Philips PM 3214 User manual

PHILIPS
25
MHz
Dual
Channel Oscilloscope
9499 440 16602
~M
3214
(9444 032 14..1)
761231/1/01/02

- PHILIPS
PHILIPS
Instruction
manual
Anleitung
Notice
d'emploi
et
d'entretien
25
MHz Dual
channel
oscilloscope
25 M
Hz Zweikanal -
Oszillograf
Oscilloscope 25
MHz
a double
trace
PM
3214
(9444 032 14. .1 ~
9499 440 16602
761231/1/01/02

1
2
Contents
1 GENERAL
INFORMATION
9
1.1 INTRODUCTION
9
1.2 TECHNICAL DATA
10
1.2.1 C.R.T.
10
1.2.2 Vertical or Y-axis
10
1.2.3
Horizontal or X-axis
11
1.2.4 Main time base
11
1.2.5 Delayed time
base
11
1.2.6
X Deflection
12
1.2.7 Triggering
of
the
main time base
12
1.2.8
Triggering of the delayed
time base
12
1.2.9 Calibration
generator
12
1.2.10
Power supply
13
1.2.11 Environmental conditions
13
1.2.12 Mechanical data
13
1.3 ACCESSORIES
13
1.3.1 Supplied
with the instrument
13
1.3.2 Optional
14
2 DIRECTIONS
FOR USE
15
2.1 INSTALLATION 15
2.1.1 Safety regulations
15
2.1.2
Local
mains
connection and
fuse protection 15
2.1.3 Connection
to an external
supply
16
2.1.4 Front cover and
instrument
positions
16
2.2 CONTROLS AND SOCKETS
16
2.2.1
Cathode-ray
tube and
POWER controls
16
2.2.2 Vertical channels
17
2.2.3
Horizontal channel
17
2.2.4
Main time base
generator
18
2.2.5
Delayed time
base generator
19
2.2.6 Miscellaneous
19
2.3 OPERATING INSTRUCTIONS 21
2.3.1 Switching on the
instrument
21
2.3.2 Preliminary settings of the controls
21
2.3.3 Input coupling (AC/DC,
0)
21
2.3.4 Use
of
probes
21
2.3.5 Selection
of
chopped or alternate
modes
21
2.3.6 Differential mode 22
2.3.7
Selection
of trigger mode 22
2.3.8 Triggering source 23
2.3.9 X
Y
measurements
24
2.3.10 Using the delayed time base
24
© N.V. PHILIPS'
GLOEILAMPENFABRIEKEN -
EINDHOVEN -THE
NETHERLANDS - 1976.
PRINTED IN THE
NETHERLANDS
i
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3
—• 3
SERVICE
DATA
59
-.
3.1 BLOCK
DIAGRAM
DESCRIPTION
59
3.1.1
Y Channel
59
3.1.2
Main time -base triggering
59
3.1.3
Main time -base
circuit
3.1.4
Hold
-off
circuit
59
3.1.5
Z-axis
59
3.1.6
Delayed time
-base triggering
60
3.1.7 Delayed
time -base circuit
60
~
3.1.8 Alternate
time -base
logic 60
3.1.9
Power supply 60
~.
3.2
DISMANTLING
61
3.3 PARTS LISTS
AND
DIAGRAMS
71
FIGURES
1.1. 25
MHz
dual
-channel
oscilloscope
PM 3214
9
2.1.
Rear view
of
the oscilloscope showing
the voltage adapter set to
220 V
15
2.2.
Front view of the oscilloscope showing controls and sockets
16
2.3.
How to compensate
passive 10:1 probes and the effect on waveforms.
20
2.4.
Suppression of common mode
signals
22
2.5. Block diagram
of
composite
trigger circuit
23
3.1. Block
diagram of the
oscilloscope
58
—`
3.2. Removing the instrument covers and the carrying handle
62
3.3. Pivot centre
button
62
3.4.
Removing the delay
-time
multipl ier knob
64
3.5.
Removing
the front
assembly
(screws C)
64
3.6.
Removing the
push-button
switches (screws
D)
65
-~ 3.7.
Removing
the
front assembly
(screws
E)
65
3.8.
Removing the front
assembly
(screws
F)
66
3.9. Push-button set
clamping device
66
3.10.
Replacing apush-button switch
66
3.11. Replacing the
thermal fuse 67
_„ 3.12. Front view
showing item numbers 70
3.13.
Rear view
showing
item numbers 70
3.14. Vertical
attenuator
unit gg
3.15. Power supply unit g0
3.16.
Vertical
amplifier unit g2
_, 3.17. Circuit
diagram
of
the complete
oscilloscope PM 3214. 93

4
I
nhaltsverzeichnis
1 ALLGEMEINES
25
1.1 EINLEITUNG
25
1.2
TECHNISCHE DATEN
26
1.2.1
Elektronenstrahlrohre
26
1.2.2
Vertikale
oder Y-Achse
26
1.2.3
Horizontale oder X-Achse
27
1.2.4
Hauptzeitablenkung
27
1.2.5
Verzogerte
zeitablenkung
27
1.2.6 X-Ablenkung 28
1 .2.7
Triggerung der
Hauptzeitablenkung
28
1.2.8 Triggerung der
verzogertenzeitablenkung
28
1.2.9
Kalibriergenerator
28
1.2.10
Stromversorgung
29
1.2.11
Umgebungsbedingungen
29
1.2.12
Mechanische Daten
29
1.3
ZUBEHOR
30
1.3.1
Standardzubehor
30
1.3.2 Wahlzubehor
30
2. GEBRAUCHSANLEITUNG
31
2.1
INBETRIEBNAHME
31
2.1.1
Sicherheitsvorschriften
31
2.1.2
Ortlicher Netzanschluss and Sicherung
31
2.1.3 Anschluss an eine
externe Stromversorgung
32
2.1.4 Abdeckhaube
and Betriebslage
32
2.2
BEDIENUNGSELEMENTE
UND
BUCHSEN
32
2.2.1 Elektronenstrahlrohre and
POWER-Einstel
lelemente
32
2.2.2
Vertikale Kanale
33
2.2.3
Horizontaler
Kanal
33
2.2.4
Hauptzeitablenkgenerator
34
2.2.5 Verzogerter
zeitablenkgenerator
34
2.2.6 Verschiedenes
35
2.3 BEDIENUNGSANLEITUNG
36
2.3.1
Einschalten des
Gerats
36
2.3.2
Vorbereitende
Einstellungen
36
2.3.3 Eingangskopplung
36
2.3.4 Anwendung von Messkopfen
36
2.3.5
Einstellen
der geschoppten oder der alternierenden
Darstellungsart
36
2.3.6 Differentielle Betriebsart
38
2.3.7
Einstellen
der
Triggerungsart 38
2.3.8
Triggerquelle 39
2.3.9 X
-Y
Messungen
40
2.3.10 Gebrauch
der verzogerten
zeitablenkung 40
Y

5
,_
BILDVERZEIGNIS
1.1. 25
MHz
Zweikanal-Oszillograf
25
2.1 .
Ruckansicht des
Oszil
lografen mit
Spannungs
umschalter
in
220 V Stellung
31
2.2.
Vorderansicht des Oszillografen
mit
Bedienungsorganen
and
Buchsen
32
2.3. Die Kompensation von passiven
10:1 Messkopfen and der Einfluss
auf Signalformen
37
2.4.
Gleichtaktunterdrtackung
38
2.5. Blockschaltbild der zusammengesetzte (composite) Triggerschaltung
39

1
6
Table des
matieres
1. GENERALITES
41
1.1. INTRODUCTION
41
1.2 CARACTERISTIQUES
42
1.2.1 Tube cathodique
42
1.2.2 Axe
vertical ou
Y
42
1.2.3
Axe X ou horizontal
43
1.2.4 Base de temps
principale
43
1.2.5
Base de temps retardee
43
1.2.6 Deviation X
44
1.2.7 Declenchement de
la
base de temps principale
44
1.2.8
Declenchement de la
base de temps retardee
44
1.2.9
Generateur d'etalonnage
45
1.2.10
Al
imentation
45
1.2.11 Conditions ambiantes
45
1.2.12 Caracteristiques
mecaniques
45
1.3.
ACCESSOIRES
46
1.3.1
Fournis
avec
('instrument
46
1.3.2 En option
46
2. MODE D'EMPLOI
47
2.1
INSTALLATION
47
2.1.1
Reglements
de
securite
47
2.1.2 Branchement sur le secteur
et fusibles
47
2.1.3
Branchement
sur
une alimentation exterieure
48
2.1.4 Couvercle avant
et position
de
('instrument
48
2.2
COMMANDES
ET
PRISES
48
2.2.1 Tube cathodique et
commander de puissance
48
2.2.2 Deviation verticale
49
2.2.3
Deviation horizontale
49
2.2.4
Generateur de base de
temps principale
50
2.2.5 Generateur de base de
temps retardee
51
2.2.6 Divers
51
2.3
INSTRUCTIONS
D'UTILISATION
52
2.3.1
Mise de
('instrument en circuit
52
2.3.2
Reglage
preliminaire des commander
52
2.3.3
2.3.4
Couplage
d'entree
Emploi des sondes
52
52
r
2.3.5 Choix entre modes commute
et alterne
52
2.3.6
Mode
differentiel 5q
2.3.7
Choix
du
mode de
declenchement 54
2.3.8 Source de
declenchement
55
2.3.9
Mesures
XY
56
2.3.10 Utilisation de la base
de temps
retardee
56
i

7
FIGURES
1.1. Oscilloscope 25 MHz
a double
trace
PM 3214
41
.,,
2.1. Vue arriere de
('oscilloscope avec carrousel
en position 220
V
47
2.2. Vue avant
de
('oscil loscope montrant
les commander et douilles
48
2.3.
Comment compenser les sondes passives 10:1 et
I'effet
sur
les
formes d'ondes
53
'" 2.4. Rejection en
mode commun
54
2.5.
Schema synoptique
du
circuit de declenchement mixte
55

Operating
manual

9
-- 1. General information
1.1
INTRODUCTION
.~
..,
....
The 25
MHz
dual
-channel
oscilloscope
PM 3214 is
a compact,
portable instrument, ergonomically designed to
facilitate its extensive measuring capabilities.
The instrument provides
both
a main and
a delayed timebase
with provision
for alternate timebase
displays,
comprehensive
triggering
facilities
including
peak
-to -peak Auto,
DC
coupling
and automatic TV waveform
display.
A large 8 x 10 cm screen
with
illuminated
internal
graticule
lines makes for easier viewing, and a 10
kV
accelerating
potential
gives a high intensity
trace with awell-defined spot.
A double -insulated
power
supply allows
the frame
ground to
be directly connected to floating ground circuits
provided
that this
ground
does not carry
live
potentials.
By this means, interference
by ground
currents, as is
frequently
experienced with grounded oscilloscopes, is also
substantially reduced.
The
wide
range
of
applications enabled by
the
above features
is further extended by a versatile power
supply
that enables the instrument to be operated
from
any line
voltage or
frequency as
well as from d.c. For field
operation an
optional
battery version
is
also available.
Warning: The frame ground land the
ground
lead
of
the
probe) must
not
be connected to live potentials.
Fig. 1.1. 25 MHz
dual -channel oscilloscope
PM
3214

10
1.2
TECHNICAL DATA
Properties
expressed in
numerical values
with
stated
tolerances are
guaranteed
for ambient
temperatures
of
+5
° C ....
+
40 ° C
unless stated
otherwise.
Numerical
values
without tolerances
are
typical and represent
the
characteristics
of
an
average instrument.
1.2.1
Designation
C.R.T.
Type
Measuring area
Screen
type
Total
acceleration
Graticule
Engravings
1.2.2 Vertical or Y-axis
Display modes
Channel B
polarity
Response:
Frequency range
Rise time
Pulse aberrations
Deflection coefficients
Continuous
control
range
Deflection accuracy
Input impedance
input
RC time
Maximum permissible input
voltage
Chopping frequency
Vertical positioning range
Dynamic range
Visible signal delay
C.M.R.R.
in A -B mode
Cross talk between
channels
Instability of the spot
position:
Temperature drift
Specification
D14-125
GH/08
8
x 10 divisions
P31
(GH)
10
kV
Internal
Centimetre divisions
with
subdivisions
of
2 mm
along
the central
axis.
Dotted
lines indicate 10%
and
90%
of measuring
lattice for
measurement
of
rise
time.
Channel A only
Channel B only
A and
B chopped
A and B
alternated
A and B added
Normal or
inverted
DC :
0 ....
25
MHz
(-3 dB)
AC : 2
Hz
....
25 MHz
(-3
dB)
14
ns
2
mV/DIV
.... 10
V/DIV
1 :
~
2,5
±3%
1
MS2/20
pF
0,1 s
400
V,
d.c. +
a.c. peak
500
kHz
16 divisions
24
divisions
~40ns
40
dB at 1 MHz
-40
dB or
better at 10
MHz
5 0,3 div/hour
Additional
Information
Rectangular tube face, mesh
type,
post
accelerator,
metal backed
phosphor.
1 div. equals 1
cm
P7 (GM) optional
Cont. variable
illumination
Measured
at 8
div. amplitude and
applied rise time
of ~
1 ns.
1-2-5
sequence
Coupling switch to AC
After adjustment at d.c. or low
frequencies
t
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11
1.2.3 Horizontal or
X-axis
Horizontal
deflection can be obtained from either the Main time base or the Delayed time base or a
combi-
nation
of
the
two,
or from the signal source selected for Xdeflection. In
this
case X
-Y
diagrams can be
displayed using A,
B,
the
Ext.
input connector, or line as a signal source for horizontal deflection.
1.2.4
1.2.5
Display modes
Main time base
Operation
Time coefficients
Continuous control range
Coefficient error
Magnification
Magnifier error
Max. effective time
coefficient
Delayed
time
base
Operation
Time coefficients
Continuous control
range
Coefficient error
Delay
time
Incremental
delay
time
accuracy
Delay
time
jitter
—Main
time
base
—Main
time
base intensified
by delayed
time
base
—Main
time
base and delayed
time base alternately
displayed
— Delayed
time
base
—
XY
or
XY/Y
operation
Automatic
Triggered
0,5s/DIV
0,2µs/DIV
1 : > 2,5
±
3%
10x
± 2%
20
ns/DIV
Delayed time
base
either
starts
immediately after
delay
time or
is triggerable
after
the delay time, by the
selected delayed time base
trigger
source
1
mS/DIV —
0,2
µs/DIV
1 :
~ 2,5
± 3%
Insteps
variable with main
time base.
Continuously variable with
10 -turn
potentiometer
between 0
x
and 10 x the
time coefficient
of
the
main time base
0,5%
n : ~ 20.000
X deflection
by:
—
Channel A signal
—
Channel B signal
—
Signal
applied to
EXT connector of
main
time base
—Mains
frequency
Possibility
of
automatic free
-running
in the absence
of triggering signals
1-2-5 sequence
1-2-5 sequence

12
Designation
1.2.6
X
Deflection
Source
Deflection
coefficients
Deflection
accuracy
Frequency
range
Phase
shift
Dynamic
range
1.2.7 Triggering
of the
main time base
Source
Trigger mode
Trigger sensitivity
Triggering frequency
range
Level
range
Triggering slope
Input impedance
Maximum permissible
input voltage
Specification
Additional
information
A, B,
EXT.
or
LINE (MAINS)
As
selected by
trigger source
switch,
if
push-button
X
DEFL.
is
depressed
A, or B: As
selected by
AMPL/DIV
EXTERNAL: 0,5
V/division
LINE:
8
divisions
±10%
inAor6
DC: 0 .... 1
MHz
(-3
dB)
over 6
divisions
S
3 °
at 100
kHz
24
divisions
For
frequencies ~
100
kHz
Ch. A, Ch.
B,
Composite,
External and Line
(mains)
Automatic,
normal AC
normal DC,
TV -line
and
TV frame
Internal:
1,0
div.
External: 0,5
Vpp
AUTO: 20 Hz....~
50
MHz
AC: 50
Hz ~ 50
MHz
DC:OHz
~50MHz
AUTO:
Proportional
to
peak
-to
-peak value
of
trigger
signal.
AC,
DC:
16
div. at
Internal
trigg., and 8
V at
external
trigg.
Positive or
negative going
1
MS2//20
pF
400
V, d.c.
+
a.c.
peak
1.2.8
Triggering
of
the
delayed time base
Source
chA, chB, Composite,
External
1.2.9
+ or
—8
div
and
+
or
—4
V
referenced to
centre
of screen
Other
trigger specifications are
identical to "triggering
of the main
time base"
with the exception
of TV
triggering.
Calibration
generator
Output voltage
Accuracy
Frequency
1,2 Vpp
{' 1
~2kHz
Square
wave
~f
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13
Designation Specification
Additional Information
1.2.10
Power
supply
AC
supply:
Nominal voltage range (on
line -mains
voltage
adaptor)
"'
Nominal
frequency range
Power
consumption
DC supply:
Voltage
range
Current
consumption
...
.~,
:...
1.2.11 Environmental conditions
Double insulated
Safety
class
I I, I EC
348
110, 127, 220 or 240 Vac
± 10%
50
400
H z ±
10%
30
W max. At
nominal
mains
voltage
22-27
V
do Floating input
1,1 A
max.
The environmental data are valid
only if
the
instrument is checked
in accordance with the
offical
checking
procedure. Details on these procedures and
failure criteria are
supplied
on request
by the PHILIPS
organisation in
your country, or by N.V. PHILIPS'
GLOEILAMPENFABRIEKEN, TEST
AND
MEASURING
DEPARTMENT, EINDHOVEN HOLLAND.
Ambient
temperature:
Rated range
of use
+
5 ° C + 40 °
C
Limit range
of operation — 10 ° C +
55 ° C
Storage and transport conditions — 40 °
C
+
70 ° C
Humidity
According to IEC
68
Db
Bump
1000
bumps
of
10
g,'h sine,
6 ms
duration in
each of
3
directions
Vibration 30
minutes in each
of three
directions, 10-150
Hz;
0.7 mm
p -p and 5g max.
acceleration
Altitude:
Operating
5000
m (475 mbar)
Not
operating 15000
m (100
mbar►
Recovery time
30 minutes
if instrument
temperature is
raised from
— 10 ° C to+20 °
Cat
60%
relative
humidity
Electromagnetic
interference The instrument
meets the
VDE, Storgrad K,
requirements
1.2.12
Mechanical data
Dimensions:
Length
420
mm
Width
330 mm
Height
150
mm
Weight
8,4 kg (18,51b)
approx.
1.3
ACCESSORIES
1.3.1 Supplied
with the instrument
Front
cover
-- 2
BNC-4 mm
adaptors
Feet included

14
1.3.2
Optional
Passive
probe
1:1
Passive
probe 10:1
Passive probe
100:1
Miniature Fet
probe
Fet
probe
Current probe
Probe
power supply
Oscilloscope trolley
Polaroid
filter
Viewing
hood
Long
viewing
hood
Oscil loscope
camera
Adaptor for
PM
9380
19 -in
rackmount
Accessory
pouch
Battery pack
PM 9335
(L)
PM
9336
(L►,
PM 9350
(L), or
PM 9351 (L)
PM 9358
PM 9352
PM
9353
PM 9355
PM
9346
PM 8991
PM 8910
PM
9366
PM 8980
PM
9380
PM 8971
PM 8962
PM
8992
PM
8901

15
~` 2.
Directions for
use
2.1
INSTALLATION
2.1.1
Safety
regulations (in
accordance with IEC
348)
Before connecting
the
instrument to the mains (line),
visually check the
cabinet, controls and
connectors
etc.
"` to ascertain
whether any damage
has occurred in
transit.
If
any
defects
are
apparent, do not connect the
instrument to the
mains (line).
The instrument
must be disconnected from all
voltage
sources and any
high
voltage
points discharged before
""` any
maintenance or repair
work is carried out. If
adjustments or
maintenance
of
the operating
instrument
with
covers removed is inevitable,
it must be carried
out only by a skilled person
who is aware of the
hazards
involved. In normal
operation the
double -insulated power supply
obviates the need of
a safety ground.
...,
Warning:
It must be
borne
in
mind that in all
measurements
the frame ground of
the oscilloscope
is
raised to the same
potential as that of
the measuring ground probe
connection. Neither the
probe's ground lead nor
the frame ground shall
be connected
to
live
potentials.
..~ 2.1.2 Local
mains (line)
connection and fuse
protection
Before
connecting the
instrument to the mains (line)
ensure that it is set to the local
mains
(line)
voltage. On
delivery
the
instrument is set to 220 V. If the
instrument is to be used with
110 V,
127
V or 240
V
supply,
_,,, the
appropriate voltage should be
selected by
turning the adaptor on the rear panel
to indicate the voltage
required
(see Fig.2.1).
The
instrument
is protected from
overloads
by
a thermal
fuse fitted between the
mains
(line) transformer
windings. It can be
replaced after having
removed the
instrument
rear panel
(see section
3.2).
-„
Fig. 2.1.
Rear
view of
the oscilloscope showing
the voltage adapter set to 220 V.

16
2.1.3
Connection
to
an
external supply
An
external supply or
battery
of
22
V to 27 V
capable
of delivering at least
1 A
can be
connected to the
socket
on the rear
panel.
The inner
conductor must be
connected to the
negative pole
and the
outer
conductor to the
positive
pole,
as
indicated on
the rear panel.
The instrument is
protected against overloads and
reversed polarity
by an
internal
fuse and diode.
2.1.4
Front
cover and
instrument
position
The front
cover
can
be
simply removed by
pull ing
it
from
the front.
The
instrument may
be used
horizontally or in
several sloping positions
by using
the carrying
handle as a
tilting
bracket.
To
unlock the handle,
simultaneously push in both pivot
centre knobs.
2.2
CONTROLS
AND SOCKETS (Refer to Fig. 2.2)
2.2.1 Cathode-ray
tube and POWER controls
ILLUM
Continuously variable
control of the
graticule illumination;
POWER
ON incorporates mains
(line►
switch.
POWER ON pilot lamp indicates
the
ON state.
INTENS
Continuously variable
control
of
the
trace brilliance.
FOCUS Allows
beam to be
focused for
minimum spot size.
TRACE ROTATION
Screwdriver adjustment to
align the trace
with
the
horizontal
graticule lines.
tNTEN6
FOCUS
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Fig.
2.2.
Front view of the oscilloscope showing controls and sockets.
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17
2.2.2
Vertical channels
Display
mode
switch
A —ALT
—CHOP
—ADD — B
A
Function
5
-way pushbutton switch
selecting the vertical
display mode.
With all
buttons released, the ALT mode
is
in
operation.
Vertical
deflection is achieved by the signal
connected to the input
of
channel A.
ALT
The
display is switched over from
one vertical channel
to
the other
at
the end of
every cycle of the
timebase signal .
CHOP
The
display is switched over from one
vertical channel to the other
at a fixed
frequency.
(f
~
500
kHz)
ADD
Vertical deflection
is achieved by the sum signal of
channels
A
and B.
B
Vertical
deflection is achieved by
the
signal
connected
to the input
of
channel B.
POSITION
Continuously
variable controls giving vertical
shift
of the
display.
PULL
TO INVERT B
Push-pull
switch combined with
the channel B POSITION control.
When pulled, channel B
signal is inverted.
AMPL/DIV
(outer) Step control of
the vertical
deflection coefficients, ranging from
2 mV/div up
to 10
V/div
in a 1-2-5 sequence.
AMPL/DIV
(centre -knob►
Continuously variable control of
the vertical deflection
coefficients.
Note
that the deflection coefficient
is calibrated
only with
the
centre -knob switched
to the
CAL
position (fully -clockwise).
/nputcoup/ingswitch
Signal
coupling; 2 -way pushbutton switch
AC/DC —
0
AC (depressed)
DC (released)
0 (depressed)
A (1MSZ//20pF)
B (1MSZ//20pF)
2.2.3 Horizontal channel
X deflection source
switch
DTB MTB —
XDEFL
~-- A LT
T B --~
Coupling
via a blocking capacitor
Direct coupl ing
Connection
between input circuit and input socket
is
interrupted
and
the input
circuit is grounded.
BNC
socket for channel A input
BNC socket for channel B input
Function
HorizontalcJeflection controls; 3 -way pushbutton switch
DTB
The horizontal
deflection voltage is
suppl
ied by
the
delayed time -
base generator.
MTB
The horizontal
deflection voltage
is
suppl
ied by the main timebase
generator.
A portion of
the trace is intensified
when the delayed
timebase is running.
The delayed
timebase generator is switched off when the
DELD
TIME/DIV switch is in the
OFF
position.
If
no
buttons
are depressed
the effect is the same as the MTB button
depressed (only
the
MTB LEVEL
control is not operating in
this
situation).
DTB
MTB When both the DTB
and MTB
pushbuttons are
selected simultaneously,
LALT TB—~
the
horizontal deflection
voltage is supplied by the main and
delayed
timebases alternately.
X
DEFL
Horizontal
deflection is achieved by an external signal applied
to
the input socket of the horizontal amplifier,
by the
channel A signal,
the
channel B
signal,
or by amains-frequency signal.

18
TIME/DIV (outer switch)
TIME/DIV (inner knob)
X POS/X
MAGN
TRACE
SEP.
2.2.4
Main time base
generator
LEVEL
SLOPE (IN +,OUT—)
Trigger mode
switch
AC —AUTO —
DC
L
TVL~~TVF--~
AUTO
AC
DC
AC
AUTO
LTVL-~
AUTO DC
~- TV
F —I
Continuously variable
control giving
horizontal shift
of the display;
incorporates
apush-pull switch,
PULL FOR
x
10,
which
increases
the horizontal
deflection coefficient
by a
factor
of
10.
The
magnifier
is also
operative
if an
external X deflection
signal is
used.
Continuously variable
control
of
the
vertical space
between the two
time -base displays in
the ALT.TB
mode.
Continuously variable
control to select the
level
of
the
triggering
signal
at
which the
timebase generator starts.
This
control incorporates
apush-pull switch,
which
enables
choice
of
triggering
on the
positive or
negative~oing edge
of
the
triggering
signal.
For TV triggering, select
—for negative video
signals and
+for positive video signals.
Function
3
-way
pushbutton switch selecting the
trigger mode.
With all pushbuttons
released
AUTO
sweep mode is in
operation
at
a fixed range
of the
LEVEL control.
A trace is displayed
in the absence
of trigger signals. The range
of
the
LEVEL control
is
proportional
to the
peak -to -peak value
of the
triggering
signal .
Normal triggering
and fixed
range of the LEVEL control.
The DC
component
of the
trigger signal
is
blocked.
Normal triggering and
fixed range
of
the
LEVEL control. The
DC
component of
the
trigger
signal
is
passed.
Line
synchronisation is
obtained.
Frame synchronisation
is obtained.
Trigger source switch
Function
A —
B
—EXT
—LINE
4
-way
pushbutton
switch
selects
the trigger source, (or the
source
L
COMP —I
of horizontal deflection
if
X deflection
source switch
is
depressed
for X DEFL).
With
al l
pushbuttons
released, the effect is
the same
as
the A
button
depressed.
A
Signal derived from
channel A
B
Signal derived from
channel B
A
6
Composite signal,
derived after
the
electronic switch. Triggering
~—COMPS
occurs
on the
displayed
waveforms
(not usable with X
DEFL).
EXT
External signal derived
via the adjacent 1
MS2//20pF socket.
LINE (MAINS)
Signal derived from the
l
ine
(mains) voltage.
(Inoperable when
instrument is
battery -powered►.
Selects
the time
coefficient
from .2 µs/d
iv
to .5
s/div in
a
1-2-5
sequence.
Continuously variable
control of
the time coefficients.
Must be
switched
to
CAL position (i.e. fully
clockwise)
for
the time
axis to
be calibrated according to the indication
of
the
TIME/DIV switch..
1 MS2 —
20
pF
BNC socket
for external triggering or horizontal deflection.

19
-- 2.2.5 Delayed time
base generator
LEVEL
Continuously variable
control to select
over
a fixed range the
level
SLOPE (IN
+,
OUT —)
of the triggering signal at
which the time base generator
starts.
~-^
This
control
incorporates
apush-pull switch, which
enables
choice
of
triggering
on
the
positive or negative going edge of the triggering
signal.
-.
...
...
.~
..
A
A
1
Trigger
mode
switch Function
AC — DC
2
-way
pushbutton switch selecting the trigger mode
AC
Normal triggering and fixed range
of
the
LEVEL control. The DC
component
of
the trigger signal is blocked.
DC
Normal triggering and fixed
range of
LEVEL control.
The DC
component
of
the
trigger signal
is
passed.
DELAY
TIME Continuously
variable
vernier control
of the
delay
time, together
with the
TIME/DIV controls
of the main time base
generator.
Trigger source switch Function
A — B —EXT —MTB 4 -way pushbutton
switch
selects
the trigger source and starting
point
of
delayed time base. No
pushbutton depressed has the same
effect as the MTB
button depressed.
A Internal triggering
Signal derived from channel A.
B Internal triggering
Signal
derived
from channel
B.
A
B Composite signal, derived after the electronic
channel switch.
~-COMPJ
Triggering occurs on the displayed
waveform, after selected delay
time.
EXT Triggering on an external signal connected to the adjacent
1MS2//20pF
socket.
MTB
Internal triggering
signal
derived
from the main time
base
to
start
the
delayed
time
base immediately after the selected delay
time.
TIME/DIV (outer switch)
Selects the
time
coefficient from 2µs/d
iv
to
1
ms/div in
a 1-2-5
sequence.
Incorporates
an OFF position
by
which
the
delayed
time base
generator is switched
off.
TIME/DIV (inner knob) Continuously
variable
control of
the time
coefficients. Must
be
in
the CALposition (i.e.
fully
clockwise) for the time axis to be
calibrated according to the indication
of
the
TIME/DIV switch.
1 MSZ —
20
pF
BNC socket
for external
triggering
signal .
2.2.6 PAiscellaneous
CAL Output socket supplying squarewave voltage =
2
kHz at an amplitude
of 1.2 V p -p± 1%.
To
be
used
for
probe compensation and/or
checking vertical deflection accuracy.
DC
POWER IN Input
socket at the
rear of
the
instrument allows operation by an
external d.c. supply. Rated supply voltage 22
V
to
27 V,
current
capabil
ity > 1A.
LINE
(MAINS)
VOLTAGE
Must be set according to section 2.1.2 before the instrument is
ADAPTOR connected to the local mains voltage.