For warranty service or repair, this product must be returned to a service facility designated by HP. Buyer shall prepay shipping charges to HP and HP shall pay shipping charges, duties, and taxes for products returned to HP from another country.
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MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. Exclusive Remedies THE REMEDIES PROVIDED HEREIN ARE BUYER’S SOLE AND EXCLUSIVE REMEDIES. HP SHALL NOT BE LIABLE FOR ANY DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, WHETHER BASED ON CONTRACT, TORT, OR ANY OTHER LEGAL THEORY.
For continued protection against fire hazard, replace the line fuse(s) only with fuses of the same type and rating (for example, normal blow, time delay, etc.). The use of other fuses or material is prohibited. HP EPM-441A/442A Service Guide...
This terminal is for use where the earthing cannot be assured. At least an 18AWG earthing conductor should be used in such an instance, to ground the instrument to an assured earth terminal. HP EPM-441A/442A Service Guide...
Equipment for Measurement, Control and Laboratory Use and has been supplied in a safe condition. The instruction documentation contains information and warnings which must be followed by the user to ensure safe operation and to maintain the instrument in a safe condition. HP EPM-441A/442A Service Guide...
List of Related Publications List of Related Publications The HP EPM-441A and HP EPM-442A User’s Guides are also available in the following languages: • English Language User’s Guide - Standard • German Language User’s Guide - Option ABD • Spanish Language User’s Guide - Option ABE •...
Thailand: (66-2) 661 3900 For countries in Asia Pacific not listed contact: Hewlett-Packard Asia Pacific Ltd. 17-21/F Shell Tower, Times Square, 1 Matheson Street, Causeway Bay, Hong Kong tel: (852) 2599 7070 fax: (852) 2506 9285 HP EPM-441A/442A Service Guide...
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Hewlett-Packard Canada Ltd. 5150 Spectrum Way Mississauga, Ontario L4W 5G1 (905) 206 4725 In Europe, Africa and Middle East please call your local HP sales office or representative: Austria: (1) 25000-0 Belgium and Luxembourg: (02) 778 3417 Baltic Countries: (358) 08872 2100...
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In any correspondence or telephone conversations, refer to the power meter by its model number (which is on the front panel) and full serial number (which is on the rear panel). With this information, the HP representative can quickly determine whether your unit is still within its warranty period.
4. Seal the shipping container securely with strong nylon adhesive tape. 5. Mark the shipping container “FRAGILE, HANDLE WITH CARE” to ensure careful handling. 6. Retain copies of all shipping papers. HP EPM-441A/442A Service Guide...
This chapter describes how each of the power meter’s individual assemblies operate. Chapter 5: Replaceable Parts This chapter details the power meter’s replaceable parts. It also explains how to assemble and disassemble the power meter. HP EPM-441A/442A Service Guide xiii...
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About this Guide HP EPM-441A/442A Service Guide...
Environmental Characteristics ............ 1-14 General Conditions..............1-14 Operating Environment ............1-14 Storage Conditions ..............1-14 General ..................1-15 Dimensions ................1-15 Weight ..................1-15 Safety ..................1-15 Remote Programming ............1-15 Non-Volatile Memory ............. 1-16 HP EPM-441A/442A Service Guide Contents-1...
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Power Reference Level Test ............2-10 Description................2-10 Equipment ................2-11 Test Setup ................2-11 Procedure ................2-11 HP E-Series Power Sensor Interface Test ........2-14 Procedure ................2-14 HP E-Series Power Sensor Functional Test ........ 2-15 Description................2-15 Equipment ................2-15 Procedure ................
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Replacing the Front Panel Power Reference Cable Assembly ................. 5-17 Replacing the Rear Panel Power Sensor Cable Assemblies (Options 002 and 003)......... 5-18 Replacing the Rear Panel Power Reference Cable Assembly (Option 003) ............5-20 HP EPM-441A/442A Service Guide Contents-3...
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Contents-4 HP EPM-441A/442A Service Guide...
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Power Reference Level Test Setup ........... 2-11 Sensor Functional Test Setup ........... 2-16 Sensor Functional Test Setup with Attenuator ....... 2-17 Adjustment Setup ..............3-4 A2L9 Adjustment Location ............3-5 Adjustment Setup ..............3-6 A2R90 Adjustment Location ............. 3-10 HP EPM-441A/442A Service Guide Contents-5...
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Contents-6 HP EPM-441A/442A Service Guide...
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Required Equipment ..............2-3 Zero Test Results ............... 2-6 Instrument Accuracy Results............ 2-9 Power Reference Level Result........... 2-13 Functional Test Result .............. 2-17 Performance Test Record ............2-18 Post Repair Adjustments, Tests, and Checks ......3-3 HP EPM-441A/442A Service Guide Contents-7...
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Contents-8 HP EPM-441A/442A Service Guide...
These characteristics are shown in italics or denoted as “typical”, “nominal” or “approximate”. For information on measurement uncertainty calculations, refer to HP Application Note 64-1A, “Fundamentals of RF and Microwave Power Measurements”, Literature Number 5965-6630. HP EPM-441A/442A Service Guide...
Power Range -70 dBm to +44 dBm (100 pW to 25 W), power sensor dependent Power Sensors Compatible with all HP 8480 series power sensors and HP ECP-series power sensors. Single Sensor Dynamic Range 90 dB maximum (HP ECP-series power sensors)
Zero Set (digital settability of zero): Power sensor dependent (refer to Table 1-1). For HP ECP-series power sensors, this specification applies when zeroing is performed with the sensor input disconnected from the POWER REF.
Power Meter Specifications Power Reference Power Output 1.00 mW (0.0 dBm). Factory set to ± 0.7% traceable to the US National Institute of Standards and Technology. Accuracy ± 1.2% worst case ( ± 0.9% rss) for one year. HP EPM-441A/442A Service Guide...
50 MHz nominal 1.05 maximum Connector Type N (f), 50 Ω Measurement Speed Over the HP-IB, three measurement speed modes are available as shown, along with the typical maximum measurement speed for each mode: • Normal: 20 readings/second • x2: 40 readings/second •...
Multiplier” for the appropriate mode (normal or x2) and number of averages to determine the total measurement noise value. For example, for an HP 8481D power sensor in normal mode with the number of averages set to 4, the measurement noise is equal to: (<45 pW x 2.75) = <124 pW...
2. The number of averages at 16 (for normal mode) and 32 (for x2 mode), at a constant temperature, measured over a 1 minute interval and 2 standard deviations. For HP ECP-series power sensors the measurement noise is measured within the low range. Refer to the relevant power sensor manual for further information.
Specifications Power Meter Supplemental Characteristics Settling Time 0 to 99% settled readings over the HP-IB. For HP 8480 series power sensors Manual filter, 10 dB decreasing power step: Table 1-4: Settling Time Number of 1024 Averages Settling Time (s) 0.15...
When a decreasing power step crosses the power sensor’s auto-range switch point, add 25 ms. Refer to the relevant power sensor manual for further information. For HP ECP-series power sensors in normal and x2 speed modes, manual filter, 10 dB decreasing power step: Table 1-5: Settling Time...
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Settling Dynamic Dynamic Times Times Range Range 120 ms 70 ms 10 dB 10 dB 400 ms 210 ms 10 dB 10 dB 6.5 s 3.4 s 10 dB 10 dB Minimum dBm Minimum dBm HP EPM-441A/442A Service Guide 1-11...
This parameter is also known as short term stability and is specified as the change in the power meter indication over a short time interval (usually one minute) for a constant input power at a constant temperature. 1-12 HP EPM-441A/442A Service Guide...
Binding post, accepts 4 mm plug or bare-wire connection Line Power • Input Voltage Range: 85 to 264 Vac, automatic selection • Input Frequency Range: 47 to 63 Hz • Power Requirement: approximately 50 VA (14 Watts) HP EPM-441A/442A Service Guide 1-13...
15% at 40ºC (non-condensing) Maximum Altitude 3,000 meters (9,840 feet) Location For use indoors. Storage Conditions Storage Temperature -20ºC to +70ºC Non-Operating Maximum Humidity 90% at 65ºC (non-condensing) Non-Operating Maximum Altitude 15,240 meters (50,000 feet) 1-14 HP EPM-441A/442A Service Guide...
1010-1:1993 • EN60825-1: 1994/IEC 825-1: 1993 Class 1 • Low Voltage Directive 72/23/EEC Remote Programming Interface HP-IB interface operates to IEEE 488.2. Command Language SCPI standard interface commands. HP EPM-441A is HP 437B code compatible. HP EPM-441A/442A Service Guide 1-15...
The line voltage for the power meter must be 85 to 264 Vac and the line frequency must be 47 to 63 Hz. c. The ambient temperature must be 0 to 55 HP EPM-441A/442A Service Guide...
Option H75 HP 478A Option H76 Power Sensor HP E-series power sensor 30 dB Attenuator HP 11807A HP 8491A Option 030 Power Sensor Cable HP 11730A P and A 1. P = Performance Tests, A = Adjustments HP EPM-441A/442A Service Guide...
Equipment settings, other than those for the power meter, are stated in general terms. It is assumed that the person will select the proper cables, adapters, and probes required for test setups illustrated in this chapter. HP EPM-441A/442A Service Guide...
This test also takes drift and noise into account, since drift, noise and zero readings cannot be separated. Equipment Range Calibrator ........HP 11683A Power Sensor Cable ......HP 11730A Test Setup Power Meter Range Calibrator...
The following procedure should be performed for the Zero Test. Note The procedure details the key presses required on the HP EPM-441A. For the HP EPM-442A the equivalent key presses should be performed on both channels. 1. Connect the equipment as shown in Figure 2-1.
Description The power meter accuracy is verified for various power inputs. The range calibrator is switched to provide these reference inputs. Equipment Range Calibrator ........HP 11683A Power Sensor Cable ......HP 11730A Test Setup Power Meter Range Calibrator CHANNEL A...
Test. Note The procedure details the key presses required on the HP EPM-441A. For the HP EPM-442A the equivalent key presses should be performed on both channels. 1. Connect the equipment as shown in Figure 2-2. 2. Switch the power meter on.
3.156 mW, 10.03 mW, 31.78 mW, and 101.3 mW respectively. It is not necessary to check instrument accuracy in dBm. The Note power meter uses the same internal circuitry to measure power and mathematically converts watts to dBm. HP EPM-441A/442A Service Guide...
Hewlett-Packard test instruments of known capability. If equivalent test instruments are used, signal acquisition criteria may vary and reference should be made to the manufacturer’s guidelines for operating the instruments. 2-10 HP EPM-441A/442A Service Guide...
• R is the resistance of the mount resistor in the HP 432A power meter. • Calibration Factor is the value of the thermistor mount at 50 MHz. HP EPM-441A/442A Service Guide...
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5. Set the HP 432A RANGE switch to Coarse Zero. Adjust the front panel Course Zero control to obtain a zero meter indication. 6. Fine zero the HP 432A on the most sensitive range, then set the RANGE switch to 1 mW.
V ___________ 12. Disconnect the DVM negative input lead from the V connector on the HP 432A. Reconnect it to the HP 432A chassis ground. 13. Observe the DVM reading. Record the reading as V comp __________ comp 14.
HP E-Series Power Sensor Interface Test HP E-Series Power Sensor Interface Test The HP E-series power sensors have their sensor calibration tables stored in EEPROM which enables the frequency and calibration factor data to be downloaded automatically by the power meter. The frequency and calibration factor data have checksums which are compared with the data downloaded by the power meter.
This test verifies that the meter/sensor combination can make RF measurements. The HP E-series power sensors operate over a 90 dB dynamic range (-70 to +20 dBm). However, since there is an amplifier in these power sensors, the voltages presented to the power sensor connector are always within the range of voltages available from the HP 11683A range calibrator.
To complete the Functional Test the following procedure should be performed. Note The procedure details the key presses required on the HP EPM-441A. For the HP EPM-442A the equivalent key presses should be performed on both channels. 1. Connect the equipment as shown in Figure 2-4. Power Meter...
Performance Tests HP E-Series Power Sensor Functional Test 6. Connect the 30 dB attenuator as shown in Figure 2-5. Power Meter HP E-Series Power Sensor HP 11708A 30 dB ATTENUATOR CHANNEL A HP 11730A Figure 2-5: Sensor Functional Test Setup with Attenuator System 7.
Performance Tests Performance Test Record Performance Test Record Model HP EPM-441A/442A Power Meter Tested by ___________________________________________ Serial Number _______________________________________ Date _______________ Table 2-6: Performance Test Record Channel A Channel B Test Min Result Actual Actual Result Result Result − 76.40 nW + 76.40 nW...
Maintenance should be performed only by trained personnel who are aware of the hazards involved. When the maintenance procedure can be performed without power, the power should be removed. HP EPM-441A/442A Service Guide...
A5 Daughter Assembly Instrument Accuracy Test A6 Measurement Assembly Zero Test, Instrument Accuracy Test W1 or W2 Power Sensor Instrument Accuracy Test, Zero Test Cable BT1 Battery Battery Self Test Power Reference Cable Kits Power Reference Level Test HP EPM-441A/442A Service Guide...
Frequency Counter POWER Figure 3-1: Adjustment Setup Equipment Frequency Counter........ HP 5314A Procedure 1. Ensure that the power meter has been powered on for at least 30 minutes before making any measurements. 2. Connect the equipment as shown in Figure 3-1. Set up the counter to measure frequency.
Adjustments Power Reference Oscillator Frequency Adjustment 3. Turn the power reference on by pressing Zero on the HP EPM-441A. Power Ref Off On Zero on the More Power Ref Off On HP EPM-442A. 4. Observe the reading on the frequency counter. If it is 50.0 ±...
If equivalent instruments are used, signal acquisition criteria may vary and reference should be made to the manufacturer’s guidelines for operating the equipment. The power meter may be returned to the nearest HP office to have Note the power reference oscillator checked and/or adjusted.
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• R is the resistance of the mount resistor in the HP 432A power meter. • Calibration Factor is the value of the thermistor mount at 50 MHz. HP EPM-441A/442A Service Guide...
HP 432A have been powered on for at least 30 minutes before proceeding to the next step. 4. Set the HP 432A range switch to coarse zero and adjust the front panel coarse zero control to obtain a zero meter indication.
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8. Observe the reading on the DVM. If less than 400 µ V, proceed with the next step. If 400 µ V or greater, press and hold the HP 432A fine zero switch and adjust the coarse zero control so that the DVM indicates 200 µ...
12. Reconnect the negative lead to the V connector on the rear panel of the HP 432A. The DVM is now set up to measure V which represents the power reference oscillator output level. 13. Calculate the required value of V using equation 2.
R. Other uncertainties comp which should be included are: Maths Assumptions: ± 0.01% • Effective Efficiency Calibration: ± 0.05% • Mismatch Uncertainty with Source and Mount: ± 0.1% • SWR: ≤1.05 • These values are typical. HP EPM-441A/442A Service Guide 3-11...
Display increase the contrast, or the softkey to decrease the contrast of the display. 2. When the desired display contrast level is obtained, press the softkey, located under the softkey Set Contrast Service menu. 3-12 HP EPM-441A/442A Service Guide...
Theory of Operation Introduction Introduction This chapter describes how each of the power meter’s assemblies operate. A block diagram is included at the end of the chapter giving you an overall view of the power meter’s operation. HP EPM-441A/442A Service Guide...
(HP Part Number 2110-0957). The fuse holder contains a spare fuse as standard on shipment. In addition there is also a fuse on the power supply assembly (HP Part Number 2110-0957). However, a transient suppressor is fitted to the line input module so that any mains transient blows the line module fuse before the power supply fuse.
Circuitry for the keyboard driver includes some damage protection, but it is basically a direct connection from the keypad row and column matrix to the microcontroller’s control lines. Three LEDs on the front panel are illuminated under the following conditions: HP EPM-441A/442A Service Guide...
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The microcontroller circuits that control all the above functions, and provide platform for the system software to run on, comprise the microcontroller itself, memory, and clock and logic circuits. The logic circuits have the function of ensuring the correct sequencing and decoding HP EPM-441A/442A Service Guide...
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A5 daughter assembly. The program memory for the microcontroller is FLASH EEPROM to allow for in-circuit programming. The static RAM is split into volatile and non-volatile blocks, with the power for the non-volatile RAM being connected to the permanent (battery backed) power supply. HP EPM-441A/442A Service Guide...
• the ribbon cable from A2J3 of the processor assembly which controls the LCD display. The power meter self tests contain display tests. These are accessed by System pressing Service Self Test Individual More Inputs Display HP EPM-441A/442A Service Guide...
A4 Interface Assembly The interface assembly contains the circuitry required for remote control of the power meter. This assembly supports the HP-IB interface with a protocol controller integrated circuit and two physical interface buffers. The assembly is connected to data, address, and control signals from the A2 processor assembly.
The daughter assembly is loaded vertically into the A2 processor assembly. It contains two slotted post connectors. Depending on whether you have an HP EPM-441A or an HP EPM-442A power meter, either one or two of these connectors are used respectively for the A6 measurement assembly(s).
The measurement assembly amplifies and converts the chopped AC signal produced by the power sensor (either HP 8480 series power sensors or HP E-series power sensors) into a 32 bit digital word. This digital word is proportional to the input RF power level applied to the power sensor. The measurement assembly also measures the sensor resistor voltage to detect whether a power sensor is present.
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The DSP chip controls the logic which sets the chopper driver voltage and frequency control. For the: • HP 8480 series power sensors this is 0 V and -10 V at 217 Hz. • HP E-series power sensors this is +7 V and -3 V at 434 Hz.
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Theory of Operation A6 Measurement Assembly 4-12 HP EPM-441A/442A Service Guide...
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Instrument Block Diagram HP EPM-441A/442A Service Guide...
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Theory of Operation A6 Measurement Assembly 4-14 HP EPM-441A/442A Service Guide...
To order parts contact your local Hewlett-Packard Sales and Service Office. To return your power meter for servicing at a qualified service center refer to “Contacting Hewlett-Packard” in Chapter 2 of the User’s Guide. HP EPM-441A/442A Service Guide...
Digit Power Supply Assembly 0950-2649 Processor Assembly E4418-60001 A301 Front Panel Assembly for: E4418-69017 HP EPM-441A and HP EPM-441A Option 002 A302 Front Panel Assembly for: E4418-69018 HP EPM-441A Option 003 A303 Front Panel Assembly for: E4419-69019 HP EPM-442A and...
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Description Designator Number Digit Channel A sensor cable Assy E4418-61009 Channel B sensor cable Assy E4418-61009 (HP EPM-442A only) Recorder Output Cable Assy E4418-61015 Front Power Reference Cable Kit E4418-61811 Rear Power Reference Cable Kit E4418-61813 HP EPM-441A/442A Service Guide...
The power meter’s firmware can be upgraded using a 300 or 700 series Unix workstation or a PC. The current version of firmware can be accessed by HP Service Centers using the World Wide Web. An executable file on the Unix workstation is also required.
Assembly and Disassembly Guidelines The guidelines in this section describe the removal and replacement of the major assemblies in the HP EPM-441A and HP EPM-442A power meters. Once an assembly has been replaced, refer to “Post-Repair Adjustments”, on page 3-3 to ensure that the correct performance tests and adjustments are carried out.
M3.5 machine screw (use a 9 lb/in T15 screw driver). All the protective earth wiring can be identified by the insulation color green with a yellow stripe. HP EPM-441A/442A Service Guide...
After replacing a processor board, the display brightness and contrast must be adjusted. See Chapter 3 “Adjustments”. Note Firmware should be downloaded to the instrument after the processor board is replaced. Refer to “Downloading Firmware”, on page 5-6. HP EPM-441A/442A Service Guide...
(When replacing these screws use a 21 lb/in T15 screw driver.) screws 5. Unscrew the HP-IB connector from the rear panel. (When replacing these screws use a 6 lb/in 9/32 in socket.) 6. Disconnect the Recorder Output cable.
2. Slide connector clamp in direction of arrow 3. Rotate connector clamp in direction of arrow 4. Position sensor flex circuit into connector in direction of arrow 6. Push clamp closed in direction of arrow HP EPM-441A/442A Service Guide 5-11...
1. Remove the A1 power supply assembly as shown on page 5-8. 2. Remove the pins which attach the fan to the chassis. 3. Remove the fan cable connector from the A2 processor assembly to release the fan. 5-12 HP EPM-441A/442A Service Guide...
The battery should not be subjected to short circuit of the battery terminals or to excessive heat. Do not recharge this battery or dispose of it by burning. Check local country regulatory requirements on the disposal of lithium batteries. HP EPM-441A/442A Service Guide 5-13...
Note After replacing a front panel assembly, the display brightness and contrast must be adjusted. Refer to Chapter 3 “Adjustments”. 5-14 HP EPM-441A/442A Service Guide...
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1. Remove the front panel from the power meter. (Refer to “Removing the A3 Front Panel Assembly”, on page 5-14 for details on removing the front panel.) 2. Replace the power sensor cable assembly(s) using the replacement kit. HP EPM-441A/442A Service Guide 5-15...
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Replaceable Parts Assembly and Disassembly Guidelines 5-16 HP EPM-441A/442A Service Guide...
2. Replace the power reference output cable assembly using the replacement kit and the torques indicated on the following diagrams. Fold up tab after assembly 25 lb/in 9 lb/in 6 lb/in HP EPM-441A/442A Service Guide 5-17...
5-10. 2. Replace the power sensor cable assembly(s) using the replacement kits. The inner recess on the power sensor cable is used to locate the circlip when assembling to the rear chassis. 5-18 HP EPM-441A/442A Service Guide...
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Replaceable Parts Assembly and Disassembly Guidelines HP EPM-441A/442A Service Guide 5-19...
(Refer to “Removing the A4 Interface Assembly”, on page 5-10.) 2. Replace the power reference cable assembly using the replacement kit and the torques indicated on the following diagrams. 25 lb/in tie wraps 6 lb/in 9 lb/in 5-20 HP EPM-441A/442A Service Guide...
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3-6 front panel repair 5-5 altitude characteristic 1-14 assembly part numbers 5-3 Hewlett-Packard offices ix battery replacement 5-13 HP E-series power sensor functional test 2-15 calibration cycle 2-4 interface test 2-14 caution v HP-IB characteristics 1-2 connector characteristic 1-13...
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5-8 performance test record 2-18 processor assembly 5-9 performance tests 2-2 replaceable parts 5-2 HP E-series power sensor functional test 2-15 returning for service xii HP E-series power sensor interface test 2-14 instrument accuracy test 2-7 power reference...
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5-6 user’s guides viii voltage 1-13 warm-up 1-2 warning v warranty iii weight of instrument 1-15 zero drift definition 1-12 drift of sensors, characteristic 1-7 zero set definition 1-12 specification 1-4 zero test 2-5 HP EPM-441A/442A Service Guide Index-3...
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Index-4 HP EPM-441A/442A Service Guide...