Philips PM2521 Service Manual page 10

07
LIST
OF
FIGURES
Fig.
1.
Basic build-up of
PM2521
4
Fig. 2.
Block diagram
PIVI2521
4
Fig.
3.
Measurement
flow-chart ... 7
Fig. 4.
DC
attenuator
.1
8
Fig. 5.
AC
attenuator
8
Fig.
6.
Basic 1-V convertor 9
Fig.
7.
measurements 10
Fig.
8.
Thomson
bridge
11
Fig. 9.
Block diagram
-
frequency measurements 12
Fig. 10.
Normal
trigger
mode
13
Fig. 11.
Special
trigger
mode
13
Fig. 12.
Basic V-l convertor
14
Fig. 13.
Low-pass
active
filter
15
Fig.
14. Switching
part
ADC
15
Fig. 15.
Basic functional blocks of
8035
/mP
17
Fig. 16.
Pin allocation
and functions of 8035/xP 19
Fig. 17.
Mode
switch interrupts 21
Fig.
18.
Block diagram of the control section
24
Fig.
19.
Measuring sequence
26
Fig. 20.
Calibration routine
29
Fig.
21.
Flow-chart
internal test
and
adjust routine
28
Fig.
22.
Flow-chart
display
output routine
32
Fig. 23.
DC
attenuator details
33
Fig.
24.
AC
attenuator
details
34
Fig.
25.
I
-V convertor
35
Fig. 26.
mesusrements
details
37
Fig.
27.
Temperature
bridge
38
Fig.
28.
Frequency measurements 39
Fig. 29.
R.M.S. convertor 41
Fig. 30.
Impedance
convertor
42
Fig.
31.
Active
filter
43
Fig.
32. V-l
convertor
44
Fig.
33.
Interrupt controller
45
Fig.
34.
Counter
input control
47
Fig.
35.
Counter
48
Fig.
36.
Switch decoding
49
Fig.
37.
Relay/FET
control 51
Fig. 38.
Address decoding 54
Fig. 39.
Memory
55
Fig.
40. Display interface
56
Fig.
41
.
Removing
the
top
cover
60
Fig.
42.
Removing
the
bottom
cover
and
front
60
Fig.
43.
Removing
the front
60
Fig.
44. Front assembly 60
Fig.
45.
Removing
the thermal fuse
60
Fig.
45a.
Removing
the thermal fuse
60
Fig.
46. Adjusting elements
61
Fig.
47.
Waveforms
V~
part
74
Fig.
48.
Waveforms
trigger-level part
77
Fig.
49.
Waveform,
analog part
80
Fig. 50.
Waveform,
ADC
part 81