JJG 433-2004 Phase Comparator Verification Procedure JJG433-2004 Standard download decompression password: www.bzxz.net
This procedure is applicable to the initial verification, subsequent verification and in-use inspection of linear phase comparators.

People's Republic of China National Metrology Verification Regulation JJG 433—2004
Phase Comparators
2004-11-09 Issued
Implementation on 2005-05-09
Issued by the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China JJG 433—2004
Verification Regulation
of Phase Canparators
JJG 433——20(4
Replaces JJG433—1986
This Regulation was approved by the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China on November (9, 2004) Approved by: and implemented from May 9, 2005.
Responsible unit: National Technical Committee for Low-frequency Metrology Main drafting unit: Second Institute of Second Gate of First Academy of Aerospace Science and Industry Corporation Full drafting unit: China Academy of Metrology This regulation is entrusted to the National Technical Committee for Time and Frequency Metrology to be responsible for the interpretation of this regulation Main drafter:
Xu Yueqing
Jiang Dongwei
Participating drafter:
Zhao Liangruo
JJG433-2004
(Second Institute of Second Gate of Second Academy of Aerospace Science and Industry Corporation)
(Second Institute of Second Gate of Second Academy of Aerospace Science and Industry Corporation)
|(China Institute of Metrology)
3 Meter performance requirements
3.1 Frequency range
3.2 Input sensitivity
3.3 Phase drift
3.4 ​​Nonlinearity
3.5 Discriminator dead zone
4 General technical requirements
4.1 Appearance and logo
4.2 Other requirements
5 Meter basic control
5.1 Verification conditions
5.2 Verification items and verification methods
5.3 Processing of verification results
5.4 Verification cycle
JJG 433-2604
Appendix A Verification Certificate and Verification Result Notice (Inner Page) Format..(1)
1 Scope
JJG433—2004
Verification Procedure for Phase Comparator
This procedure applies to the first-time verification and subsequent verification of linear comparators and in-use inspection: 2 Overview
Linear comparators are special equipment for precise time-frequency measurement. The principle is to use a phase detector to convert the phase difference of two inputs with the same nominal frequency into voltage, and then use a paper tape digital recorder to record the voltage changes. By observing the change in phase difference within a period of time, the average frequency deviation of the period can be derived. The continuous phase comparator (hereinafter referred to as the phase comparator) is used to measure The frequency accuracy, frequency drift rate and long-term stability of various atomic frequency standards and high-precision crystal oscillators are as follows:
3 Metrological performance requirements
3.1 Frequency range: 100kHz-10H
3.2 Input sensitivity: 300mV (ms) (input impedance 500) 3.3 Machine position drift (for 5MH): 4 (observation time 1) 3.4 Nonlinearity (for 5MI): ≤4
3.5 Detector dead zone (for 5Mz): 10m
4 General technical requirements
4.1 External markings
The front and rear of the phase comparator should have the manufacturer's name, calibrator model, product number, marking and source requirements.
4.2 Other requirements
4.2.1 The buttons, input ports and control ports of the phase comparator should have clear markings. 4.2.2 The first calibration of the phase comparator should be accompanied by the instruction manual, and the subsequent calibration should be accompanied by the instruction manual and the calibration certificate submitted to the inspection.
5 Control of measuring instruments
Including the first calibration, subsequent calibration and in-use inspection, 5.1 Calibration conditions
5.1.1 Working environment
5.1.1.1 Temperature: any point within 10℃-30%, the temperature fluctuation during the calibration should not exceed ±25.1.1.2 Relative humidity: ≤.R%
5.1.1.3 AC power supply: 220 (110%) V, (50±1) H5.1.1.4 Electromagnetic interference and mechanical vibration of the instrument should be avoided during the use of the instrument. 5.1.2 Equipment for use
5.1.2.1 Reference frequency standard
JJG 433—2004
High stability crystal shifter can be used as atomic frequency standard: 5.1.2.2 Frequency combiner or device
Range frequency: should cover the measuring range of phase comparator. Output level: 1mV (1m)~1(m) (500 load) with external frequency standard function.
5.1.2.3 Resolution of the calibration micrometer or precision scale: Ing
Maximum allowable eddy error: ±0.1m
5.2 Inspection date and location
5.2.1 Inspection items
Item date
Appearance and normality inspection
Problem range
Counter source
Non-carboxylic
Inspection cabinet external area
Bitter inspection
Jiang: ""Inspection item", "" is optional.
5.2.2 Appearance and performance inspection
After carbon calibration
Use the central control
5.3.2.1 The inspected comparator should not be damaged by mechanical damage, all functions and switches should be able to work normally, the signal input frequency should be stable, and the control port connection should be reliable. 5.2.2.2 Turn on the power supply. Connect the two comparator signals that meet the requirements of the inspected comparator input frequency and input voltage. All functions of the comparator cabinet should be normal, and the measurement and full scale adjustment can be adjusted normally. Various indicator lights and measurement display should be clearly visible. bzxz.net
5.2.2.3 Control interface inspection
For comparators with external control functions, connect the control cable according to the requirements of the control manual. The comparator should be able to work normally through the control indicator.
5.2.3 Verification of input sensitivity in frequency range 5.2.3.1 Input sensitivity refers to the minimum input signal voltage required for the normal operation of the phase comparator. 5.2.3.2 Connect the instrument as shown in Figure 1 and preheat it according to the provisions of the instrument manual. Select the upper limit frequency (10MH), lower limit frequency (100kHz, 50MHz, etc.) within the working frequency range of the phase comparator to be tested, and measure the frequency range and input sensitivity. 5.2.3.3 Connect the signal output by the reference frequency standard to the external frequency standard input terminal of frequency synthesizers I and II, adjust the frequency synthesizer II output to the upper limit frequency of the tested comparator, such as 10M, and adjust the output voltage of frequency synthesizer II to 2. The reference frequency standard is included in the reduction rate of 1. The frequency synthesizer is G433-2H4. The reference frequency synthesizer is used as the reference frequency synthesizer. The output voltage of the tested comparator is adjusted to a value smaller than 0.3V (), and the output voltage is adjusted to 0.7 (). The frequency synthesizer is gradually reduced. The voltage of the screening device is far away from the minimum input voltage of the phase comparator (such as 0 (, and then increase the input signal accuracy of the rate synthesizer to 1, the system needs to make a positive comparison, record the output frequency position and amplitude value of the rate synthesizer, and compare the sensitivity of the phase comparator A to the auxiliary terminal of the phase comparator B. The input frequency range of this input should be within the range of the rate range. 5.2.3.4 The method of the same column is to verify the lower limit frequency point and the middle frequency point of the phase comparator and its beat number. 5.2.4 Verification of the ancestral position drift
5.2 .4.1 Phase drift refers to the change in the phase position of the phase comparator. 5.2.4.2 According to Figure 2, add the test sample according to the instrument description and the preset potential transmitter or the micro-shifter to be tested. 5.2.4.3 Adjust the zero scale and full scale of the phase comparator respectively, refer to the 5MH standard, and make the potential difference between A and the input signal of the terminal equal to 1. 5.2.4.4 The recorded value displayed by the tested phase comparator is P, then the corresponding phase The phase difference is 2X, and the conversion of AP and is calculated according to the formula.
In the formula,
——the full-scale value of the phase comparator;
——the zero-scale value of the phase comparator
T—the period of the phase difference input by the detected phase comparator, the maximum integral of the phase difference within the measurement time (1×), is the phase drift of the controlled phase comparator. 5.2.5 Verification of the phase-integrated region and non-relay
5.2.5.1 The phase-integrated region refers to the region where the zero-scale and full-scale of the phase comparator cannot work normally when the detected phase comparator inputs a positive working signal.
JIC 433—2004
The phase-comparison characteristic of the phase comparator is theoretically -100%, and the deviation of the actual measurement result from the theoretical straight line is called the nonlinearity of the phase comparator
The phase-integrated region and non-relay of the phase comparator are verified at the input frequency point 5 of the phase comparator. 5.2.5.2 Connect the instrument as shown in Figure 2, and preheat the instrument as specified in the instrument manual: 5.2.5.3 Adjust the zero scale and full scale values ​​of the comparator according to the comparator manual. Starting from the detected comparator indication (record) of Li, gradually change the phase of the output signal of the phase micro-circuit. The unit is. (1) Increase T in steps of 2 until the comparator responds normally. If it steps 10 times, then the phase difference of the two input signals at this time is
AT, =n × 2ns
. The phase difference measured by the comparator is. , the measurement error is 8. =AX.-AT
(2) Continue to adjust the phase of the phase microcoupler until it is changed to 10ns, a total of 16 steps, record the total phase difference 7 of the two input signals after each step and the total phase difference 2X. measured by the phase comparator, and calculate the measurement error 5AT -AT +x l0na
#=1, 2, ., 16
8,-AX:AT.
(3) Change the step size to 2: until the indication of the phase comparator does not change with the change (or to degrees), then step "m times: record the total phase difference A7 of the previous two input signals and the total phase difference measured by the phase comparator.,, and calculate the measurement error
AT = aT,+ [60ns + (m - 1) ×2ngIf the phase difference between the two input signals changes by 20°, the phase comparator still works normally, then △T = 20°. S = AX-A.
At the same time, the color T is reduced to the phase comparison dead zone of the phase comparator.
The nonlinearity is calculated as follows:
5.3 Treatment of verification results
AT, - 2m5 - AT
AT =AT -2ms +AT
A phase comparator that passes the verification according to the requirements of this regulation shall be issued with a verification certificate; if it fails the verification, a verification result notice shall be issued, and the unqualified items shall be indicated.
5.4 Verification cycle
The verification cycle of the phase comparator shall generally not exceed 1 year. 4
Appendix A
J.IG 433-20 No. 4
Verification certificate and verification result notice (internal) format AI (Verification certificate (internal) format
1. Frequency standard input recording micro information (5M load, effective value) measurement channel
Pass A
2. Machine drift
3. Machine detection suburb
4. Nonlinearity
Temperature:
Input frequency
Relative humidity:
JJG 433
AZVerification auxiliary notice (internal) format
Contents are the same as Appendix 41, indicating the unqualified items,
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