Hameg HM 303-4 User manual

®
Instruments
Oscilloscope
HM 303-4
ENGLISH 4S-0303-04E0 10 JUN 1998
SERVICE-MANUAL HM303-4

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Y-Preamplifier CH I (YP-Board).................................. 4
Y-Preamplifier CH II (YP-Board)................................. 5
Y-Intermediate Amplifier and Trigger Amplifier
(YP-Board) ................................................................. 6
YPA-Board (Top side)................................................. 7
YPA-Board (Bottom side) .......................................... 8
XY-Amplifier, YF-Amplifier, OS-Circuit ....................... 9
XY-Board (Top side) ................................................. 10
XY-Board (Bottom side)........................................... 11
Sync.-Amplifier........................................................ 12
Time base................................................................ 13
Sweep-Generator .................................................... 14
TB-Board ................................................................. 15
CRT-Board ............................................................... 16
CRT-Board (Top and Bottom side) ........................... 17
Power Supply (PS-Board)........................................ 18
PS-Board (Top side)................................................. 19
PS-Board (Bottom side) .......................................... 20
Component tester, Calibrator .................................. 21
CCT-Board (Top and Bottom side) ........................... 22
Front-Control Board................................................. 23
Front-Control Board (Top and Bottom side) ............ 24
ADJUSTMENT PROCEDURE ................................. 25
Table of contents
Service Manual
Circuit Diagrams
Adjustment Procedure
HM303-4
St. 100698. Hüb/goRR

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30MHz Standard Oscilloscope HM303
Accessories supplied: Line cord, Operators Manual, 2 Probes 1:1/10:1
Specifications
Vertical Deflection
Operating modes: Channel I or II separate,
bothChannels(alternatedorchopped),
(Chopperfrequencyapprox.0.5MHz).
Sum ordifference with Ch. I and Ch. II
(bothchannelsinvertable).
XY-Mode: via channel I and channel II
Frequency range: 2xDCto 30MHz(−3dB)
Risetime:<12ns.
Overshoot≤1%.
Deflection coefficients: 12 calibrated steps
from5mV/div.to20V/div.(1-2-5 sequence)
with variable 2.5:1 up to50V/div.
Accuracy in calibrated position: ±3%
Y-expansion x5 (calibrated)to1mV/div. (±5%)
in the frequency range from DC - 10MHz (–3dB)
Input impedance: 1MΩII20pF.
Inputcoupling:DC-AC-GD(ground).
Input voltage: max. 400V (DC + peak AC).
Triggering
Automatic:(peak topeak) <20Hz-100MHz(≤0.5div.)
Normal with level control:DC-100MHz (≤0.5div.)
ALT. Triggering; LED indicator for trigger action
Slope:positiveornegative,
Sources: Channel I or II, CH. I alternating CH II,
line,external
Coupling: AC (10Hz to 100MHz),
DC(0 to 100MHz),
LF (0 to 1.5kHz)
ActiveTV-Sync-Separator (pos. and neg.)
External: ≥0.3p-p from 30Hz to 30MHz
Horizontal Deflection
Time coefficients:20 calibrated steps
from0.2s/div. - 0.1µs/div.in 1-2-5 sequence
Accuracy in calibrated position: ±3%.
Min. speed incl. variable 2.5:1 up to 0.5s/div.
with X-Mag. x10: ±5%; 10ns/div.: ±8%
Holdoff time: variable to approx. 10:1
BandwidthX-amplifier:0-3MHz(−3dB).
InputX-Amplifier viaChannel II,
(sensitivity see Channel II specification)
X-Y phase shift: <3° below 220kHz.
Component Tester
Test voltage: approx. 6Vrms(open circuit).
Test current: approx. 5mArms (shorted).
Test frequency: approx. 50Hz
Test connection: 2 banana jacks 4mm∅
One test lead is grounded (Safety Earth)
General Information
CRT:D14-364GY/123orER151-GH/-,
6" rectangular screen (8x10cm)
internalgraticule
Accelerationvoltage: approx2000V
Trace rotation: adjustable on front panel
Calibrator: square-wave generator (tr<4ns)
≈1kHz / 1MHz; Output: 0.2V ±1% and 2V
Linevoltage:100-240VAC±10%,50/60Hz
Power consumption: approx. 36 Watt at 50Hz.
Min./Max.ambienttemperature:0°C...+40°C
Protective system: Safety class I (IEC 1010-1)
Weight:approx.5.6kg,color:techno-brown
Cabinet: W 285,H125,D380 mm
Lockabletilthandle
5/96
Screen photo of 1 MHz square wave signal
Screen photo of 50 and 100MHz
sinewavewithalternatetriggering
The new HAMEG HM303 oscilloscope succeeds the HM203 (over 170,000
soldworldwide).Thebandwidthhasbeenextendedfrom20to30MHz,thesweep
rate increased to 10ns/div. and improvements added to the already legendary
HAMEGauto triggering system. TheHM303is the ideal instrument for waveform
display in the DC to 100MHz frequency range.
Akeyfeatureofthisoscilloscopeistheverticalamplifier'spulsefidelity,limiting
overshoot to only 1%. The HM303 offers a special fast rise time 1kHz/1MHz
Calibrator, permittinghighqualityprobecompensationacrosstheentirefrequency
range to ensure probe-tip thru to display integrity. An Overscan Indicator assists
in vertical display amplitude and position adjustment.
The HM303 is capable of triggering on input waveforms over 100MHz and on
signal levels as small as 0.5 division. Alternate triggering mode enables the
display of two asynchronous signals simultaneously. An active Video Sync-
Separator permits detailed examination of complex TV signal inputs. A well
proven, built-in component tester is now equipped with a stabilized measuring
voltage. The use of a switching type of power supply minimizes both weight and
power consumption and universally accepts a wide range of input power line
voltages, without the requirement to change jumpers or switch positions. The
HM303's CRT is fully mu-metal shielded against outside magnetic fields.
HAMEGissettingnewprice/performancebreakthroughswiththeintroduction
ofthis fine oscilloscope.This performancepacked scope willtempt allusers to run
it through its paces.
OSCILLOSCOPES
Dual Channel, DC to 30MHz, 1mV/div.; Overscan Indicator
Time Base: 0.2s to 10ns/div.; Variable Holdoff; Alternate Triggering
Triggering: DC-100MHz; Auto Peak to Peak; Active TV-Sync-Separator
Additional Features: Component Tester, 1kHz/1MHz Calibrator

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Y-Preamplifier CH I (YP-Board)

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5
Y-Preamplifier CH II (YP-Board)

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6
Y-Intermediate Amplifier and Trigger Amplifier (YP-Board)

Subject to change without notice
7
YPA-Board (Top side)

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YPA-Board (Top side)

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9
XY- Amplifier, YF- Amplifier, OS- Circuit

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10
XY Board (Top side)

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XY Board (Top side)

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12
Sync.- Amplifier

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13
Time base

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14
Sweep- Generator

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TB Board

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CRT- Board

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CRT Board (Top and Bottom side)

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Power Supply (PS-Board)
A B C D
87654321
D C B A
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Title : Rev.:
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Date :
Document Number :
MPT
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DR1001
ETD39/303
P1001 Power Recept.
S1001
NT
R1001
NTC 8
C1006
2200p
Y 250V
U
R1005
S14K275
C1003
0.33u
X2 250V
14
32
L1001
2x33mH 1A
C1002
0.1u
X2 250V
R1019
1K00
R1030
681R
R1020
75K
D1007
BZV55B16
C1001
4700p
Y 250V
+
C1011
68u 400V
+
C1025
68u 400V
F1001
0.5AF
R1037 8K25
R1031 200K
1
2
4
6
5
IC1001
CNY17-2Z
R1068
1K3
R1065 1K3
C1027
220p 400V
R1018 100K
411
R1060
4K99
6
3
2
8 5 1
4
7
IC1003
C1041 0.1u 50V
+
C1020
220u 16V
R1045
10K0
C1012 1n 250V
R1039
200R
R1032
5K11
R1026
47K5 R1033
1K82
R1008
1K0
23
D1011
BAS20
D1017
BYD37M
R1017 100K 411
1
32
T1003
STHV82FI ISOWATT 218
R1013
R207
200K
R1021
75K
C1005
2200p
Y 250V
3
21
IC1002
TL431C
TO-92A
C1021
100p 2kV
D1022
BYD77G
D1019
BYD77G
R1010
R207 90R9
D1027
BYD37M
+
C1026
330u 25V
+
C1029
1000u 16V
+
C1023
1000u 16V
+
C1022
330u 25V
C1033 0.1u 400V MKT
L1005
68uH 1.5A
L1004
68uH 1.5A
L1003
220uH 1A
C1035
10n 400V
MKT
D1025
DD1400
D1024
DD1400
D1016
DD1400
1
2 3
4 5
6
P1010
WIRE6
+
C1009
100u 35V
D1014
BYD37M
D1012
BYT01-400
+
C1015
100u 16V
R1035
22R
R1015 0R22
2W
2
3
1
T1011
BC850c
SOT-23
1
2
3
T1009
BC860
SOT-23
c
C1044
1n 50V
R1059
1K00
R1047 22K1
4
2
1
3
D1001
FL406
+
C1030
10u 250V
+
C1017
1u 50V
+
C1028
22u 160V
D1026
BYD37M
3
2
1
T1004
TO-126
BD434
2
3
1
T1012
BC850
SOT-23
c
R1062
619R
+
C1032
100u 16V
R1053
619R
1
2
3
T1008
BC860
SOT-23
c
3
21
T1002
BD433
TO-126 C1042
1n 50V
R1061 10K0 R1056 10K0
+
C1034
100u 16V
R1054 3K01
- +3
2
1
IC1004A
TL082CN
R1055
511R
R1043
7K50
C1045
0.1u 50V
C1046
0.1u 50V
2
31
T1006
BF822
R1024
1M00
R1011 10M0 VR37
R1034
1M00
R1027
0R0
R1023
750K
C1004 47n 2kV
D1010
BZV55C75
R1067 1K00
R1057
4K32
2
3
1
T1007
BF822
SOT-23
R1012 6M81
VR37
R1064
47K5
R1044
475K
R1041
475K
R1040 10K0
R1006 470K
R1007 1M00
1
2
3
T1005
BC860
SOT-23
c
C1018
10n 400V
C1024
68p 3KV
C1007 10n 400V
C1010
0.1u 100V
R1004
470K
R1003
470K
C1043
10n 50V
R1069 8K25
1 2 3 4 5 6
P1003
WIRE6
R1028
1M00
D1005
LL4151
D1018 LL4151
R1058
750K
R1046 22K1
1
2 3
4 5
6
P1005
WIRE6
B1003
1
2 3
4 5
6
P1002
MOLEX6S
R1002
332K VR37
+Vcc -Vcc
4
8
IC1004C
TL082CN
C1019 10n 2kV
R1025 27k4
R1014
0R39
2
31
T1010
BC850
SOT-23
c
R1052 511R
R1051
12K1
D1015
LL4151
- +5
6
7
IC1004B
TL082CN
R1063 2k21
3
21
IC1005
TL431C
TO-92A
R1071
1K0
R1072 3K32
R1016
1K0
R1070
1K00
D1023
LL4151
R1066
7K50
R1029
1M00
R1009
R207
90R9
B1007
D1013
LL4151
D1020
BYD37M
D1021
BYD37M
1
2 3
4 5
6
P1008
WIRE6
B1008
B1009
B1011
1
2 3
4 5
6
P1009 WIRE6
L1006
68uH 1.5A
C1016
0.1u 100V
1
2 3
5 4
6 7 8 9 10
B1010
D1009
BYD37M
D1004
BYV27-100
D1003
BYV27-100
R1022
1K82
R1036
750K
R1042
750K
B1013
+
C1031
22u 160V
L1007
68uH 1.5A
+
C1036
10u 250V
C1037
0.1u 250V
MKT
13 14 15 16 17 18 19 20 21
C1040 0.1u 50V
R1038
0R0
C1039
4n7 50V
D1006 LL4151
R1050
332K
R1048
301K
R1049
56K2
1
3
2
T1001
BUX86
TO-126
B1001
R1073
R207
1K0
R1074
75K
+
C1038 1u 50V
LINE
+185V
+141V
31V
+12V
-12V
+12V
G1
LINE
+12V -12V
G1
-13.5V
+13.5V
12.9V
0.4V
+13.5V
-13.5V
HVC
+12V
-12V
+141V
+185V
-12V +12V
6.3V
FOKUS
HT14
-1950V
-1950V
+12V
BLV
BLV
HT1
HT14
-2025V
HT1

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PS-Board (Top side)