna and working back to
the RF power amp.
3.8.3 Remove the lowpass filter and check the power out of the amplifier
at C345.
3.8.4 Check the values of the input and out put matching networks for
Q302, Q304 (C329, L304, C338, L305, C339, C340, L306, and L307).
Also, look for open coils.
3.8.5 Check the values of bypass capacitors C357, C2, C332, C333, C334,
C335, C360, C341, C342, C349, C350, C355, C356.
3.8.6 As a last resort replace Q302 or Q304.

4.0 EXCESSIVE CURRENT DRAIN

Try isolating different sections of the circuit, RF, Audio,
Digital, etc. Look for reversed polarity capacitors, wrong
resistor values, or solder shorts to ground.

5.0 DEVIATION PROBLEMS

If R320 can’t be adjusted to obtain 45 kHz deviation, try to
isolate the problem to the Audio or RF section. Check the value
of R319 and R320. To check the RF section, set the transmitter
frequency to 796 MHz (1,C for UA) and verify the tuning voltage of
the VCO is approximately 2.9 V DC. To check audio section, apply
-5 dBu at 1 kHz to mic input. Set the gain to minimum. Check for
audio with a scope at “AUDIO_OUT” (L207). The level should be
approximately -9.9 dBu. If there is no audio, or the level is
wrong, the problem is probably in the audio section. Trace
backwards through the audio stages until you find the problem.

ISS RECORD OF CHANGES MADE EXP. DWG. NO. 16914
1. Production Release
2 ECO 81440: Revised thru-out SHURE BROTHERS INC.
for typos. No spec changes 222 HARTREY AVENUE
3 ECO 81498: Added MC and EVANSTON, IL 60202
PHONE 847-866-2200
MD specifications Microphones-Electronic Components
TYPED S. Grad, D.Cerra, I. Singh

CHECKED

APPROVED K. Mikes

APPROVED

Description: UC2 Hand-Held UHF Transmitter with SM58, Beta DRWG. UC2-7
58, SM87, or Beta 87. (97-480, 97-481, 98-415, 98-416)
Refer To Drawing NOS. 6A250, 90-8763-11, 90-8763-3, 34-8579, 900G000
Page 20 of 19

Document Created: 2001-06-11 12:01:20
Document Modified: 2001-06-11 12:01:20

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