Page 1
8
6.2V
CB13.8V(EXT)
CB13.8V(EXT)
S5-D1
S5-D1
DIMMER
DIMMER
D D
C C
20
1
B B
1919
C231
C231
10n
10n
R207
R207
4K7
4K7
COM+
LED301LED301
Q17 Q16
Q4
T3TXT3
D8
TX
T2TXT2
TX
Q3
Q2
T1
VCOT1VCO
D3
Q1
D13
Q25
Q21
Q20
D2
IC1
LC7136
OR LC7137
*1 Q18 INCORRECTLY MARKED AS Q11 ON BOARD
RX AUDIO
PART OF FRONT PANEL CONTROLS
C213
C213
C212
C212
5n6
5n6
10n
10n
S6
VR5
VR5
HI FILTERS6HI FILTER
100K
100K
TONE
TONE
RX8.5V
Q251
Q251
2SC945
2SC945
RV5
RV5
LOW POWER
LOW POWER
T4TXT4
TX
T7
Q7
27 MHZT727 MHZ
Q8 Q9
T8
10.7 IFT810.7 IF
T9
10.7 IFT910.7 IF
Q10
T10
T10
455 IF
455 IF
Q23
Q11
2121
C88
C88
4u7
4u7
VR1
VR1
50K
50K
VOLUME
VOLUME
IC1
IC1
1
P1
2
P2
CHANNEL
3
P3
SWITCH
4
P4
5
P5
6
P6
7
TEST
8
CH19
9
CH9
10
MC
LC7137A
LC7137A
Q5
L8
L4
YELLOWL4YELLOW
Q6
T5
27 MHZT527 MHZ
IC5
NJM4558D
1
Q19
RV1
RV1
SQUELCH
SQUELCH
Q18
*1
Q22
T11
T11
455 IF
455 IF
14
Q12
1
R52
R52
2K7
2K7
R51
R51
5K6
5K6
C89
C89
47n
47n
RX8.5V
NOTES:
1. ON SOME BOARDS, C139 IS SOLDERED
ACROSS R18 (I.E. BASE OF Q4)
THIS CAUSES LOW POWER AND T3
NOT TO TUNE - MOVE IT TO T3.
2. MORE OUTPUT POWER: CHANGE Q5 TO 2SC2314.
TO S1-A MAINS
ON/OFF SWITCH
F1
2 AMPF12 AMP
TRANSFORMER
A A
TRANSFORMER
AC 230 VOLTS MAINS INPUT
D1 TO D4
T201
T201
1N5403
11
C3
F2
3 AMPF23 AMP
22nC322n
22
C1
2200uC12200u
8
R1
R1
220R
220R
1/2 W
1/2 W
ZD1
ZD1
16v2
16v2
1.2 W
1.2 W
PTPW005COX PSU
R2
R2
47R
47R
Q1
1/2 W
1/2 W
2SC900Q12SC900
R3
R3
100R
100R
1/2 W
1/2 W
2SA564
2SA564
7
L1
C6
27uHL127uH
47nC647n
R2
10KR210K
20
T/R
19
FIN
18
VCC
17
AO
16
AI
15
PD
14
LD
13
GND
12
RO
11
RI
WHITEL8WHITE
L9
GREENL9GREEN
RV2
RV2
DEVIATION
DEVIATION
RV6
ALC
IC4
TA7205
Q15
Q13
IC3
T12
T12
AN240
FM DISC
FM DISC
R53
R53
4K7
4K7
Q22
Q22
2SC945
2SC945
R65
R65
C90
C90
10K
10K
4n7
4n7
Q15
Q15
R67
R67
15K
15K
C112
C112
10n
10n
R66
R66
10K
10K
S METER
S METER
C91
C91
10n
10n
2SC945
2SC945
RV3
RV3
Q18
Q18
C1
56pC156p
RV4
RV4
RF METER
RF METER
R85
R85
10K
10K
C41uC4
C5
R3
1u
10nC510n
R1
5K6R35K6
560RR1560R
X1
C3
22pC322p
10.240 MHzX110.240 MHz
C123
C123
CT2
CT2
47p
47p
20p
20p
R911KR91
1K
R92
R92
4K7
4K7
R93
R93
2K2
2K2
Q1
Q2
Q3
Q4
Q5
Q6
Q7
Q8
Q9
Q10
Q11
Q12
Q13
Q14
Q15
Q16
Q17
Q18
Q19
Q20
Q21
Q22
Q25 0 0.7 5.5 VCO BUFFER
Q14
R54
R54
2K2
2K2
R55
R55
4K7
4K7
C92
C92
C94
C94
560p
560p
100u
100u
R58
R58
R56
R56
2k2
2k2
820K
820K
Q13
Q13
2SC1843
2SC1843
C931nC93
R57
R57
1n
C111
C111
560R
560R
10n
10n
R84
R84
15K
15K
R681KR68
1K
C106
C106
33u
33u
C107
C107
3u3
3u3
D17
D17
C124
C124
MA150
MA150
Q20
Q20
2SC710
2SC710
C125
C125
2n2
2n2
TX 1.6 2.0 8.6
TX 0 0.3 12.2 TX RF DRIVER
TX 0 0.1 12.2 TX RF OUTPUT
R69
R69
2K7
2K7
D7
1N60D71N60
R701KR70
1K
10KR410K
18p
18p
C7
47nC747n
Q21
Q21
2SC710
2SC710
C126
C126
2n2
2n2
TP1TP1
VCO TEST POINT
BASE COL
EM
4.4 4.8 8.8 VCO
0 0 8.2 TX SW
1.2 1.6 13.0 TX RF PRE-AMPTX
1.1 1.7 6.2 RF AMP
1.2
1.7
12.0
1.2
1.7
12.0
0 0.7 6.0 2ND MIXER
1.1 1.6 11.4 455KhZ IF AMP
0.5 1.1 12.5 455KhZ IF AMP
0.6 1.2 3.3 AUDIO AMP
0 0 3.2 SQUELCH CONTROL
0 0 0 ALC CONTROL
12.5 8.69.1 8.6V REGULATOR
8.8 8.0 8.6 TX 8.6V SWITCHTX
0 0.7 0 ALC INHIBIT
0 0.7 0.1 MODULATION MUTE
0 0.7 0 MIC AUDIO MUTE
C97
C97
2n2
2n2
C96
C96
10n
10n
R59
R59
82R
82R
C95*C95
*
C108
C108
3u3
3u3
C98
C98
3u3
3u3
D16
D16
MA150
MA150
PA13.8V
Q201
Q201
2SD313
2SD313
R4
R4
C6
820R
820R
22nC622n
1/2 W
1/2 W
Q2
2SC900Q22SC900
C12
C12
C2
22n
22n
100uC2100u
ZD2
ZD2
RD 5v6
RD 5v6
7
33
R5
R5
1K2
1K2
1/2 W
1/2 W
RV1
RV1
500R
500R
C4
10nC410n
R61KR6
1K
13.8 VDC OUTPUT
TO PINS 3 AND G
GG
C8
39pC839p
R4
C99
C99
220p
220p
4
4
6
6
7
7
C100
C100
33u
33u
RV6
RV6
500R
500R
ALC
ALC
R60
R60
10K
10K
PART OF FRONT PANEL
820RR7820R
2SC2724
2SC2724
1616
FUNCTION
TX FREQ DOUBLER
1ST MIXER
1ST MIXER
LOW D TUNE SW
HIGH D TUNE SW
5
5
IC4
IC4
TA7205P
TA7205P
9
9
3
3
Q14
Q14
2SC945
2SC945
C109
C109
10u
10u
GG
MIC AUDIO
6
R7
R8
150KR8150K
Q25
Q25
C19
C19
18p
18p
R11
R11
22K
22K
PART OF FRONT PANEL CONTROLS
S3
S3
DELTA TUNE
DELTA TUNE
C101
C101
68n
68n
C102
C102
47u
47u
1
1
2
2
10
10
8
8
C103
C103
220p
220p
C104
C104
R62
R62
22K
22K
R61
R61
1K8
1K8
VR2
VR2
10K
10K
SQUELCH
SQUELCH
6
5
4
3
2
1
CB13.8V
8.8V
C138
C138
47n
R13
R13
3K3
T1
T1
10DB
10DB
003
003
C26
C26
C1215pC121
82p
82p
C20
C20
D3
D13
ITT410D3ITT410
13.8V(EXT)
D13
ITT410
ITT410
C54
C54
27p
27p
D5
MA150D5MA150
D4
MA150D4MA150
FB1FB1
22p
22p
+
+
0
0
R2011KR201
-
-
1K
GND
3K3
R12
R12
47K
47K
CT1
CT1
C23
C23
20p
20p
5p
33p
33p
C21
C21
15p
15p
Q2
2SC945Q22SC945
C22
C22
10n
10n
R80
R80
39K
39K
MIDLAND 76-900-UK
1st Mixer 16.905 to 17.295 MHz
R26
R26
47K
47K
T5
T5
ETR
ETR
0333
0333
Q7
2SC2724Q72SC2724
C56
C56
47p
47p
FB2FB2
R25
R25
680R
680R
R27
R27
C55
C55
10n
10n
680R
680R
C59
C59
47n
47n
3838
GG
VR6
VR6
R202
R202
100K
100K
39K
39K
RF GAIN
RF GAIN
PART OF FRONT PANEL CONTROLS
47n
R9
220KR9220K
Q1
2SC2724Q12SC2724
C24
C24
120p
120p
330p
330p
R10
R10
C25
C25
2K7
2K7
120p
120p
PCB = PTBM134AOX
R28
R28
100R
100R
T7
T7
10CM
10CM
003M
003M
C58
C58
10n
10n
C63
C63
150p
150p
3939
MODULATION
CB13.8V
13.8V
RX8.5V
8.8V
C105
C105
220u
220u
68n
68n
R63
R63
18K
18K
RV1
RV1
20K
20K
SQUELCH
SQUELCH
PRESET
PRESET
R95
R95
270R
270R
C137
C137
33u
33u
77
R73
R73
27K
27K
R72
R72
10K
10K
C113
C113
47n
47n
RV2
RV2
C114
C114
2K
2K
6n8
6n8
DEV
DEV
S7-C
S7-C
2323
CB/PA
CB/PA
D19
D19
1N60
1N60
Q23
Q23
2SC945
2SC945
C214
C214
4n7
4n7
R96
R96
100R
100R
C215
C215
GG
4n7
4n7
R75
R75
R74
R74
10K
10K
10K
10K
C115
C115
33n
33n
C116
C116
4n7
4n7
PART OF FRONT PANEL CONTROLS
PA
PA
CB
CB
L202
L202
47u
47u
C216
C216
4u7
4u7
J6
PHONEJ6PHONE
4444
R98
R98
330R
330R
1/2 W
1/2 W
R76
R76
470K
470K
6
-
-
5
+
+
IC5B
IC5B
NJM4558D
NJM4558D
R77
R77
470K
470K
E = EXTERNAL SPEAKER
I = INTERNAL SPEAKER
E&I = EXTERNAL & INTERNAL
I
EE
E&IIE&I
SPEAKER
SPEAKER
S4-A
S4-A
SWITCH
SWITCH
44
5
7
C35
C35
10n
10n
T2
T2
T3
T3
10CB
10CB
10CA
10CA
003
003
006
C33
C33
10n
10n
T8
T8
R83
R83
4K7
4K7
C217
C217
4n7
4n7
C208
C208
4n7
4n7
C36
C36
10p
10p
10.24MhZ
C672pC67
2p
R14
R14
6K8
6K8
R82
R82
18K
18K
C120
C120
22n
22n
Q19
Q19
2SC945
2SC945
R81
R81
2K2
2K2
GG
PART OF REAR PANEL
C208
C208
4n7
4n7
5252
T9
MA06T9MA06
LL
006
CF1
CF1
10.7 MHz
10.7 MHz
THERE ARE 2
LOCATIONS FOR R81
THE NORMALLY UNUSED
ONE IS NEAR THE 10.7M
CERAMIC FILTER.
C218
C218
4n7
4n7
EXT SPJ4EXT SP
SP
SPEAKERSPSPEAKER
R15
R15
150K
150K
Q3
2SC2724Q32SC2724
C31
C31
R16
R16
390R
390R
C25
C25
10n
10n
C77
C77
R31
R31
10n
10n
470R
470R
GND
C62
C62
22p
22p
Q8
2SC2724Q82SC2724
Q9
2SC2724Q92SC2724
10MA
10MA
018M
R29
R29
2K7
2K7
R78
R78
10K
10K
S4-B
S4-B
R97
R97
4R7
4R7
1W
1W
018M
C66
C66
R30
R30
C65
C65
10n
10n
680R
680R
47n
47n
C140 IS ON
BACK OF PCB
R122
R122
5K6
5K6
C140
C140
33u
33u
GND
D14
D14
MA150
MA150
C118
C118
33n
33n
48
2
-
-
1
3
+
+
IC5A
IC5A
R79
R79
NJM4558D
NJM4558D
10K
10K
C119
C119
1n8
1n8
C207
C207
4n7
4n7
33
C139 IS ON
BACK OF BOARD
SEE NOTE 1
J3
P.A.J3P.A.
J4
R6
4K7R64K7
R17
R17
6K8
6K8
C37
C37
68p
68p
C139
C139
39p
39p
R18
R18
4K7
4K7
R361KR36
1K
R34
R34
3K3
3K3
C685pC68
5p
Q10
Q10
2SC2724
2SC2724
R33
R33
390R
390R
C69
C69
R35
R35
10n
10n
120R
120R
4
T4
T4
10CP
10CP
005M
005M
Q4
2SC2724Q42SC2724
R19
R19
68R
68R
RX SIGNAL
T10
T10
07LA
07LA
004N
004N
C70
C70
22n
22n
CAUTION AC
MAINS 230 V
TO AC MAINS SIDE
OF TRANSFORMER
PTPW005COX PSU
4
4
3
3
C210
C210
C209
C209
4n7
4n7
4n7
4n7
PART OF FRONT PANEL CONTROLS
13.8 VDC
J3
J3
MIC
MIC
TX8.6V
C39
C39
120p
120p
C38
C38
10n
10n
CF2
CF2
455 KHz
455 KHz
+
-
C206
C206
10n
10n
1
1
2
2
C40
C40
47n
47n
R43
R43
33K
33K
OFF ON
OFF ON
13.8 VDC INPUT FROM
PTPW005COX PSU
C205
C205
10n
10n
MIC GAIN
MIC GAIN
C211
C211
10n
10n
13.8V
R20
R20
330R
330R
C41
C41
390p
390p
R40
R40
680R
680R
Q11
Q11
2SC2724
2SC2724
R371KR37
1K
R38
R38
4K7
4K7
R39
R39
470R
470R
SIGNAL FOR SQUELCH CONTROL
S1-A
S1-A
ON/OFF
ON/OFF
POWER
POWER
D201
D201
1S1855
1S1855
VR3
VR3
5K
5K
CB
CB
R21
R21
220R
220R
C42
C42
10n
10n
OFF ON
OFF ON
33
GG
11
22
VR4
VR4
5K
5K
PA GAIN
PA GAIN
PA
PA
ALL CB/PA SWITCH
ARE LINK AS ONE
2424
2SC1846Q52SC1846
R119
R119
270R
270R
C72
C72
10n
10n
S7-B
S7-B
CB/PA
CB/PA
C135
C135
10n
10n
GND
C46
C46
100p
100p
R45
R45
47R
47R
T11
T11
07LA
07LA
023N
023N
C74
C74
47n
47n
C134
C134
3u3
3u3
PART OF FRONT PANEL CONTROLS
PA
PA
CB
CB
99
R86
R86
10R
10R
1/2 W
1/2 W
Q16
Q16
2SC1318
2SC1318
R87
R87
270R
270R
L12L12
D8
9.1VD89.1V
S5-D4
S5-D4
DIMMER
DIMMER
R205
R205
47R
47R
L7L7
L6L6
L9
L8
C47
C47
120p
120p
GREENL9GREEN
WHITEL8WHITE
C49
C49
390p
390p
Q6
2SC1909Q62SC1909
C48
C48
220p
220p
R38
R38
L5L5
100R
100R
C80
C80
15p
15p
D11
D11
D6
1N60
1N60
1N60D61N60
R112
R112
4K7
4K7
C75
C75
10n
10n
R46
R46
22K
22K
N/U11N/U
11
C122
C122
220u
220u
1313
TXTX PL1
ALL DIMMER SWITCH
ARE LINK AS ONE
S5-D2
S5-D2
DIMMER
DIMMER
R204
R204
27R
27R
N/U12N/U
12
R89
R89
3K3
3K3
R88
R88
390R
390R
Q17
Q17
2SA719
2SA719
R90
R90
10K
10K
MA150MA150
R47
R47
C76
C76
820R
820R
10n
10n
RV3
RV3
20K
20K
S METER
S METER
13.8V(EXT)
CB13.8V(EXT)
1414
D9
MA150D9MA150
C11
C11
47u
47u
4141
RXRX
NORMALNORMAL
ATTN
ATTN
S2-A
S2-A
PART OF FRONT PANEL CONTROLS
3232
3333
C43
C43
10n
10n
GND
L3L3
Q5
C44
C44
120p
120p
L4
YELLOWL4YELLOW
RV5
RV5
C45
C45
300R
300R
180p
180p
R42
R42
15K
15K
Q12
Q12
2SC828
2SC828
R41
R41
3K3
3K3
R44
R44
330R
330R
C73
C73
47n
47n
C71
C71
47n
47n
SW7-A
SW7-A
CB/PA
CB/PA
ALL CB/PA SWITCH
ARE LINK AS ONE
S1-B
S1-B
ON/OFF
ON/OFF
POWER
POWER
1515
CH1
CH1
CHOKE
CHOKE
L14L14
C127
C127
10n
10n
GND = TRANSMIT
CB13.8V(EXT)
3
C205
C205
C204
C204
47n
47n
100n
100n
L10L10
R23
R23
47K
47K
C512pC51
2p
D12
D12
1N60
1N60
R241KR24
C52
C52
1K
4n7
4n7
C82
C82
47u
47u
2
R50
R50
330R
330R
1
C81
C81
47n
47n
TP2TP2
RX ALIGNMENT TEST POINT
3535
2020
R5
56RR556R
D2
6.2VD26.2V
C9
47nC947n
-10dB-10dB
S2-BS2-B
2
C206
C206
C136
C136
47n
47n
47n
47n
SWR PRESET
SWR PRESET
M3
M1
PART OF REAR PANEL
SO259
SO259
ANT
ANT
22
D501
D501
1N60
1N60
C502
C502
10n
10n
RV501
RV501
10K
10K
44
GG
RV201
RV201
10K
10K
CAL PRESET
CAL PRESET
S8-B
S8-B
CAL / SWR
CAL / SWR
SWITCH
SWITCH
VR7
VR7
10K
10K
SWR CAL
SWR CAL
GG
M2
SWR METERM2SWR METER
GG
AN240
AN240
346
RX AUDIO
55
8.8V
12.5V
RX8.5V
PTSRO17AOX
11
C201
C201
150p
150p
R501
R501
100R
100R
GG
RF POWER METERM3RF POWER METER
T12
T12
07LA
07LA
023N
023N
R49
R49
47K
47K
C861nC86
C851nC85
1n
1n
6B6B
SIGNAL METERM1SIGNAL METER
L11L11
C50
C50
270p
270p
RV4
RV4
10K
10K
RF METER
RF METER
C531uC53
1u
S8-A
S8-A
CAL / SWR
CAL / SWR
SWITCH
SWITCH
5
8
C84
C84
47n
47n
14
IC3
IC3
9
10
C87
C87
22n
22n
12
7
R48
R48
C83
C83
100K
100K
22n
22n
PA13.8V
13.8V
R64
R64
47R
47R
C110
C110
1000u
1000u
GND
12.5V
C79
C79
C60
C60
47n
47n
10u
10u
CB13.8V
8.8V
RX8.5V
TX8.6V
6.2V
R100
R100
10K
10K
Q24
Q24
2SC945
2SC945
C10
C10
10n
10n
GG
PAPA
PL3
PL3
PL1
PL2
PL2
METER
METER
METER
METER
METER
METER
TX8.6V
TO PIN 14TO PIN 14
PA13.8V
MODMOD
S5-D3
S5-D3
DIMMER
DIMMER
R206
R206
27R
27R
4141
BY: Rick Jackson Euro Radio Co
BY: Rick Jackson Euro Radio Co
BY: Rick Jackson Euro Radio Co
Size Document Number Rev
Size Document Number Rev
Size Document Number Rev
MIDLAND 76-900-UK.SCH
MIDLAND 76-900-UK.SCH
MIDLAND 76-900-UK.SCH
Date: Sheet
Date: Sheet
Date: Sheet
11Wednesday, April 04, 2007
11Wednesday, April 04, 2007
11Wednesday, April 04, 2007
1
of
of
of
1.0
1.0
1.0
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