Agilent Technologies 54701A Manual

User and Service Guide
Publication number 54701-97003
September 2002
For Safety and Regulatory information see the pages behind the index.
© Copyright Agilent Technologies 1992-2002
All Rights Reserved
Agilent Technologies 54701A
2.5-GHz Active robe

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Agilent Technologies 54701A 2.5-GHz Active
robe
The Agilent Technologies 54701A 2.5-GHz Active Probe is a probe solution for
high-frequency applications.This probe is designed to be powered from a
connector at the front of the oscilloscope or with the 1143A Probe Offset
Control and Power Module. It can be used with any measuring instrument
with a 50-Ω input. Following are the main features. See Chapter 3 for full
specifications and characteristics.
• A bandwidth of 2.5 GHz
• Input resistance of 100 kΩ
• Input capacitance of approximately 0.6 pF
• Dynamic range of ±5 V peak ac and ±50 Vdc
• Variable dc offset of ±50 V
• Excellent immunity to ESD and over-voltages
Accessories Supplied
The following accessories are supplied. See “Using probe accessories” in
chapter 1 for a complete list.
• Type N(f) to BNC(m) adapter
• “Walking-stick” ground
• Box of small accessories
• Carrying case
• User and Service Guide
Accessories Available
The following accessories can be ordered.
• Type N(m) to probe tip adapter and 50-Ω termination 11880A
• BNC(m) to probe tip adapter 10218A
• Type N(f) to APC 3.5(f) bulkhead adapter 5081-7722 (For use with the
54120 family. Order with the probe as Option 001.)

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Options Available
The following options are available.
• Option 001 Type N(f) to APC 3.5(f) bulkhead adapter (To use the probe
with 54120 family)
• Option 0B1 Additional User and Service Guide
Service Strategy
Except for the probe tip there are no field replacable parts in the Active
Probe. Depending on the warranty status of your probe if it fails it will be
replaced or exchanged. See chapter 3 “Service ” for further information and
how to return your probe to Agilent Technologies for service.
Option 001

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In This Book
This book provides use and service documentation for the 54701A 2.5-GHz
Active Probe. It is divided into three chapters.
Chapter 1 shows you how to set up and operate the probe using the power
connector on the oscilloscope or the separately available 1143A Probe Offset
Control and Power Module.
Chapter 2 gives you information about some important aspects of probing and
how to get the best results with your probe.
Chapter 3 provides service information. Included is how to test the probes
performance how and when to make the one adjustment and how to
determine if your probe needs repair.

Contents
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In This Book 4
1 Operating the Probe
To inspect the probe 9
To connect the probe 12
Connecting the probe to the 54120 family oscilloscopes 13
Using the probe with oscilloscope power 14
Using the probe with the 1143A power module 15
Using probe accessories 16
Additional Accessories 20
2 Probing Considerations
Capacitive Loading Effects 25
Ground Inductance Effects 27
Probe Bandwidth 31
Conclusion 32

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Contents
3Service
Specifications 35
Characteristics 36
General Characteristics 37
Recommended Test Equipment 38
Service Strategy 39
To clean the instrument 40
To return the probe to for service 40
To test input resistance 42
To test dc gain accuracy 43
To test bandwidth 45
To adjust offset zero 49
Failure Symptoms 51
To prepare the probe for exchange 53
Replaceable Parts 54
Theory of Operation 56

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1
Operating the robe

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Chapter 1: Operating the Probe
Figure 1
54710A Active Probe
11880A Type-N(m) to
Probe Adapter
(not supplied order
separately)
5081-7722A Type-N(m)
to APC 3.5(f) Adapter
(supplied as Option 001
or order separately)
Walking-stick Ground
(supplied)
N(f) to BNC(m) Adapter
(supplied)
Included with the probe is a
box of small accessories. See
Page 16 for a complete list of
accessories.

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Chapter 1: Operating the Probe
Introduction
This chapter shows you how to connect and operate the 54701A Active Probe.
The following information is covered in this chapter:
• Inspection
• Probe operating range
• Connecting the probe
• Operating the probe with oscilloscope power
• Operating the probe with a power module
• Using accessories
To inspect the probe
❏Inspect the shipping container for damage.
Keep a damaged shipping container or cushioning material until the
contents of the shipment have been checked for completeness and the
instrument has been checked mechanically and electrically.
❏Check the accessories.
Accessories supplied with the instrument are listed in "Accessories
Supplied" in table 1 page 16 in this manual.
• If the contents are incomplete or damaged notify your Agilent
Technologies sales office.
❏Inspect the instrument.
• If there is mechanical damage or defect or if the instrument does not
operate properly or pass calibration tests notify your Agilent
Technologies sales office.
• If the shipping container is damaged or the cushioning materials show
signs of stress notify the carrier as well as your Agilent Technologies
sales office. Keep the shipping materials for the carrier's inspection.
The Agilent office will arrange for repair or replacement at Agilent
Technologies’ option without waiting for claim settlement.

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Chapter 1: Operating the Probe
Probe Operating Range
robe Operating Range
Figure 2 shows the maximum input voltage for the active probe as a function
of frequency. This is the maximum input voltage that can be applied without
risking damage to the probe.
Figure 2
Maximum Input Voltage vs Frequency
Figure 3 shows the operating range of the probe. For the most accurate
measurements and safety for the probe signals should be within the indicated
operating region.
Figure 3
Probe Operating Range
Area of Optimum
Operating