Tektronix TG501 User manual

Tektronix, Inc.
P.O. Box 500
Beaverton, Oregon
INSTRUCTION MANUAL
97005 Serial Number
070-1576-00 1073

WARRANTY
All -TEKTRONIX instruments- are .warranted: against
defective materials and workmanship for one year. Any
questions with reflect tojfhe warranty diould he taken up
with your TEKTRCWdX IFreW Engineer or representative.
AH requests for repair and repjacement.parts should .he
directed to the TEKTRONIX Field Office or represented^
in your area. This" will assure you the"' fastest i»ssiiM
service. Please include the instrument Type Number or Fart
Number and Serial Nunyber with all reques|s
service. .
>-• ..ts!rJ, ,
Specifications and price change privileges reserved.
Copyri^t ©1973 by Tektronix, Inc., Beaverton, Oregon.
Printed in the United States of America. All rights reserved.
Contents of this publication may not be reproduced in any
form without permission of Tektronix, Inc.
U.S.A. and Foreign TEKTRONIX products covered by U.S.
and foreign patents and/or patents pending.
TEKTRONIX is aregistered trademark of Tektronix, Inc.

Section 1—TG 501
OPERATING
INSTRUCTIONS
INTRODUCTION
Description
The TG 501 is ageneral purpose Time Mark Generator
plug-in designed to operate in aTM 500 Series Power
Module. AVariable Timing Readout provides asimple, but
accurate means of measuring timing errors over ±7.5%
minimum range. Since many specifications are given in
percentages, the error readout eliminates the need for
computations and, additionally, lessens parallax discrep-
ancies.
Marker selection from 5sthrough 1ns in a1,2,5,
sequence is available. 5sthrough 10 ns markers are selected
by arotary switch. 5,2, and 1ns modified sine waves are
selected by self-canceling push-buttons when the rotary
switch is in the 52 IN position.
All outputs are available at the front-panel connectors or
by modification of the interface connector, located at the
back of the plug-in, and the TM 500 Series Power Module.
Power supplies are current limited. The 5volt supply is
over-voltage protected to avoid damage to the integrated
circuits.
Installation
The TG 501 is calibrated and ready for use when
received. Referring to Fig. 1-1, install the Generator and
turn on the Power Module. Check the front-panel of the
Generator to see that the knob skirt is lighted. The TG 501
is designed to operate in any compartment of aTM 500
Fig. 1-1. Plug-in Installation and Removal.
@1-1

Operating Instructions—TG 501
Series Power Module. Refer to the Power Module Instruc-
tion Manual for line voltage requirements and Power
Module operation.
NOTE
It is recommended that the Power Module be turned
off before inserting or removing the TG 501. Arcing
at the connector terminals can reduce connector life.
However, no interna! damage will result if the
Generator is inserted into alive Power Module.
Refer to the Controls and Adjustments fold out page for
front-panel controls, connectors and indicator descriptions.
OPERATING CONSIDERATIONS
The internal reference of the TG 501 is a1MHz crystal.
If Option 1is ordered, ahigh accuracy 5MHz crystal is
provided and Integrated Circuit, U50 is installed on the
back of the main circuit board. Provisions are made for
buffered output of either 1MHz or 5MHz internal clock
through interface connector pin 25A with associated
ground on pin 26A.
A1MHz, 5MHz or 10 MHz external clock can be
substituted. To use an external 5or 10 MHz clock, U50
must be installed on the back of the main circuit board and
the necessary jumpers added (see Fig. 1-2) to divide down
the input to meet the 1MHz internal requirement. U50 is
not required for a1MHz external clock, but jumpers must
be added.
*^ig. 1-2. Locat'or o* Jumpers and Integrated Circuits required for various c'ock choices.
1-2

Operating Instructions—TG 501
Remove U100 before using external clocks. Interface
connector pin 24B is used for External Clock Input with
the associated ground on pin 25B. Fig. 1-2 shows the
location on the main circuit board of the jumpers that must
be installed to use the TG 501 with the various clock
choices. The required jumpers are:
Standard Internal Reference
1MHz Crystal No jumpers required
Buffered Output of Internal
Clocks
External 1MHz clock
(Remove U100)
External 5MHz clock
(Remove U100, Add U50)
External 10 MHz clock
(Remove U100, Add U50)
Install J2
Install J1, J5
Install J1, J4, J7
Install J1, J4, J6
OPERATING MODES
Calibrated Mode
When center-button of VARIABLE TIMING Control is
pushed in, the MARKER Control selects calibrated marker
intervals from 5sto 10 ns indicated by the lighted knob
skirt. To select 5, 2or 1ns modified sine wave markers, set
MARKER Control to 52 IN position and depress desired
pushbutton.
Variable Timing Mode
When center button of VARIABLE TIMING Control is
out, output timing is faster or slower than the calibrated
marker to the percentage indicated by the VARIABLE
TIMING READOUT Display and the FAST-SLOW Indica-
tor lights. 5, 2and 1ns push-button controlled modified
sine waves are not variable and Readout Display is turned
off when MARKER Control is in 521N position.
Readout Display Test
To check the operation of the display LED's (Light-
Emmiting Diodes), fully depress the center button of the
VARIABLE TIMING Control (push in firmly). All LED
segments should light, displaying 8.8 in the Readout.
TYPICAL APPLICATIONS
The TG 501 can be used for many applications not
described in the manual. Use the following examples to
become familiar with the TG 501's VARIABLE TIMING
READOUT. Contact your Tektronix Field Office or rep-
resentative for making specific measurements with this
instrument.
Time Base Measurements
To accurately determine the timing error of atime base:
1. Connect the MARKER OUT of the TG 501 to the
Vertical Input of the oscilloscope. Use a50 coaxial cable
terminated into 50 SI.
2. connect the TRIGGER OUT of the TG 501 to the
External Trigger Input of the time base. Use a50 S2 coaxial
cable terminated into 50 S2.
3. Select external trigger source on the time base.
4. Select, for example, 1jjis sweep rate of the time base.
5.
Set MARKER Control rotary switch of TG 501 to
1/is.
6.
Make sure center button of VARIABLE TIMING
Control, concentric with MARKER Control, is out (Vari-
able Timing Mode).
7.
Use Horizontal Position control of time base to make
first time mark coincide with first graticule line on the
oscilloscope. See Fig. 1-3.
8.
Rotate VARIABLE TIMING knob until all time
markers coincide with graticule lines on the oscilloscope, as
shown in Fig. 1-4.
1-3

Operating Instructions-TG 501
Make first time
marker coincide
with first grati-
cule line.
Fig. 1-3. Timing Error of Time Base.
9.
Either the FAST or SLOW Indicator will light
showing whether the time base is faster or slower than the
calibrated markers of the TG 501. Read the percentage of
error from the VARIABLE TIMING READOUT Display.
Pulse Generator Measurements
To accurately determine pulse duration or period of a
Pulse Generator.
1.
Adual-trace vertical oscilloscope is required. Select
alternate mode.
2.
Connect the MARKER OUT of the TG 501 to one
channel of the dual-trace oscilloscope. Use a50 coaxial
cable terminated into 50 L2.
3.
Connect the Output of the pulse generator to the
other channel of the dual-trace, using a50 coaxial cable
terminated into 50 i2.
4.
Set the time/div switch to display 1cycle of apulse
in 10 divisions of the graticule on the oscilloscope, as
indicated in Fig. 1-5.
5.
Use the MARKER Control switch of the TG 501 to
display one time marker approximately at pulse duration
Rotate VARIABLE TIMING
knob until all markers coincide
with graticule lines.
Fig. 1-4. Measuring Timing Error of Time Base.
and one at pulse period. Align first time marker with
beginning of pulse wave-form. See Fig. 1-5.
6.
Select Variable Timing Mode on the TG 501, VARI-
ABLE TIMING Control center button out.
7.
Use the Vertical Position control of the oscilloscope
to set the peaks of the time markers at 50% amplitude of
pulse shown in Fig. 1-5.
8.
To check the timing of pulse duration, rotate the
VARIABLE TIMING knob until time marker coincides
with pulse duration, as shown in Fig. 1-6.
9. Either the FAST or SLOW Indicator will light,
showing whether the pulse duration of the pulse generator
is faster or slower than the calibrated time mark of the
TG 501 .Read the percentage of error from the VARIABLE
TIMING READOUT Display.
10. To check the timing of pulse period, rotate the
VARIABLE TIMING knob until time marker coincides
with pulse period. See Fig. 1-7.
11.
Read the VARIABLE TIMING READOUT Display
and check the FAST-SLOW Indicators as described in step
9to find the percentage of error from standard timing.
1-4

Operating Instructions—TG 501
Fig. 1-5. Markers approximately at pulse duration and period.
Fig. 1-6. Measuring Pulse Duration. Fig. 1-7. Measuring Pulse Period.
REAR INTERFACE
Unused pins are available at the rear connector for
routing signals to and from the TG 501 for specialized
applications (see Rear Connector Pin Assignments in
Section 2). One or more compartments of amulti-plug-in
®
Power Module can be wired with barriers installed to
provide specific functions between compartments. See
Power Module instruction manual for additional informa-
tion.
1-5

Operating Instructions—TG 501
APower Module mainframe option (Option 2) is
available which provides arear-panel, multi-pin connector
to which I/O lines can be hard-wired for external access.
Also possible are intra-compartment connections with other
plug-in modules in multiple-compartment mainframes.
SPECIFICATIONS
The electrical specifications are valid only if (1) the
instrument has been calibrated at an ambient temperature
between -t20°C and -h 30°C; (2) the instrument is operating
at an ambient temperature between 0°C and -t50°C, unless
otherwise noted; (3) plug-in must be operating (fully
installed) in acalibrated system.
Any conditions that are unique to aparticular specifica-
tion are stated as part of that specification.
TABLE 1-1
ELECTRICAL CHARACTERISTICS
Characteristics Performance Requirements Supplemental Information
Markers 5sthrough 1ns in a1,2,5 sequence 5sthrough 10 ns are selected by arotary
switch. 5ns, 2ns and 1ns are pushbutton
selected modified sine waves
Marker Amplitude >1 Vpeak on 5sthrough 10 ns markers.
>750 mV peak-to-peak into 50 on 5ns and
2ns markers. >200 mV peak-to-peak into 50
on 1ns markers.
Trigger Output Signal Slaved to marker output from 5sthrough
100 ns. Remains at 100 ns for all faster markers
>1 Vpeak into 50 S2
Internal Reference
Crystal Frequency
Standard Option 1
1MHz 5MHz
Stability (20°C to 50°C) after 1/2 hour
Warm-Up Within 1part in 10’ Within 5parts in 10^
Long-Term Drift 1part or less in 10’ 1part or less in 10''
per month per month
Accuracy Adjustable to within Adjustable to within
1part in 10' 5parts in 10’
External Reference Input (Available
Only if U50 and jumpers are installed
and U100 is removedi
1C and jumpers for 5or 10 MHz, 1MHz
external reference requires jumpers only
Acceptable Frequencies 1MHz, 5MHz, or 10 MHz Internally hard wired so output frequencies
counted down to 1MHz
Input Amplitude Must be TTL compatible
Error Readout Range To ±7.5%
Error Readout Resolution To 0.1% Least significant digit counted is 0.01% and is
rounded off between 5and 6providing amore
accurate error readout resolution (±0.07% of
L.S.D.I
1-6 REV. FEB 1974

Operating Instructions—TG 501
TABLE 1-2
ENVIRONMENTAL CHARACTERISTICS
Characteristics Performance Requirements Supplemental Information
Temperature
Operating 0°C to +50° C
Storage -40°Cto +75°
Altitude
Operating To 15,000 feet
Storage To 50,000 feet
Vibration
Operating and Non-
Operating
With the instrument complete and op-
erating, vibration frequency swept from 10
to 50 to 10 Hz at 1minute per sweep.
Vibrate 15 minutes in each of the three
major axes at 0.015" total displacement.
Hold 3minutes at any major resonance, or
if none, at 50 Hz. Total time, 54 minutes
Shock
Operating and Non-
Operating 30 g's, 1/2 sine, 11ms duration, 2shocks in
each direction along 3major axes, for a
total of 12shocks
Transportation Qualified under National Safe Transit Com-
mittee Test Procedure 1A, Category II
1-7

Section 2—TG 501
SERVICE
INFORMATION
SYMBOLS AND REFERENCES DESIGNATORS
Electrical components shown on the diagrams are in the following units unless noted otherwise:
Capacitors =Values one or greater are in picofarads (pF).
Values less than one are in microfarads (/:tF).
Resistors =Ohms (fi)
Symbols used on the diagrams are based on ANSI Y32.2 —1970.
Logic symbology is based on Ml L-STD-806B in terms of positive logic. Logic symbols depict the logic function performed
and may differ from the manufacturer's data.
The following special symbols are used on the diagrams:
External Screwdriver adjustment.
External control or connector.
Clockwise control rotation in direction of arrow.
Refer to diagram number indicated in diamond.
Refer to waveform number indicated in hexagon.
Connection soldered to circuit board.
Connection made to circuit board with interconnecting pin.
Blue tint encloses components located on circuit board.
P/0 circuit board