Tektronix TCA75 User manual

Instructions
TCA75
75 to 50 Ohm Impedance Conversion Adapter
071-1192-00
*P071119200*
071119200
There are no current European directives that
apply to this product. This product provides cable
and test lead connections to a test object of
electronic measuring and test equipment.
Warning
The servicing instructions are for use by qualified
personnel only. To avoid personal injury, do not
perform any servicing unless you are qualified to
do so. Refer to all safety summaries prior to
performing service.
www.tektronix.com

Copyright ©Tektronix, Inc. All rights reserved.
Tektronix products are covered by U.S. and foreign patents, issued and pending. Information in this publication supercedes
that in all previously published material. Specifications and price change privileges reserved.
Tektronix, Inc., P.O. Box 500, Beaverton, OR 97077
TEKTRONIX and TEK are registered trademarks of Tektronix, Inc., and TekConnect is a trademark of Tektronix, Inc.

WARRANTY
Tektronix warrants that the products that it manufactures and sells will be free from defects in materials and
workmanship for a period of one (1) year from the date of shipment. If a product proves defective during this
warranty period, Tektronix, at its option, either will repair the defective product without charge for parts and labor,
or will provide a replacement in exchange for the defective product.
In order to obtain service under this warranty, Customer must notify Tektronix of the defect before the expiration
of the warranty period and make suitable arrangements for the performance of service. Customer shall be
responsible for packaging and shipping the defective product to the service center designated by Tektronix, with
shipping charges prepaid. Tektronix shall pay for the return of the product to Customer if the shipment is to a
location within the country in which the Tektronix service center is located. Customer shall be responsible for
paying all shipping charges, duties, taxes, and any other charges for products returned to any other locations.
This warranty shall not apply to any defect, failure or damage caused by improper use or improper or inadequate
maintenance and care. Tektronix shall not be obligated to furnish service under this warranty a) to repair damage
resulting from attempts by personnel other than Tektronix representatives to install, repair or service the product;
b) to repair damage resulting from improper use or connection to incompatible equipment; c) to repair any
damage or malfunction caused by the use of non-Tektronix supplies; or d) to service a product that has been
modified or integrated with other products when the effect of such modification or integration increases the time
or difficulty of servicing the product.
THIS WARRANTY IS GIVEN BY TEKTRONIX IN LIEU OF ANY OTHER WARRANTIES, EXPRESS
OR IMPLIED. TEKTRONIX AND ITS VENDORS DISCLAIM ANY IMPLIED WARRANTIES OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. TEKTRONIX’
RESPONSIBILITY TO REPAIR OR REPLACE DEFECTIVE PRODUCTS IS THE SOLE AND
EXCLUSIVE REMEDY PROVIDED TO THE CUSTOMER FOR BREACH OF THIS WARRANTY.
TEKTRONIX AND ITS VENDORS WILL NOT BE LIABLE FOR ANY INDIRECT, SPECIAL,
INCIDENTAL, OR CONSEQUENTIAL DAMAGES IRRESPECTIVE OF WHETHER TEKTRONIX OR
THE VENDOR HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES.

TCA75 Impedance Adapter Instructions i
General Safety Summary
Review the following safety precautions to avoid injury and prevent damage to
this product or any products connected to it. To avoid potential hazards, use this
product only as specified.
Ground the Product. This product is indirectly grounded through the grounding
conductor of the mainframe power cord. To avoid electric shock, the grounding
conductor must be connected to earth ground. Before making connections to the
input or output terminals of the product, ensure that the product is properly
grounded.
Observe All Terminal Ratings. To avoid fire or shock hazard, observe all ratings
and markings on the product. Consult the product manual for further ratings
information before making connections to the product.
The common terminal is at ground potential. Do not connect the common
terminal to elevated voltages.
Do Not Operate Without Covers. Do not operate this product with covers or panels
removed.
Do Not Operate With Suspected Failures. If you suspect there is damage to this
product, have it inspected by qualified service personnel.
Do Not Operate in Wet/Damp Conditions.
Do Not Operate in an Explosive Atmosphere.
Keep Product Surfaces Clean and Dry.
ToAvoidFireor
Personal Injury

General Safety Summary
ii TCA75 Impedance Adapter Instructions
Terms in this Manual. These terms may appear in this manual:
WARNING. Warning statements identify conditions or practices that could result
in injury or loss of life.
CAUTION. Caution statements identify conditions or practices that could result in
damage to this product or other property.
Terms on the Product. These terms may appear on the product:
DANGER indicates an injury hazard immediately accessible as you read the
marking.
WARNING indicates an injury hazard not immediately accessible as you read the
marking.
CAUTION indicates a hazard to property including the product.
Symbols on the Product. The following symbol may appear on the product:
CAUTION
Refer to Manual
Symbols and Terms

TCA75 Impedance Adapter Instructions iii
Contacting Tektronix
Phone [phone]*
Address Tektronix, Inc.
Department or name (if known)
14200 SW Karl Braun Drive
P.O. Box 500
Beaverton, OR 97077
USA
Web site www.tektronix.com
Sales support 1-800-833-9200, select option 1*
Service support 1-800-833-9200, select option 2*
Technical support Email: [e-mail]
1-800-833-9200, select option 3*
6:00 a.m. -- 5:00 p.m. Pacific time
*This phone number is toll free in North America. After office hours, please leave a
voice mail message.
Outside North America, contact a Tektronix sales office or distributor; see the
Tektronix web site for a list of offices.

Contacting Tektronix
iv TCA75 Impedance Adapter Instructions

TCA75 Impedance Conversion Adapter Instructions 1
TCA75 Impedance Conversion Adapter
The TCA75 (Figure 1) is a 75-to 50 Ωimpedance conversion adapter with a very
low VSWR (voltage standing-wave ratio). The adapter allows you to connect
video and communication signals from a 75 Ωsource to the 50 Ωinput of
oscilloscopes equipped with the TekConnect interface, while minimizing
aberrations and reflections. The TCA75 adapter fully complies with ANSI
T1.102 and ITU-T G.703.
Front view
Figure 1: TCA75 Adapter
CAUTION. The TCA75 adapter contains components that are sensitive to
electrostatic discharge (ESD). To avoid electrostatic damage, observe ESD
precautions when handling the adapter.
Standard Accessories
Table 1 lists the standard accessories included with the adapter.
Table 1: Standard accessories
Description Tektronix part number
Instruction Manual 071-1192-XX

TCA75 Impedance Conversion Adapter
2TCA75 Impedance Conversion Adapter Instructions
Connecting the TCA75 Adapter to the Host Instrument
The output of the TCA75 adapter connects directly to the TekConnect interface
on Tektronix TDS6000, TDS7000, and CSA7000 Series oscilloscopes, as shown
in Figure 2. The TCA75 is not compatible with oscilloscopes that do not have
the TekConnect interface. The shell of the input on all oscilloscopes must
connect to earth ground.
The TCA75 adapter connects to the host instrument through the TekConnect
interface. The TekConnect interface features a spring-loaded latch that indicates a
reliable connection has been made to the TekConnect host instrument. Slide the
TCA75 adapter into the TekConnect receptacle on the host instrument. The unit
snaps into the host instrument when fully engaged.
NOTE. After connecting the adapter to the oscilloscope, run the Probe Calibra-
tion Routine described on page 11 to ensure accurate measurements.
To release the TCA75 adapter from the host instrument, grasp the adapter,
depress the latch button, and pull it out of the TekConnect receptacle.
Tektronix TDS6000, TDS7000, and
CSA7000 Series Oscilloscopes
TekConnect interface
75 ΩBNC Male to BNC Male
TCA75
To 75 Ωcircuit 75 ΩBNC input
Latch button
Figure 2: Connecting the adapter to oscilloscopes with the TekConnect interface

TCA75 Impedance Conversion Adapter
TCA75 Impedance Conversion Adapter Instructions 3
Input Signal Connections
The 75 Ωfemale BNC input of the TCA75 adapter accepts a 75 Ωmale BNC
connector. The signal input cable (source) must be 75 Ω. See Table 2 for typical
75 Ωsignal sources.
Table 2: Input signal connections
Impedance Standard Data rate Mb/s)
75 ΩD-1 270
D-2 143
DS-3 44.736
DS-4 139.264
STS-1 51.84
STS-3/STM-1 155.51
E-2 8.448
E-3 34.368
E-4 139.264
SMPTE 259M 270, 360
SMPTE 292M 1.485 Gb/s

TCA75 Impedance Conversion Adapter
4TCA75 Impedance Conversion Adapter Instructions
Specifications
This section contains the specifications and compliances for the TCA75
Impedance Adapter. All specifications are guaranteed unless noted as typical.
Typical specifications are provided for your convenience but are not guaranteed.
Specifications that are marked with the nsymbol are checked in the Perfor-
mance Verification on page 7.
Specification1/compliance Description
Communication and video standards D-1 (270 Mb/s) E-2 (8.448 Mb/s)
D-2 (143 Mb/s) E-3 (34.368 Mb/s)
DS-3 (44.736 Mb/s) E-4 (139.264 Mb/s)
DS-4 (139.264 Mb/s) SMPTE 259M (270/360 Mb/s)
STS-1 (51.84 Mb/s) SMPTE 292M (1.485 Gb/s)
STS-3/STM-1 (155.51 Mb/s)
Compliance with industry standards ANSI T1.102 and ITU-T G.703
Input VSWR (return loss), typical ≤1.1:1 (≥26.45 dB) to 4 GHz (see Figure 3)
nInput impedance 75 Ω±1.5% at DC and 25_C (derate at a linear rate to ±2% @ 0 and 50°C)
nOutput impedance 50 Ω±1.5% at DC and 25_C (derate at a linear rate to ±2% @ 0 and 50_C)
nAttenuation accuracy @ DC 2.46X ±1.5% at DC (--6 dB pwr)
Bandwidth, (--3dB) typical ≥4.0 GHz
Rise time, typical <100 ps (calculated from the formula .4/bandwidth = rise time)
Rated input voltage (Power)
Average power, DC
Peak power, AC
≤12 VDC or ≤12 VRMS (2Wmaximum@25_C) (derate at a linear rate to 1.625 W
@50 _C)
500 W (Duty cycle of 4% and maximum pulse width of 10 microseconds.)
Temperature
Operating
Nonoperating
Class 5 Limits
0_Cto+50_C(+32_F to +122 _F)
-- 5 5 _Cto+75_C(--67_F to +167 _F)
Humidity
Operating
Nonoperating
Class 5 Limits
+30 _Cto+50_C(+86_F to +122 _F), 90 to 95% RH
-- 5 5 _Cto+75_C(--67_F to +167 _F), 90 to 95% RH
EC Compliance This product is exempt from the requirements of the European 98/336 EEC directive.
Pollution Degree Pollution Degree 2 (as defined in IEC 61010-1). Note: Rated for indoor use only.
NOTE. If the ambient temperature changes by 5 °C or more, run the Probe
Calibration Routine described on page 11 to maintain the highest accuracy
measurements.

TCA75 Impedance Conversion Adapter
TCA75 Impedance Conversion Adapter Instructions 5
Frequency
10 MHz 1 GHz
-- 6 0
0.8
10 GHz100 MHz
-- 5 5
-- 5 0
-- 3 5
-- 2 5
-- 4 0
-- 4 5
-- 1 5
-- 5
0
-- 1 0
-- 2 0
-- 3 0
1.2
1.4
1.5
1.3
1.1
1.0
0.9
0.7
0.6
0.5
0.4
0.3
0
0.2
0.1
VSWR Return
loss, dB
Return
loss
VSWR
Figure 3: Typical VSWR and return loss

TCA75 Impedance Conversion Adapter
6TCA75 Impedance Conversion Adapter Instructions

TCA75 Impedance Conversion Adapter Instructions 7
Performance Verification
Use the following procedures to verify the warranted specifications of the
TCA75 adapter. Before beginning these procedures, photocopy the test record on
page 12, and use it to record the performance test results for your TCA75
adapter. The recommended calibration interval is one year.
These procedures are for use by qualified service personnel only.
Warm up the test equipment for at least 20 minutes prior to performing these
tests.
Test Equipment
Table 3 itemizes the equipment required, lists the minimum requirements, and
provides an example or part number of the equipment.
Table 3: Test equipment
Description Minimum requirements Example product
Power supply 1 VDC out across 75 Ωwith <0.5 mV
resolution
Wavetek 9100
Digital multimeter (2) 5 1/2 digit with sense, Ω4wire,
50 Ωand 75 Ω±0.1%,
DCV: 1 V and 200 mV ±0.1%
Keithley 2000 or Fluke 884X
SMA to BMA adapter Male SMA-to-female BMA Tyco 1059758-1
BNC banana adapter (3) BNC female-to-dual banana plug Tektronix part number 103-0090-00
50 ΩBNC cable (2) BNC male-to-BNC male, 24 inches Tektronix part number 012-1342-00
50 ΩBNC T adapter 2 female-to-1 male BNC Tektronix part number 103-0030-00
50 Ωtermination 50 Ω±0.1%, 2W, SMA Tektronix part number 015-1022-01
50 Ωtermination 50 Ω,2W,BNC Tektronix part number 011-0049-02
50 Ωadapter SMA barrel Tektronix part number 015-1012-00
50 Ωadapter SMA-to-BNC Tektronix part number 015-1018-00
75 ΩBNC cable (2) BNC male-to-BNC male, 24 inches Tektronix part number 012-1339-00
75 ΩBNC T adapter 2 female-to-1 male Pasternack PE9365
75 Ωtermination 75 Ω±0.025%, 2 VRMS,BNC Tektronix part number 011-0102-03

Performance Verification
8TCA75 Impedance Conversion Adapter Instructions
Output Impedance
This test checks the 50 Ωoutput impedance (of the TekConnect interface circuit)
of the adapter.
1. Set up the multimeter as follows:
Multimeter Setting
Mode Ω4 Wire
Range 100 Ω
2. Connect the TCA75 adapter as shown in Figure 4.
50.00 Ω
Multimeter
BNC to SMA adapter
SMA to BMA adapter
75 ΩTermination
SMA barrel
50 ΩBNC
cable
BNC to banana adapters
50 ΩT
adapter
TCA75 Adapter
50 ΩBNC
cable
Figure 4: Test setup for output impedance
3. Check that the multimeter reads 50 Ω±1.5% (49.25 Ωto 50.75 Ω).
4. Record the results in the test record.
5. Disconnect the setup.

Performance Verification
TCA75 Impedance Conversion Adapter Instructions 9
Input Impedance
This test checks the 75 Ωinput impedance of the adapter.
1. Connect the TCA75 adapter as shown in Figure 5.
75.00 Ω
Multimeter
75 ΩT
adapter
SMA barrel
SMA to BMA adapter
50 ΩTermination
(015-1022-01)
TCA75 Adapter
75 ΩBNC
cable
BNC to banana adapters
75 ΩBNC
cable
Figure 5: Test setup for input impedance
2. Check that the multimeter reads 75 Ω±1.5% (73.875 Ωto 76.125 Ω).
3. Record the results in the test record.
4. Disconnect the setup.

Performance Verification
10 TCA75 Impedance Conversion Adapter Instructions
Attenuation Accuracy
1. Set up the equipment as follows:
Multimeter #1 Setting
Mode DCV
Range 10 V (3 digit resolution)
Multimeter #2 Setting
Mode DCV
Range 1 V (3 digit resolution)
Power Supply Setting
DCV 1.000 V
2. Connect the equipment as shown in Figure 6.
SMAtoBMA
adapter
+--
Multimeter #1
Power supply
+1.000 V
75 ΩBNC cable
Multimeter #2
+.407 V
+1.000 V
50 ΩBNC cable
SMA barrel
SMA to BNC adapter
50 ΩTermination
(011-0049-02)
75 ΩT
adapter
TCA75 Adapter
BNC to banana
adapter
BNC to banana
adapter
75 ΩBNC
cable
BNC to banana
adapter
Figure 6: Measuring the attenuation accuracy
3. Power on the power supply, and adjust the output until multimeter #1 reads
1.000 V.
4. Check that the voltage is attenuated by 2.46X ±1.5% (multimeter #2 reads
0.402 V to 0.414 V).

Performance Verification
TCA75 Impedance Conversion Adapter Instructions 11
5. Record the measurement results in the test record.
6. Calculate the attenuation factor by dividing the voltage that you measured in
step 4 (the adapter output) into 1.000 V (the adapter input, from step 3).
7. Record the calculated results in the test record.
8. Power off the power supply, and disconnect the test setup.
Probe Calibration Routine
This is a functional check of the TCA75 adapter that uses the probe calibration
output signal and probe calibration feature of the oscilloscope.
1. Connect the TCA75 adapter to any channel on the oscilloscope.
2. Connect a 75 Ωcoaxial cable between the TCA75 adapter input and the
PROBE COMPENSATION output connector on the oscilloscope. The test
setup is now connected as shown in Figure 7.
TDS7404 Oscilloscope
75 ΩBNC cable
TCA75 Adapter
Probe
compensation
output
Figure 7: Probe setup
3. Select Probe Cal from the Vertical menu on the oscilloscope.
4. When the calibration routine completes, verify that the Pass message
displays. Record the results on the test record.
This completes the performance verification of the TCA75 adapter.

Performance Verification
12 TCA75 Impedance Conversion Adapter Instructions
TCA75 Test Record
Photocopy this page and use it to record the performance test results for your
TCA75 adapter.
TCA75 Test Record
Instrument Number:
Temperature: RH %:
Date of Verification: Technician:
TCA75 Performance Test Minimum Incoming Outgoing Maximum
Output impedance: 50 Ω±1.5% 49.25 __________ __________ 50.75
Input impedance: 75 Ω±1.5% 73.875 __________ __________ 76.125
Attenuation accuracy: 2.46 X (--6 dB) ±1.5%
(measured with 1.0 V on the input)
Input voltage
Output voltage
Input ÷output = attenuation factor
N/A
0.402
2.415
1.000
÷__________
= __________
1.000
÷__________
= __________
N/A
.414
2.487
Probe Calibration Routine Pass/Fail __________ __________ N/A