Tektronix P6230 User manual

Tektronix, Inc.
P.O. Box 500
Beaverton, Oregon 97077
070-4211-00
Product Group 60
lbktlOl1i»
COII.MTTED 10 EXCELLENCE
PLEASE CHECK FOR CHANGE
INFORMATION AT THE REAR
OF THIS MANUAL.
INSTRUCTION MANUAL
Rrst Printing APR 1983
Revised SEP 1986

Copyright ® 1983 Tektronix, Inc. All rights reserved.
Contents of this publication may not be reproduced in any
form without the written permission of Tektronix, Inc.
Products of Tektronix, Inc. and its subsidiaries are covered
by U.S. and foreign patents and/or pending patents.
TEKTRONIX, TEK, SCOPE.MOBILE, and i! are
registered trademarks of Tektronix, Inc. TELEQUIPMENT
is a registered trademark of Tektronix U.K. Limited.
Printed in U.S.A. Specification and price change privileges
are reserved.
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TABLE OF CONTENTS
Page
LIST OF IllUSTRATIONS .................................................. ..iii
LIST OF TABLES ...................................................................... ..iv
OPERATORS SAFETY SUMMARY ................................... v
SERVICING SAFETY SUMMARY ...................................... vii
SECTION 1 SPECIFICATION
DESCRIPTION ....................................................... 1-1
ACCESSORIES ...................................................... 1-1
PERFORMANCE CONDITIONS ..................... 1-2
SECTION 2 OPERATING INSTRUCTIONS
INTRODUCTION ................................................... 2-1
OPERATING CONSIDERATIONS ................. 2-1
Probe Handling ................................................ 2-1
Probe Grounding ............................................ 2-1
Input Dynamic Range ................................... 2-2
CONTROLS AND CONNECTORS ................ 2-2
PROBE ACCESSORIES .............. " .................... 2-4
OPERATION ........................................................... 2-7
Page
SECTION 3 PERFORMANCE CHECK
PURPOSE ................................................................ 3-1
TEST EQUIPMENT REQUIRED ..................... 3-1
LIMITS AND TOLERANCES ............................ 3-1
PREPARATION ...................................................... 3-1
PROCEDURE STEPS .......................................... 3-3
DC Offset Check ............................................. 3-3
Bandwidth/Rise Time
High-Frequency Aberrations Check
...... 3-5
IWARNING ,
The following servicing instructions are for use
by qualified personnel only. To avoid personal
injury, do not perform any servicing other than
that contained in operating instructions unless
you are qualified
to do so.
SECTION 4 ADJUSTMENT PROCEDURE
PURPOSE ................................................................ 4-1
TEST EQUIPMENT REQUIRED ................... ..4-1
P6230

TABLE OF CONTENTS (cont)
Page
ADJUSTMENT SEQUENCE ........................... ..4-1
ADJUSTMENT LOCATIONS ......................... ..4-1
PREPARATION ...................................................... 4-2
PROCEDURE STEPS
........................................ ..4-4
Check/Adjust Offset Null
.......................... ..4-4
Check/Adjust Attenuation Accuracy
and Mid-Frequency Response
................. 4-4
SECTION 5 THEORY OF OPERATION
GENERAL CIRCUIT DESCRIPTION ............ 5-1
DETAILED CIRCUIT DESCRIPTION ............ 5-1
SECTION 6 MAINTENANCE
INTRODUCTION ................................................... 6-1
STATIC-SENSITIVE COMPONENTS .......... 6-1
PREVENTIVE MAINTENANCE ....................... 6-3
Cleaning .............................................................. 6-3
Visual Inspection ............................................ 6-4
Semiconductor Checks ............................... 6-4
TROUBLESHOOTING ........................................ 6-5
Schematic Diagram and Circuit
Board Illustration
............................................ 6-9
Page
Color Codes and Markings ........................ 6-9
Semiconductor Lead Configuration ....... 6-9
Troubleshooting Techniques .................... 6-9
CORRECTIVE MAINTENANCE ...................... 6-13
Maintenance Precautions ........................... 6-13
Obtaining Replacement Parts .................. 6-13
Soldering Techniques .................................. 6-14
PROBE DISASSEMBLY .................................... 6-16
Probe Tip Replacement ............................... 6-16
Control Box Disassembly ........................... 6-16
Cable Assembly Replacement ................. 6-1 8
Input Power Connector ReplacemenL6-18
INT-EXT Switch Replacement.. ................ 6-18
READJUSTMENT AFTER REPAIR ............... 6-20
INSTRUMENT REPACKING ............................ 6-20
SECTION 7 REPLACEABLE PARTS
DIAGRAMS
REPLACEABLE ELECTRICAL PARTS
REPLACEABLE MECHANICAL PARTS
OPTIONAL ACCESSORIES
ii
P6230
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Figure
1-1
2-1
2-2
2-3
2-4
2-5
3-1
4-1
5-1
LIST OF ILLUSTRATIONS
Page
P6230 Probe ............................................................ viii
Typical input impedance versus
frequency
................................................................... 1-6
Controls and connectors ................................... 2-3
Installation of probe accessories
................ .2-5
Simplified functional diagram ......................... 2-7
Typical
ECl output circuit... ............................ .2-8
Typical loading effects
on ECL.. .................... 2-8
High frequency check setup
........................... 3-6
P6230 adjustment locations ......................... ..4-5
Functional block diagram
.................................. 5-2
Figure
6-1
6-2
6-3
6-4
6-5
7-1
7-2
7-3
7-4
7-5
P6230
Page
Lead configuration of IC .................................... 6-9
Color code for resistors
and capacitors ........................................................ 6-10
Disassembly of control box .............................. 6-17
Input power connector pins ............................. 6-18
I NT -EXT switch removal .................................... 6-19
Schematic diagram for the P6230
P6230 circuit board
Exploded view
Accessories
Optional accessories
iii

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LIST OF TABLES
Table Page
1-1 Electrical Characteristics .................................. 1-2
1-2 Environmental Characteristics ....................... 1-5
1-3 Physical Characteristics
.................................... 1-5
2-1 Typical Performance Effects
of Grounding Configurations ........................... 2-6
3-1 Test Equipment Required
................................. 3-2
4-1 Test Equipment Required ............................... ..4-2
6-1
6-2
6-3
Relative Susceptibility To Static
Discharge Damage ................................................ 6-2
Troubleshooting Equipment ............................ 6-5
Fault Indication and Probable Cause ......... 6-6
P6230

OPERATORS SAFETY SUMMARY
The general safety information in this part of the summary is for both operating and servicing personnel. Specific
warnings
and cautions will be found throughout the manual where they apply, but may not appear in this sum-
mary.
Terms In This Manual
CAUTION statements identify conditions or practices
that could result
in damage to the equipment or other
property.
WARNING statements identify conditions or practices
that could result
in personal injury or loss of life.
Do Not Operate In Explosive Atmospheres
To avoid explosion, do not operate this product in any
explosive atmosphere unless it has been specifically
certified for such operation.
Do Not Remove Covers
To avoid personal injury, do not remove the product
covers.
Do not operate the product without the covers
properly installed.
P6230
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SERVICE SAFETY SUMMARY
FOR QUALIFIED SERVICE PERSONNEL ONL Y
Refer also to the preceding Operators Safety Summary.
Do Not Service Alone
Use Care When Servicing With Power On
Do not perform internal service or adjustment of this pro-
duct unless another person capable of rendering first aid
and resuscitation is present.
To avoid personal injury. do not touch exposed con-
nections and components while power is on.
REV MAR 1986
P6230
vii
$ M.%Q.. MiA

The P6230 Probe.
viii

SPECIFICATION
DESCRIPTION
The TEKTRONIX P6230 is a low-impedance, sub-
miniature, 10X active probe for use with broad-band
oscilloscopes. The P6230 is equipped with an
internal/external 50-ohm termination switch which
al-
lows the probe to be used on scopes having an input
resistance of either
50n or 1 Mn. A coding pin on
the BNC connector advances the Volts/Division read-
ing by 10X, on oscilloscopes equipped with this
feature, so that the correct deflection factor at the
probe tip is indicated.
The compensation box of the
P6230 houses an ac-
tive circuit which provides a variable voltage at the
probe tip, This voltage is used to minimize probe-
loading effects. The voltage available at the tip of the
P6230 spans the range from -5 volts to +5 volts, al-
lowing the probe to minimize loading effects on most
logic families that are in use today.
The P6230 is available with a 1.6-meter Signal
ca-
ble and a 1 A-meter power cable.
The subminiature probe head of the P6230 is fully
compatible with the Tektronix family of subminiature
probe accessories.
ACCESSORIES
The P6230 is shipped with the following standard
accessories:
Instruction manual
1 Carrying pouch
1 Hook tip
2 Circuit-board-to-probe-tip connectors
1 Ground lead with microhook
1 Low-inductance ground lead
1 Ground lead with alligator clip
1 Probe holder
4 Sets of cable markers (2 each: white, gray, red,
green)
Use of these accessories is described in the
"Operating Instructions" section of this manual. Part
numbers and optional accessories are listed in the
"Replaceable Parts List" (Section 7).
Section 1 - P6230
1-1

PERFORMANCE CONDITIONS
The electrical characteristics listed in Table 1-1
apply when a calibrated probe is used with a calibrat-
ed oscilloscope system operating within the environ-
mental conditions stated in Table 1-2.
Items listed in the "Performance Requirement"
column are verifiable qualitative or quantitative limits.
Items listed in the "Supplemental Information" column
are not verified in the "Performance Check Pro-
cedure" (Section 3); they are either explanatory
notes, calibration setup descriptions, performance
characteristics for which no absolute limits are
specified, or characteristics that are impractical to
check.
The probe's physical characteristics are listed in
Table 1-3.
Table 1-1
Electrical Characteristics
Characteristic Performance Requirement Supplemental Information
Attenuation 10X ±3% at dc. Probe terminated by son ±O.5%.
(system)
Input Resistance 4500 ± 1% at dc.a Probe terminated by son ±O.5%.
(system)
Input Capacitance Less than 1.6
pF.
a Typically 1.3
pF. See Figure 1-1 for
(1 kHz to 1.5 GHz) a graph of input impedance
versus frequency.
a Performance Requirement not checked in manual.
1·2
Specification - P6230
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Characteristic
Bandwidth (-3dB)
(Probe only)
Rise Time
(Probe only)
Aberrations
(Probe only)
Signal Delay
Input Dynamic Range
Offset Null
DC Offset Range
DC Thermal Drift
• PerfOI'llMlRCe Requirement not checked In manual.
REV MAR 1986
Table 1-1 (cont)
Electrical Characteristics
Performance Requirement
DC to at least 1.S GHz.
Less than 230 ps.
Less than +4%, -6%,9% p-p for the
1st 1 ns; ±3% thereafter.
8.70 ns ± 100 ps.a
-S V =E;; (VsIgnaI + VottseJ =E;; +S V.
Less than ±10 mV.
oto at least +S V and -5 V.
Less than 10 mV/hr/oC.a
Specification - P6230
Supplementallnfonnation
Calculated from probe rise time:
BW = 0.3S/rise time
Test system must have a rise time of
less than 100 ps.
In addition to system aberrations.
Probe tip to output BNC.
Measured from probe tip to ground with
a high impedance (~ 50k ON)
voltmeter.
Equivalent input offset voltage.
1-3
¥ 4 4. ~,
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Characteristic
Output
load Requirement
Maximum Nondestructive Input Voltage
Power Supply Requirements
• Performance Requirement not checked in manual.
1·4
Table 1·1 (cont)
Electrical Characteristics
Performance Requirement
50 n ± 0.5%.8
'0 Vdc continuous, 30 V (dc + peak
ac) for 1 sec.a
Tektronix Oscilloscope Probe Power
Supply.
Specification - P6230
Supplemental Information
+15 Vdc ±40/0.
-15 Vdc ±4%.
less than 10 mV ripple (20 Hz to
500 Hz).
REV MAR 1986

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Table 1·2
Environmental Characteristics
Characteristic
Temperature Range
(Operating)
Temperature Range
(Nonoperating)
Humidity
Altitude
(Operating)
Transportation
Information
O°C to +50°C
(+32"F to +122"F).
-55OC to +75°C
(--67°F to +167"F).
Five cycles (120 hr.)
at 90% to 95% relative
humidity at 30°C to 60°C.
To 4,600 m (15,000 tt).
Qualifies under
National Safe Transit
Association's
Pre-Shipment Test
Procedures; 1A-B-1.
Table 1·3
Physical Characteristics
Characteristic
Net Weight (includes
accessories)
Signal Cable Length
Power Cable Length
Information
400 g (14 oz).
1.6 m
(61 in).
1
.4 m (54 in).
Specification - P6230
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(0)
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(0)
600
450
100
10
+50
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-50
100 kHz 1 MHz
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10 MHz
FREQUENCY (Hz)
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100 MHz
Figure 1-1. Typical input impedance versus frequency.
Specification - P6230
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4211-02A
REV MAR 1986

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1
OPERATING INSTRUCTIONS
INTRODUCTION
This section of the manual is intended to familiar-
ize the operator with the use of the P6230 Probe. In-
cluded are operating considerations, descriptions of
the controls and connectors, instructions for the use
of the accessories, and a description of the use and
operation of the probe.
NOTE
The P6230 is shipped in a carton along with
its standard accessories. At installation time.
save the shipping carton and packaging ma-
terials for reuse should reshipment become
necessary. Refer to "Maintenance" (Section
6) for further information.
OPERATING CONSIDERATIONS
Probe Handling
The P6230's subminiature body has been
designed for ease of use when probing small circuitry.
Both the probe itself and its accessories should be
handled carefully at all times.
To prevent damage,
avoid dropping the probe body. since damage to its tip
may result. Exercise care to prevent crushing the ca-
ble or placing excessive strain
on it by pulling.
Probe Grounding
A probe is a capacitive divider for high-frequency
signal components. Inductance introduced
by either a
long signal lead or ground lead will form a series-
Section 2 - P6230

resonant circuit that can distort the true waveform or
degrade the bandwidth. The ground lead and signal-
input connections should be kept as short as possible
to maintain the best waveform fidelity.
Input Dynamic Range
The input dynamic range of the P6230 is limited by
the ability
of the internal amplifier to drive the 50n
termination. This limitation exists whether the input
signal originates at the probe tip (test signal) or the
internal offset voltage. Therefore, the limitation on the
signal that can be applied to the probe tip is depen-
dent on the amount of offset voltage being used.
To
maintain signal fidelity, the test signal should not
exceed the limits imposed by the following formula:
-5.0 V ~ (V . +V ) <: + 50 V
signal offset voltage -- .
DESCRIPTION OF CONTROLS AND CONNECTORS
The following information will familiarize the opera-
tor with the location and function of the external con-
trols and connections of the P6230. Please refer to
Figure 2-1.
G) Input Power Connector -Connects the probe to
the probe power receptacle on either
the oscillo-
scope mainframe or an accessory power supply.
®INPUT BIAS/OFFSET VOLTAGE -Continuously
variable control that sets the level of the voltage
supplied to the probe tip.
® INT-EXT Switch -Selects the source of the 50-
n load required by the output of the P6230.
INT -A precision 50-n resistor is internally
2-2
Operating Instructions - P6230

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4211-03
Figure 2-1. Controls and connectors.
connected across the output of the P6230.
This selection is used
when the probe is con-
nected to
an instrument havjng an input im-
pedance of 1 MO or greater.
EXT -The internal load is removed from the
output of the P6230.
This position should be
used
when the probe is connected to an in-
strument that has an input impedance of 500
±0.5% available.
@Output BNC - Used for connecting the output of
the P6230 to the input of
an oscilloscope or oth-
er test instrument.
@ Probe Tip -Used to apply the test signal to the
probe/instrument system.
@ Ground Lead Socket -Used to connect the
standard-accessory ground leads.
oReadout Connector -The spring-loaded contact
finger actuates the readout circuitry of oscillo-
scopes equipped with this feature.
When the
Operating Instructions - P6230
2·3

probe is attach'ed to the input connector of the
oscilloscope, the Volts/Division reading will au-
tomatically advance by 10x so that the correct
deflection factor at the probe tip is indicated.
PROBE ACCESSORIES
Both standard and optional accessories for the
P6230 are listed in the "Replaceable Parts List" near
the back of this manual. Standard accessories are
supplied to aid in connecting the probe to circuitry
under test and to protect the probe against damage.
These accessories are described
in the following
paragraphs and are illustrated in Figure 2-2.
Probe Holder
Each probe holder provides a convenient means of
storing two probes
in a readily accessible location.
The holder has adhesive on the rear side to enable
attaching it to an oscilloscope. To install the holder,
peel off the protective covering from the adhesive and
attach the holder to the cabinet side, preferably near
the vertical inputs. For maximum strength, the holder
should be left to set for 4B hours before inserting any
probes. When a probe is not in use, insert its tapered
portion (behind the probe head) into the holder,
Ground Leads
The P6230 Probe is supplied with three ground
leads: a 150-mm (5.S-in) lead with a microhook, a
250-mm (S.B-in) lead with an alligator clip, and a 40-
mm U.6-in) low-inductance lead. To minimize distor-
tion, always use the shortest possible ground lead.
Refer to Table 2-1 for typical effects on performance
for the various grounding configurations. Each
ground lead is equipped with a square-pin connector
which plugs into the socket in the probe's grounding
collar.
Before using the low-inductance lead, remove the
light-grey probe-body shell and flip the grounding col-
lar so that the socket faces toward the probe tip. Then
replace the probe body shell and install the ground
lead (see Figure 2-2).
2-4 Operating Instructions - P6230
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