Motorola GM950 User manual

Control Heads/Control Microphones Specific Information 4-i
Chapter 4
Control Heads/Control Microphones
Specific Information
Table of Contents
Table of Contents
Chapter Page
4A Control Head for Radio Model N2 ........................................................ 4A.1-i
4B Control Head for Radio Model N3......................................................... 4B.1-i
4C Hand Held Control Microphone GMN6151...........................................4C.1-i
4D Control Head for Radio Model N4.........................................................4D.1-i

Table of Contents
4-ii Control Heads/Control Microphones Specific Information

Control Head for Radio Model N3 4B-i
Chapter 4B
Control Head for Radio Model N3
Table of Contents
Table of Contents
Chapter
4B.1 Introduction/Theory of Operation
4B.2 PCB/Schematic Diagram and Parts List

Table of Contents
4B-ii Control Head for Radio Model N3

Introduction/Theory of Operation 4B.1-i
Chapter 4B.1
Introduction/Theory of Operation
Table of Contents
Table of Contents
Paragraph Page
1.0 Introduction ................................................................................................ 1
2.0 ExplodedView Diagram ............................................................................ 1
3.0 Theory of Operation .................................................................................. 2

Table of Contents
4B.1-ii Introduction/Theory of Operation

Overview
Introduction/Theory of Operation 4B.1-1
1.0 Overview
128 Channel, Radio Model N3 Control Head
The features of the N3 radio control head are as follows:
■
■■
On/Off Button
■
■■
Rocker Type Volume Up/Down Control
■
■■
3 digit, 7 segment Backlit LCD display
■
■■
8 LCD Annunciators/Icons
■
■■
3 LEDs (Red,Yellow, Green)
■
■■
Up/Down keys for Channel Increment/Decrement
■
■■
6 Dealer Programmable Option Buttons
■
■■
Internal 4W Loudspeaker
2.0 ExplodedView Diagram
4B
.
1
Housing incl.
LCD Gasket
1502612Y01
LCD
7202695Y01 (5 Tone)
7202662Y01 (MPT /
Conventional)
Keypad
7502615Y01 (MPT)
7502615Y02 (Conventional)
7502615Y04 (5 Tone)
Printed Circuit Board
8402622Y_
Speaker
5005156Z02
and
Gasket
3205932V01
Frame LCD
0702643Y01
Connector Elastromeric
2802638Y04 top
2802638Y03 bottom
GEPD5493

Theory of Operation
4B.1-2 Introduction/Theory of Operation
3.0 Theory of Operation
3.1 General
The Control Head contains the internal speaker, the microphone connector, several buttons to
operate the radio, and several indicator Light Emitting Diodes (LED) to inform the user about the
radio status.
Additionally, the control head uses a 3 digit / 7 segment Liquid Crystal Display (LCD) for the
numerical information e.g.channel number, select code.
3.2 Power Supplies
The power supply to the Control Head is taken from the host radio’s FLT A+ voltage via connector
J0901 pin 2 and the regulated +5V via connector J0901 pin 10.The voltage FLT A+ is at battery
level and is used for the LEDs, the back light and to power up the radio via the On / Off button.The
stabilized +5 volt is used for the display, the display driver, the shiftregister and the keypad buttons.
3.3 Power On / Off
The On/Off button when pressed switches the radio’s voltage regulators on by pulling ON OFF
CONTROL to high via (D0925) and connects the base of (Q0925) to FLT A+.This transistor pulls the
line ANALOG 3 to low to inform the µ P that the On/Off button is pressed.If the radio is switched off,
the µ P will switch it on and vice versa. If the On/Off button is pressed and held while the radio is on,
the software detects a low state on line ANALOG 3 and switches the radio off.
3.4 Keypad Keys
The Control Head keypad is an (11) - key keypad. All keys are configured as 3 analogue lines
(ANALOG 1 2 3) to the radio. Lines ANALOG 1,2 each control four keys; line ANALOG 3 controls
three keys.The voltage on the analogue lines varies between 0V and +5V depending on which key
has been pressed. If a button is pressed, it will connect one of the 3 lines ANALOG 1,2,3 to a
resistive voltage divider connected to +5V.The voltages of the lines are A/D converted inside the µ P
and specify the pressed button.
3.5 Status LED and Back Light Circuit
All the indicator LEDs (4) and the back light LEDs (20) are driven by current sources (Q0942 -
Q0944, Q0951, Q0952) and controlled by the µ P via SERIAL PERIPHERAL INTERFACE (SPI).The
current is determined by the resistor at the emitter of the respective current source transistor.
Shiftregister (U0941) stores the LED status.To update the LED status line LED CLCK BUF shifts the
data of line SPI DATA BUF into the shiftregister.When all the data has been written, line LED CE is
set to low for a few microseconds to update the output of the shiftregister with the new data.

Theory of Operation
Introduction/Theory of Operation 4B.1-3
3.6 Liquid Crystal Display (LCD)
The LCD display H0931 is a 3 digit / 7 segment display which incorporates (11) annunciators. Data
is loaded serially into the display driver U0932 via the SPI interface.The display data of line SPI
DATA BUF is shifted serially into the display driver by clock signal LCD CLCK BUF.When the last bit
has been received, the LCD display is updated.
3.7 Microphone Connector
Signals BUS+, PTT, HOOKVPP, MIC HI, HANDSET AUDIO from the microphone connector (J0903)
are fed to the radio’s controller section via connector (J0901) .
3.8 Speaker
The Control Head contains a speaker for the receiver audio.The receiver audio signal from the
differential audio output of the audio amplifier located on the radio’s controller is fed via lines INT
SPKR+, INT SPKR-, connector (J0901-18,17) to the speaker connector (J0902) pin 1 and pin 2.The
speaker is connected to the connector (J0902) .
3.9 ElectrostaticTransient Protection
Electrostatic transient protection is provided for the sensitive components in the Control Head by
diodes (VR0901 - VR0909).The diodes limit any transient voltages to tolerable levels.The
associated capacitors provide Radio Frequency Interference (RFI) protection.
3.10 Reversible Control Head
The control head is connected to the RF transceiver by means of a short flexible ribbon cable.This
allows the control head to be mounted either way up in relation to the body of the transceiver.This
means that the transceiver can be mounted in the most cosmetically pleasing and most efficient
cooling orientation and still have the user interface the “right way” up.

Theory of Operation
4B.1-4 Introduction/Theory of Operation

PCB/Schematic Diagram and Parts List 4B.2-i
Chapter 4B.2
PCB/Schematic Diagram and Parts List
Table of Contents
Table of Contents
Description Page
Control Head (N3) - Diagrams and Parts Lists
PCB Layout Component Side . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
PCB Layout Solder Side . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
Schematic Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
Parts List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Table of Contents
4B.2-ii PCB/Schematic Diagram and Parts List

Control Head (N3) PCB No. 8402622Y04_T2
Diagrams and Parts List 4B.2-1
Control Head (N3)
PCB No. 8402622Y04_T2
C0901
C0902
C0903
C0904
C0905
C0906
C0911
C0915
C0925
C0926
C0934 C0935
C0941
C0942
D0925
J0901
J0902 Q0925
Q0941 Q0942
Q0943
Q0944
Q0951
Q0952
R0901
R0911
R0912
R0913
R0914
R0915
R0916
R0917
R0918
R0919
R0920
R0921
R0922
R0925
R0926
R0933
R0941 R0942 R0943
R0944
R0945
R0946
R0947
R0948
R0951 R0952
R0953 R0954
U0932
U0941
VR0901
VR0902
VR0903
VR0904
VR0905
VR0906
VR0907
VR0908
VR0909
Solder Side 8402622Y04 GEPD5399
-
2
Bottom Side
D0941
D0942
D0943
D0944
D0951
D0952
D0953
D0954
D0955
D0956
D0957
D0958
D0959
D0960
D0961
D0962
D0963
D0964 D0965
D0966
D0967
D0968 D0969
D0970
H0931
J0903
R0902
Top Side

Control Head (N3) PCB No. 8402622Y04_T2
4B.2-2 Diagrams and Parts List

Control Head (N3) Schematic Diagram
Diagrams and Parts List 4B.2-3
Control Head (N3) Schematic Diagram
2
4
6
1
3
5
2
4
6
1
3
5
2
4
6
1
3
5
2
4
6
1
3
5
2
4
6
1
3
5
2
4
6
1
3
5
2
4
6
1
3
5
2
4
6
1
3
5
2
4
6
1
3
5
11 2 23
3
BPO
BP I B1
B2 B3 B4 B5 B6
B7
B8 B9
B10 B11 B12
B13 B14
B15
B16
B17 B18
B19
B29
B20 B21 B22 B23 B24 B25 B26 B27 B28 B30 B31 B32 B33

Control Head (N3) Schematic Diagram
4B.2-4 Diagrams and Parts List
Control Head (N3)
Parts List
Circuit
Ref Motorola Part No. Description
C0901 2113741F17 470pF 50V
C0902 2113741F17 470pF 50V
C0934 2113743K15 100nF 16V
C0935 2113741F49 10nF 50V
C0941 2113743K15 100nF 16V
C0942 2311049J23 TANT CP 10uF 10% 6V
D0925 4813833C02 DUAL SOT MMBD6100
D0941 4805729G73 LED SMTYEL
D0942 4805729G73 LED SMTYEL
D0943 4805729G74 LED SMT RED
D0944 4805729G75 LED SMT GREEN
D0951-
D0970 4805729G75 LED SMT GREEN
H0931 7202631Y01 CNTL K DISPLAY
J0901 0902636Y01 CONN FLEX Side Entry
J0902 2809926G01 CONN 1.25MM CTR SUR
J0903 2805924V01 CONNECTOR MIC
Q0925 4880048M01 NPN DIG 47k/47k
Q0931 4805128M16 PNP SOT MMBT3906
Q0941 4880048M01 NPN DIG 47k/47k
Q0942 4813824A10 NPN 40V .2A B=50-150
Q0943 4813824A10 NPN 40V .2A B=50-150
Q0944 4813824A10 NPN 40V .2A B=50-150
Q0951 4813824A10 NPN 40V .2A B=50-150
Q0952 4813822A20
R0901 0660076A35 270 5 1/8
R0902 0662057A49 1k 1/16W 5%
R0911-
R0922 0662057A65 4k7 1/16W 5%
R0925 0662057A65 4k7 1/16W 5%
R0926 0662057A65 4k7 1/16W 5%
R0931 0662057A65 4k7 1/16W 5%
R0932 0662057A73 10k 1/16W 5%
R0933 0662057A97 100k 1/16W
R0941 0662057A73 10k 1/16W 5%
R0942 0662057A89 47k 1/16W 5%
R0943 0662057A89 47k 1/16W 5%
R0944 0660076A35 270 5 1/8
R0945 0662057A89 47k 1/16W 5%
R0946 0662057A41 470 1/16W 5%
R0947 0662057A89 47k 1/16W 5%
R0948 0660076A35 270 5 1/8
R0952 0662057A80 20k 1/16W 5%
R0953 0662057A73 10k 1/16W 5%
R0954 0680194M01 10 1W 5%
U0932 5105625U61 LCD DRIVER
33 SEGMENT STATIC
U0941 5113806A35 MC14094, REG,
8-STAGE,SHIFT/STOREU
VR0901 4813830A14 5.1V 5% 225mW
VR0902 4813830A14 5.1V 5% 225mW
VR0903 4813830A27 14V 5% 225mW
VR0904 4813830A27 14V 5% 225mW
VR0905 4813830A27 14V 5% 225mW
VR0906 4813830A14 5.1V 5% 225mW
VR0907 4813830A14 5.1V 5% 225mW
VR0908 4813830A14 5.1V 5% 225mW
Circuit
Ref Motorola Part No. Description