Theory of Operation
1705A Spectrum Monitor
4- 19
Q5 is a current amplifier feeding the output stage. Q3 and Q4 form a push-pull
output stage. Q3 acts as a 2.7 mA constant current pull-up, while Q4 is the
pull-down transistor. C6 speeds up the amplifier by coupling ac signals to the
base of Q3. CR2 and R41 protect the amplifier during crt arcing.
The pinout for the CRT is shown in Figure 4-3.
Pin
Description
1
Filament (f)
2
Cathode (k)
3
GRID (g1)
4
FOCUS (g3)
5
ASTIG (g4)
6
GEOM (g5)
7
VERT PLATE (y2)
9
VERT PLATE (y1)
11
HORIZ PLATE (x2)
12
1st ANODE (g2)
13
HORIZ PLATE (x1)
14
Filament (f)
14
13
12
11
9
7
6
5
4
3
2
1
Figure 4-3: Pinout of the CRT Socket
CRT
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: ......