FILTER
RESOLUTION
FILTER
VIDEO
+5V
2
1
DS144A
DS144
RESOLUTION
+5V
2
1
DS129A
DS129
VIDEO
+5V
2
1
DS112A
DS112
FILTER
ON
LED_ON
+5V
FILTER
300 KHz
FILTER
RESOLUTION
10 KHz
INPUT
L BAND
INPUT
70 MHz
LED_300K
LED_10K
+5V
+5V
DS130
6
5
DS129C
LED_LBAND
LED_70M
+5V
+5V
DS145
6
5
DS144C
INPUT
SPAN/DIV
+5V
S109
S139
SPAN/DIV
FILTER
BANDWIDTH
INPUT
S123
NC
FILTER
INPUT
SPAN_UP
SPAN_DN
LED_LBAND
LED_FULL
LED_10M
LED_1M
LED_100K
BANDWIDTH
1A
1
1B
2
2A
3
2B
4
3A
5
3B
6
4A
7
4B
8
5A
9
5B
10
6A
11
6B
12
7A
13
7B
14
8A
15
8B
16
9A
17
9B
18
10A
19
10B
20
11A
21
11B
22
12A
23
12B
24
13A
25
13B
26
14A
27
14B
28
15A
29
15B
30
16A
31
16B
32
17A
33
17B
34
J303
CONNECTS
BOARD
J303
<5>
A3
MAIN
TO J1
A2
NC
ROTATE
CFT
INTENS
FOCUS
SCALE
LED_ON
LED_300K
LED_10K
LED_70M
S_SPD
H_POSN
SPAN_UP
SPAN_DN
S345
R211
20K
LED_FULL
S311
DS337
SPAN/DIV
FULL
R444
20K
LED_10M
R343
35.7K
DS330
1
0
9
DS319E
1
4
1
3
DS319G
SPAN/DIV
1 MHz
SPAN/DIV
10 MHz
LED_1M
DS325
6
5
DS319C
NOTE: OLD LED PART REFERENCE
NUMBERS SILKSCREENED ON BOARD,
AND IN PARTS LIST.
SPAN/DIV
100 KHz
LED_100K
2
1
DS319A
DS319
NOT INSTALLED
4
3
DS112B
6
5
DS112C
4
3
DS129B
4
3
DS319B
8
7
DS319D
4
3
DS144B
1
2
1
1
DS319F
INTENS
POSITION
VERTICAL
R528
20K
INTENS
V_POSN
+11.8V
+11.8V
--- 11.8V
--- 11.8V
SCALE
SWEEP
SPEED
R428
20K
SCALE
S_SPD
+11.8V
+11.8V
--- 11.8V
FOCUS
R411
20K
FOCUS
+11.8V
+11.8V
--- 11.8V
NC
NC
V_POSN
--- 11.8V
+11.8V
+5V
A2 FRONT PANEL BOARD
GND
FROM J23
<4>
10 TURN
CENTER
FREQUENCY
R235
20K
CFT
TRACE
ROTATION
R419
20K
ROTATE
--- 11.8V
HORIZONTAL
POSITION
R511
20K
H_POSN
--- 11.8V
+15V
C581
.1UF
R581
1.50K
C580
100UF
B C E
Q596
CR481
Q481
R485
475.0
CR485
C491
1UF
R494
71.5
CR494
Q596
+40V
R585
475.0
CR594
R690
1
2W
Q588
R687
3.01K
C690
100UF
R688
1.00K
R691
3.01K
L591
250UH
C497
10UF
R692
3.01K
R693
3.01K
1
1
2
2
3
3
4
4
5
5
J698
+40V
+15V
DS698
L695
100UH
R696
1K
1/2W
C697
10UF
NC
ON
OFF
+40V
+15V
1
1
2
2
3
3
4
4
5
5
W698
FROM J21
FROM J22
A3
MAIN
BOARD
REAR
PANEL
REAR
PANEL
LNB POWER
NC
<1>
E5
S100
+18V
LNB POWER
R588
1.00K
R587
1.00K
Q482
R686
56.2K
+3.75V
C583
2200PF
VCC
1
VZ
2
FB
3
GAIN
4
GND
8
OUT
7
SEN
6
RC
5
U583
NE5561N
C683
.01UF
R685
15.0K
R586
10.0K
R682
267.0K
+8.2V
R681
10.0K
Q783
C684
.01UF
R680
7.50K
C782
10UF
C682
.1UF
1705A SPECTRUM MONITOR
FRONT PANEL & 18V SUPPLY <6>
A4 18V POWER SUPPLY BOARD
Summary of Contents for 1705A
Page 13: ...Service Safety Summary xii 1705A Spectrum Monitor ...
Page 17: ...Preface xvi 1705A Spectrum Monitor ...
Page 18: ...Introduction ...
Page 19: ......
Page 38: ...Operating Instructions ...
Page 39: ......
Page 61: ......
Page 62: ...Installation ...
Page 63: ......
Page 72: ...Theory of Operation ...
Page 73: ......
Page 93: ...Theory of Operation 4 20 1705A Spectrum Monitor ...
Page 94: ...Checks and Adjustments ...
Page 95: ......
Page 123: ...Checks and Adjustments 5 28 1705A Spectrum Monitor ...
Page 124: ...Maintenance ...
Page 154: ...Options ...
Page 155: ......
Page 158: ...Replaceable Electrical Parts ...
Page 159: ......
Page 189: ...Replaceable Electrical Parts 8 30 1705A Spectrum Monitor ...
Page 190: ...Diagrams Circuit Board Illustrations ...
Page 191: ......
Page 193: ......
Page 213: ......
Page 214: ...Replaceable Mechanical Parts ...
Page 215: ......
Page 223: ......