Agilent Technologies 8495D Service manual

Agilent Technologies
8495D/K Attenuators
Operating and Service
Manual
Agilent Part Number: 08495-90027
Printed in USA
Print Date: July 2002
Supersedes: April 2002

ii 8495D/K Attenuators Operating And Service Manual
Notice
The information contained in this document is subject to change without
notice.
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merchantability and fitness for a particular purpose. Agilent Technologies
shall not be liable for errors contained herein or for incidental or
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Agilent Technologies, Inc.
1400 Fountaingrove Parkway
Santa Rosa, CA 95403-1799, U.S.A.
© Copyright 2000–2002 Agilent Technologies, Inc.

8495D/K Attenuators Operating And Service Manual iii
What You’ll Find in This Manual…
•“Instrument Definition” on page 1
•“Description” on page 2
•“Specifications” on page 6
•“Installation” on page 8
•“Operating Instructions” on page 9
•“Operator’s Check” on page 10
•“Replaceable Parts” on page 12

iv 8495D/K Attenuators Operating And Service Manual
Warranty
Custom systems are warranted by contractual agreement between Agilent
Technologies and the customer.
Certification Agilent Technologies, Inc., certifies that this product met its published
specifications at the time of shipment from the factory. Agilent Technologies
further certifies that its calibration measurements are traceable to the
United States National Institute of Standards and Technology (NIST,
formerly NBS), to the extent allowed by the Institute’s calibration facility,
and to the calibration facilities of other International Standards
Organization members.
Documentation
Warranty THE MATERIAL CONTAINED IN THIS DOCUMENT IS
PROVIDED "AS IS," AND IS SUBJECT TO BEING CHANGED,
WITHOUT NOTICE, IN FUTURE EDITIONS. FURTHER, TO
THE MAXIMUM EXTENT PERMITTED BY APPLICABLE LAW,
AGILENT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS
OR IMPLIED WITH REGARD TO THIS MANUAL AND ANY
INFORMATION CONTAINED HEREIN, INCLUDING BUT NOT
LIMITED TO THE IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS FOR A PARTICULAR
PURPOSE. AGILENT SHALL NOT BE LIABLE FOR ERRORS
OR FOR INCIDENTAL OR CONSEQUENTIAL DAMAGES IN
CONNECTION WITH THE FURNISHING, USE, OR
PERFORMANCE OF THIS DOCUMENT OR ANY
INFORMATION CONTAINED HEREIN. SHOULD AGILENT
AND THE USER HAVE A SEPARATE WRITTEN AGREEMENT
WITH WARRANTY TERMS COVERING THE MATERIAL IN
THIS DOCUMENT THAT CONFLICT WITH THESE TERMS,
THE WARRANTY TERMS IN THE SEPARATE AGREEMENT
WILL CONTROL.
Assistance Product maintenance agreements and other customer assistance agreements
are available for Agilent Technologies products.
For assistance, call your local Agilent Technologies Sales and Service Office
(refer to “Service and Support” on page v).

8495D/K Attenuators Operating And Service Manual v
Service and Support
Any adjustment, maintenance, or repair of this product must be performed
by qualified personnel. Contact your customer engineer through your local
Agilent Technologies Service Center. You can find a list of local service
representatives on the Web at:
http://www.agilent.com/find/assist
Click on “Contact Us” and select your country.
If you do not have access to the Internet, one of these centers can direct you
to your nearest Agilent Technologies representative.
United States [phone]
Canada [phone]
Europe (41 22) 780.6111 (Switzerland)
(33 1) 69 82 66 66 (France)
(49 7031) 464-6222 (Germany)
(44 188) 9696622 (Great Britain)
Japan 0120-32-0119
Latin America (11) 7297-3700 (Brazil)
Australia/New
Zealand 1-800-802-540 (Australia) 0800-738-378 (New Zealand)
Asia-Pacific 080-047-669

vi 8495D/K Attenuators Operating And Service Manual
Safety and Regulatory Information
Review this product and related documentation to familiarize yourself with
safety markings and instructions before you operate the instrument. This
product has been designed and tested in accordance with international
standards.
WARNING The WARNING notice denotes a hazard. It calls attention to a procedure,
practice, or the like, that, if not correctly performed or adhered to, could result
in personal injury. Do not proceed beyond a WARNING notice until the
indicated conditions are fully understood and met.
CAUTION The CAUTION notice denotes a hazard. It calls attention to an operating
procedure, practice, or the like, which, if not correctly performed or adhered
to, could result in damage to the product or loss of important data. Do not
proceed beyond a CAUTION notice until the indicated conditions are fully
understood and met.
Instrument Markings
When you see this symbol on your instrument, you should refer to the instrument’s
instruction manual for important information.
This symbol indicates hazardous voltages.
The laser radiation symbol is marked on products that have a laser output.
This symbol indicates that the instrument requires alternating current (ac) input.
The CE mark is a registered trademark of the European Community. If it is
accompanied by a year, it indicates the year the design was proven.
The CSA mark is a registered trademark of the Canadian Standards Association.
1SM1-A This text indicates that the instrument is an Industrial Scientific and Medical Group 1
Class A product (CISPER 11, Clause 4).
!

8495D/K Attenuators Operating And Service Manual vii
Safety Earth
Ground This is a Safety Class I product (provided with a protective earthing
terminal). An uninterruptible safety earth ground must be provided from the
main power source to the product input wiring terminals, power cord, or
supplied power cord set. Whenever it is likely that the protection has been
impaired, the product must be made inoperative and secured against any
unintended operation.
Before Applying Power Verify that the product is configured to match the available main power
source as described in the input power configuration instructions in this
manual. If this product is to be powered by autotransformer, make sure the
common terminal is connected to the neutral (grounded) side of the ac power
supply.
This ISM device complies with Canadian ICES-001.
Cet appareil ISM est conforme a la norme NMB du Canada.
This symbol indicates that the power line switch is ON.
This symbol indicates that the power line switch is OFF or in STANDBY position.

viii 8495D/K Attenuators Operating And Service Manual

8495D/K Attenuators Operating And Service Manual 1
Instrument Definition
This manual contains installation, operation, and test information for the
8495D and 8495K.
Instruments Covered by
Manual The instruments covered by this manual have a two-part serial number. The
first four digits and letter comprise the serial number prefix. The last five
digits form the sequential suffix that is unique to each instrument. The
contents of this manual apply to instruments with the following serial
prefixes:
An attenuator manufactured after the printing of this manual may have a
serial prefix that is not listed above. This unlisted serial prefix indicates that
the attenuator is different from those documented in this manual.
8495D: 1711A 2406A 2508A 2544A 2852A 3308A
8495K: 1711A 2406A 2508A 2544A 2808A

28495D/K Attenuators Operating And Service Manual
Description
Description
The Agilent 8495D and 8495K are 50-ohm, dc to 26.5 GHz, 0-70 dB (in
10 dB steps), coaxial attenuators with APC 3.5 connectors. Each attenuator
is made up of four attenuation sections connected in cascade. Each section
consists of a precision thin-film attenuator card, a lossless thru-line, and a
ganged pair of edge line transmission lines. The edge lines are flexed to
make contact with either the attenuator card or the thru-line. The edge line
contacts are gold-plated leaf springs which ensure long life and high
repeatability. In the 8495D, the edge line controls are flexed by low-torque
cams. In the 8495K, the edge line controls are flexed by solenoid plungers
(see Figure 1).
Table 1 on page 3 shows the switching arrangement required to increase the
amount of attenuation from 0 to 70 dB in 10 dB steps. In the 8495K, to
ensure specified performance, it is recommended that the attenuator sections
shown in the table below be used. Also, when changing attenuation, it is
good practice to insert the required sections before deletion of the unneeded
sections. With the attenuator set for 0 dB attenuation, only the insertion loss
(residual attenuation) remains.
Figure 1 8495K Programmable Four-Section Attenuator Schematic Diagram

8495D/K Attenuators Operating And Service Manual 3
Description
In the 8495K, each solenoid requires a drive of 20 to 30 V. The switching
current is approximately 125 mA at 24 Vdc per section for the 8495K. The
solenoid switching time is less than 20 milliseconds including settling time.
Once switched, the solenoid plungers are held in place by permanent
magnets and the solenoid plungers automatically disconnect the selected coil
drive and connect the opposite coil drive (see Figure 1 on page 2 and
Figure 3 on page 5).
Table 1 Attenuator Switching
* D model only
** K model only
CAUTION Do not exceed the RF power rating of 1 W average or 100 W peak with a
maximum pulse width of 10 µs. Do not connect an attenuator RF input or
output connector to greater the 7Vdc. If the attenuator must be connected to
a device with a potential greater than 7 Vdc, use a blocking capacitor.
Supplied Accessories A solenoid drive cable is supplied with the 8495K. The cable is 1.5 m (5 ft)
long with a mating connector plug on one end and the other end is
unterminated (see Figure 2 on page 4). The part number for this cable is
8120-2178, and is available as a spare or replacement. The cable connector
plug and contacts are available from Viking Industries Inc. The part number
is TKP12-100-P-TS-100-AU. The connector plug and contacts without the
cable can be ordered from a Viking distributor. Information on replaceable
parts is available in Table 3 on page 5.
Solenoid Cable
Connectors Refer also to Figure 2 on page 4.
Attenuator Sections
Attenuation
(dB) 1 10 dB 2 20 dB 3 20 dB 4 20 dB
10 X
20 X* X**
30 X X* X**
40 X X
50 X X X
60 XXX
70 XXXX

48495D/K Attenuators Operating And Service Manual
Description
Figure 2 Solenoid Cable Pin Configuration
Table 2 Solenoid Cable Connectors
Section Section 1 Section 2 Section 3 Section 4 Power
Solenoid Coil Thru-Line Atten
Card Thru-Line Atten Card Thru-Line Atten Card Thru-Line Atten Card V+
Cable Wire
Color Code1
1. Five-foot cable and mating plug assembly provided.
VIO YEL BLK GRN ORG BLU BRN WHT RED
Connector
Plug Pin
Number 2
2. Pin 1 (red wire) is common for all coils. Pins 2, 3 and 4 are not used.
567891011121
8495K 0 dB 10 dB 0 dB 20 dB 0 dB 20 dB 0 dB 20 dB –
Option 016
Flat Pack
Plug Pin
Number3
3. Pin 6 is common for all coils. Pins 1, 7, 8, 12, and 14 are not used.
13 2 11 5 3 9 4 10 6

8495D/K Attenuators Operating And Service Manual 5
Description
Figure 3 Typical Solenoid Coil Driver Circuit
Table 3 Solenoid Cable Replaceable Parts
Part Number Description
2220-0006 Screw, fillister Head 4-40x7/8 in. (for attaching base)
8120-2178 Cable, solenoid drive, 1.5 meters (5 feet) long, connector plug
on one end and other end unterminated (8495K)
0370-1091 Knob (84950)
08496-20008 Base
TKP12-100-P-TS-100-AU 1Connector Plug and Contacts only without cable (8495K)
1. Available from Viking Industries, Inc., Chatsworth, California 91311.

68495D/K Attenuators Operating And Service Manual
Specifications
Specifications
Frequency Range
and Attenuation
Attenuation Accuracy
Maximum Insertion Loss (0.4 + 0.9f) dB
where “f” is the frequency in GHz
Attenuation Repeatability 0.01 dB, dc to 18.0 GHz
0.05 dB, 18.0 to 26.5 GHz
RF Power Handling
Capability 1 W average, 100 W peak with maximum pulse width of 10 microseconds
Solenoid Drive For Agilent 8495K only.
Switching speed Maximum 20 milliseconds including settling time
Frequency Range dc to 26.5 GHz
Attenuation 0 to 70 dB in 10 dB steps
Attenuation Accuracy ( dB, referenced from 0 dB)
Attenuation
Selection (dB) dc–6.0 GHz 6.0–12.4 GHz 12.4–18.0 GHz 18.0–26.5 GHz
10 0.3 0.4 0.5 0.7
20 0.5 0.5 0.6 0.8
30 0.6 0.7 0.8 1.0
40 0.7 0.9 1.1 1.5
50 0.8 1.0 1.2 1.6
60 1.0 1.3 1.4 1.9
70 1.1 1.5 1.7 2.3
Solenoids Drive Coil Voltage Switching Current
8495K 20 to 30 Vdc 125 mA at 24V (approx.)

8495D/K Attenuators Operating And Service Manual 7
Specifications
Maximum SWR
Physical Characteristics
Minimum Life >5 million cycles per section
Environment Limits The attenuator should be stored in a clean, dry environment. The storage and
operating environments of the instruments should be within the following
limits.
NOTE Containers and materials identical to those used in factory packaging are
available through Agilent Technologies offices. If the instrument is being
returned to Agilent Technologies for servicing, attach a tag indicating the
type of service required, return address, model number, and full serial
number. Also, mark the container FRAGILE to assure careful handling. In
any correspondence, refer to the instrument by model number and full serial
number.
Instrument Frequency Range (GHz) Maximum SWR
8495D, 8495K dc to 6.0
6.0 to 12.4
12.4 to 18
18 to 26.5
1.25
1.45
1.9
2.2
Instrument Dimensions 1
(depth x width x height) Weight
8495D 6.25 in x 2.0625 in x 1.6875 in
159 mm x 52 mm x 43 mm 15 oz
425 g
8495K 5.625 in x 2.0625 in x 1.6875 in
159 mm x 52 mm x 43 mm 16 oz
454g
1. Dimensions are in millimeters and inches. Dimensions are for general information only. If
dimensions are required for building special enclosures, contact your Agilent field engineer.
Characteristic Storage Value Operating Value
Temperature –40 to +75 °C 0 to 55 °C
Humidity < 95% relative < 95% relative
Altitude < 7600 m (25000 ft) < 4600 m (15000 ft)

88495D/K Attenuators Operating And Service Manual
Installation
Installation
Initial Inspection Inspect the shipping container for damage. If the shipping container or
cushioning material is damaged, it should be kept until the contents of the
shipment have been checked for completeness and the instrument has been
checked mechanically and electrically. A procedure for checking electrical
performance is given under “Operator’s Check” on page 10 (also see
“Performance Tests” on page 11). If the contents of the shipment are
incomplete, if there is mechanical damage or defect, or if the instrument
does not pass the electrical performance test, notify the nearest Agilent
Technologies office. If the shipping container is damaged, or the cushioning
material shows signs of stress, notify the carrier as well as the Agilent
Technologies office. Keep the shipping materials for the carrier's inspection.
The Agilent office will arrange for repair or replacement without waiting for
claim settlement.
Mating Connectors The APC 3.5 connector is a 3.5-mm air line connector that will mate with
the SMA type connectors. The SWR performance of this hybrid connection
is similar to a mated pair of SMA connectors when used within the
frequency range of the SMA connector.
Option The attenuators are configured with the APC 3.5 female connectors and are
designated as Option 004.
CAUTION When installing the instrument, make sure that the connectors do not support
weight or bear torque. The preferred procedure is to set up all equipment in
position before connecting the instrument. Either connector may be used as
the input or output connector.
Installation
Instructions The 8495K solenoid drive cable connector plug is connected by aligning the
plug (P1) with the jack (J1) on the attenuator, and then pushing the plug over
the jack. The plug is removed by grasping the ribbed sides of the plug and
squeezing them together while pulling back until the plug clears the jack.

8495D/K Attenuators Operating And Service Manual 9
Operating Instructions
Operating Instructions
CAUTION Do not apply power greater than 1 W average, or 100 W peak with a
maximum pulse width of 10 microseconds. If these limits are exceeded, the
attenuators may be damaged.
CAUTION For the 8495K, do not ground both solenoid drive pins of the programmable
attenuator at the same time. This causes rapid cycling of the solenoid and
could reduce the operating life of the attenuator. The rapid cycling may
produce a buzzing sound from the attenuator.
Operating Information Either RF connector may be used as the input or output connector. Connect
the solenoid drive cable of the programmable attenuator to the solenoid drive
connector (Jl). By applying the proper voltage and grounds to the proper
pins of Jl, the attenuator will either increase or decrease the amount of
attenuation as selected.

10 8495D/K Attenuators Operating And Service Manual
Operator’s Check
Operator’s Check
The Operator's Check is supplied to allow the operator to make a quick
check of the instrument prior to use or if a failure is suspected.
Description The attenuator is driven from a 50-ohm signal source at 1 kHz. The output
level from the attenuator is detected by a narrow-bandwidth voltmeter. The
attenuator and detector range switches are stepped together and the
variations in level noted. This verifies that each attenuator section is being
properly switched and checks the low-frequency accuracy of the attenuator.
NOTE The SWR meter used in this check is calibrated for a square-law detector
and therefore the range changes and errors (read in dB) are twice that
indicated by the meter.
Figure 4 Operator’s Check Setup
Procedure 1. Connect equipment as shown in Figure 4 with the attenuator set to 0 dB.
2. Set the test oscillator to 0.3 Vrms at 1 kHz.
3. Set SWR meter range to 2 dB (expanded) and adjust its bandwidth to
center of adjustment range. Fine tune oscillator frequency to obtain
maximum meter indication.
4. Set attenuator and SWR meter range switch as shown in Table 4 and
verify that SWR meter indicates within the limits shown.

8495D/K Attenuators Operating And Service Manual 11
Operator’s Check
Performance Tests The attenuator can be tested to the accuracy of the Specifications on page 6
with an automatic network analyzer or equivalent equipment of suitable
accuracy. If an automatic network analyzer is available, test the attenuator
using the procedures in the analyzer's operating manual.
Refer to the Agilent 11713A Attenuator/Switch Driver Operating and
Service Manual for programming instructions.
NOTE The attenuators have no internal adjustments and should not be opened. If
defective, return the attenuator to the nearest Agilent Technologies office for
repair.
Table 4 Attenuator and SWR Settings
SWR Meter
Range (dB) Attenuation Meter Indication (dB)
8495D/K Minimum Actual Maximum
2 0 Set to 0.5
6 10 1.20 1.80
12 20 0.15 0.85
16 30 1.05 1.95
221
1. Adjust range by 2 dB, if needed, to obtain a on-scale indication.
40 –0.40 1.40
26150 0.50 2.50
32160 –0.60 1.60
36170 0.35 2.65

12 8495D/K Attenuators Operating And Service Manual
Replaceable Parts
Replaceable Parts
Table 5 lists the replaceable parts which are the only parts that can be
replaced without access to the interior of the instrument. If any parts not
listed below need replacement, return the instrument to Agilent
Technologies.
CAUTION Due to special fixtures necessary for assembly, do NOT attempt to replace
any parts not listed in the table below. If the instrument is opened, the
warranty is void.
Troubleshooting Troubleshooting consists of performing the “Operator’s Check” on page 10.
If the instrument does not perform within limits, return the instrument to
Agilent Technologies.
Table 5 Replaceable Parts
Description Part Number
Knob (8495D) 0370-1091
Cable, solenoid drive, 1.5 m (5 ft) long, connector plug on one
end and other end un-terminated (8495K) 8120-2178
Screws for both bases: 4-40 x 7/8 in. Fillister head 2220-0006
Base 5041-3888
Connector plug and contacts only without cable (8495K) *TKP12-100-P-TS-100-AU
*Available from distributors of Viking Industries, Inc., Chatsworth CA 91311