CN204680005U - Working state monitoring circuit - Google Patents
Working state monitoring circuit Download PDFInfo
- Publication number
- CN204680005U CN204680005U CN201420870633.3U CN201420870633U CN204680005U CN 204680005 U CN204680005 U CN 204680005U CN 201420870633 U CN201420870633 U CN 201420870633U CN 204680005 U CN204680005 U CN 204680005U
- Authority
- CN
- China
- Prior art keywords
- resistance
- amplifier
- level
- working state
- state monitoring
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Landscapes
- Amplifiers (AREA)
Abstract
The utility model provides a kind of working state monitoring circuit, belongs to field of information security technology.Working state monitoring circuit comprises: comparer, level translator and indicator, described comparer compares the quiescent operation point voltage of every grade in the white noise amplifier in Tempest device and threshold values respectively to judge that whether every grade of amplifier operation is normal, level translator is used for providing threshold voltage, and comparative result is converted to high level or low level; Indicator is used to indicate comparative result.The utility model is judged by the quiescent potential of working state monitoring circuit to the circuit in Tempest device, sees its DC static working point whether in normal voltage range, thus judges that whether the work of Tempest device is normal.The utility model structure is simple, and volume is little, effectively can judge the duty of Tempest device.
Description
Technical field
The utility model relates to a kind of working state monitoring circuit, particularly relating to a kind of observation circuit of the duty for monitoring the circuit in Tempest device, belonging to field of information security technology.
Background technology
Along with the high speed development of social informatization, electronic message unit is constantly progress also, thus meets the needs that in people's daily life, information is interconnected.But electronic message unit is while message exchange, all to produce certain electromagnetic radiation, thus cause two kinds of results: the leakage of electromagnetic mutual interference and installation electromagnetical information, wherein electromagnetic mutual interference problem is the problem of people's extensive concern, the time that it is found relatively early, electromagnetic compatibility (EMC) technology produces for solving electromagnetic mutual interference problem, there now have been the Theory and technology basis of comparative maturity.The problem of electromagnetic information leakage was just taken seriously and concern in nearly decades, and compared with electromagnetic mutual interference problem, electromagnetic information leakage treatment technology more lays particular emphasis on information security field, and it causes serious threat to the security work of information.
Although electromagnetic information leakage protection is with detection technique and electromagnetic compatibility technology all based on electromagnetic radiation problem, there is difference with general electromagnetic compatibility technology again in it.Electromagnetic information leakage protection and detection technique are compared with general electromagnetic compatibility problem, it more lays particular emphasis on the weak electromagnetic wave radiation of electronic information technology equipment and the leakage of information caused, and general electromagnetic compatibility problem focuses on the microwave radiation at work of electronic equipment and the interference to other electronic equipment, it is indifferent to the information entrained by electromagnetic wave.In addition, process electromagnetic information leakage protection and more require that there is professional detection and testing apparatus with test problems than electromagnetic compatibility problem.Further, electromagnetic information leakage protection will follow TEMPEST standard with detection.In a word, electromagnetic information leakage protection and detection technique are compared with the electromagnetic interference problem of electronic equipment, and its technical requirement is higher, electromagnetic environment is more complicated, testing standard is stricter.
Along with the development of internet, computing machine has become a part indispensable in people's life.But computing machine, can constantly to a large amount of electromagnetic wave signal of radiation in space during its work as the equipment of a kind of information processing and exchange.This electromagnetic wave signal given off likely carries the important information that computing machine is processing, thus brings huge hidden danger to information security issue.At work, its mainboard, display and all kinds of interface data wire, cable etc. all can launch intensity electromagnetic radiation in various degree to computing machine.From the angle of electromagnetic radiation theory, these useful informations given off all may be received and reduce.
For relating computer, it is same radiated electromagnetic wave at work, and security information wherein is just likely received thus decodes, the leakage of this mode, has walked around the fire wall of computing machine and hardware isolated in interior a series of safeguard procedures.In this case, even if computing machine is not connected with any miscellaneous equipment the data that can be stolen too, so be not difficult to block passage of divulging a secret through the computing machine of special electromagnetic information safety and Protection.In general, the primary radiation source of computing machine concentrates on cable part, if its cable can not provide effective shielding or filtering, the radiation intensity of its electromagnetic leakage will strengthen greatly.
Summary of the invention
For overcoming the shortcoming existed in prior art, goal of the invention of the present utility model is to provide a kind of working state monitoring circuit, it can monitor the duty of Tempest device effectively, and then the leakage of information effectively preventing power lead radiation and cause.
For realizing described goal of the invention, the invention provides a kind of working state monitoring circuit, it comprises: comparer, level translator and indicator, described comparer compares the quiescent operation point voltage of every grade in the white noise amplifier in Tempest device and threshold values respectively to judge that whether every grade of amplifier operation is normal, level translator is used for providing threshold voltage, and comparative result is converted to high level or low level; Indicator is used to indicate comparative result.
Preferably, described white noise amplifying circuit at least comprises two-stage.
Preferably, described white noise amplifying circuit is three grades.
Compared with prior art, the working state monitoring circuit that the utility model provides can monitor the duty of Tempest device effectively, and then the leakage of information effectively preventing power lead radiation and cause.
Accompanying drawing explanation
Fig. 1 provides the composition frame chart of Tempest device for the utility model;
The circuit diagram of the noise generating device that Fig. 2 provides for the utility model;
The composition frame chart of the work condition indicator that Fig. 3 provides for the utility model;
The circuit diagram of the white noise amplifier that Fig. 4 provides for the utility model;
The circuit diagram of the working state monitoring circuit that Fig. 5 provides for the utility model;
The circuit diagram of the low-pass filter that Fig. 6 provides for the utility model.
Embodiment
The utility model is described in detail below in conjunction with accompanying drawing.
Fig. 1 provides the composition frame chart of Tempest device for the utility model.As shown in Figure 1, the Tempest device that the utility model provides, comprise power-supply filter, AC/DC converter, noise-producing equipment, amplifier, low-pass filter and working state monitoring and display device, described power-supply filter is power line carrier wave information on filter out power line, preferably, the stopband operating frequency range of power-supply filter is 150KHz to 400MHz; AC/DC converter, for being converted into direct supply from the taking-up AC power on line of electric force, mainly produces+5V and+7V direct supply, for follow-up noise-producing equipment, amplifier, duty and display device provide direct supply.Described noise-producing equipment is for generation of white noise; Described amplifier produces white noise information for amplifying noise-producing equipment; Described low-pass filter is used for carrying out filtering to the white noise information that amplifier amplifies, and preferably, the passband operating frequency range of low-pass filter is 0MHz to 300MHz; Described white noise is coupled on power lead by coupling mechanism, and described coupling mechanism is inductive coupler or capacity coupler.
The circuit diagram of the noise generating device that Fig. 2 provides for the utility model.As shown in Figure 2, the noise generating device that the utility model provides comprises low-pass filter and white noise generator, described low-pass filter is made up of inductance L 5, electric capacity C9, electric capacity C15 and electric capacity C16, the cathode output end of+7V direct current supply line connects the first end of described inductance L 5, second end of inductance L 5 all connects the first end of electric capacity C9, electric capacity C15 and electric capacity C16, the second end ground connection of electric capacity C9, electric capacity C15 and electric capacity C16; Second end of inductance L 5 is connected to the first end of resistance R3, and second end of resistance R3 is connected to the emitter of the transistor Q1 in white noise generator, and that is ,+7V power supply provides electric energy then to white noise generator through low-pass filter filtering ripple.Described inductance L 5 exchanges logical direct current for hindering.The utility model adopts a jumbo electric capacity C9, and the mode that is in parallel of the electric capacity C15 of two low capacities and electric capacity C16 substantially increases the filtering characteristic of ripple.White noise generation device is made up of transistor Q1, the base earth of transistor Q1, and collector is unsettled, and emitter connects second end of current-limiting resistance R3, is connected to the first end of coupling capacitance C17 simultaneously, namely outwards provides white noise information by coupling capacitance C17.White noise generator utilizes the breakdown characteristics of PN junction to produce wide band white noise.
The composition frame chart of the work condition indicator that Fig. 3 provides for the utility model.As shown in Figure 3, work condition indicator comprises single-chip microcomputer, LCDs, clock chip, Hall element and working state monitoring circuit, can show the working time, flow through the electric current of power-supply filter and the current duty of Tempest device.Described Hall element flows through the electric current of power lead for monitoring, and export one with the voltage signal of current in proportion flowing through power lead, be then supplied to single-chip microcomputer; If the quiescent potential of working state monitoring main circuit to the white noise amplifier in Tempest device judges, see that whether its DC static working point is at normal voltage range; Single-chip microcomputer mainly processes the information of Hall element output and the information of working state monitoring circuit output, and shows in LCDs; Clock chip is for providing current temporal information, and the temporal information that single-chip microcomputer also provides according to clock chip is in the working time of the current date Hour Minute Second of liquid crystal display screen display and Tempest device.
The circuit diagram of the white noise amplifier that Fig. 4 provides for the utility model.As shown in Figure 4, the white noise amplifier that the utility model provides comprises three grades, the white noise information that described amplifier produces for amplifying noise generating device, and third stage amplifier successively dialogue noise information amplifies.First order amplifier, for amplifying the white noise signal that noise generating device produces, be supplied to second level amplifier after amplification to continue to amplify, it is made up of the first amplification chip MAR-8+ and peripheral circuit thereof, wherein, second end of the 1st pin butt coupling electric capacity C17 of the first amplification chip MAR-8+, the 2nd and 4 pin ground connection, the first end of the 3rd pin butt coupling electric capacity C18, provides drive singal through coupling capacitance C18 to second level amplifier; Power supply+5V provides suitable quiescent point to amplification chip MAR-8+ through biasing resistor R1 and inductance L 6 successively simultaneously, and electric capacity C11 and C12 plays the effect of ac short circuit ground connection.The white noise signal that second level amplifier amplifies for continuing amplification first order amplifier, be supplied to third level amplifier after amplification to continue to amplify, it is made up of the second amplification chip MAR-8+ and peripheral circuit thereof, wherein, second end of the 1st pin butt coupling electric capacity C18 of the second amplification chip MAR-8+, 2nd and 4 pin ground connection, the first end of the 3rd pin butt coupling electric capacity C19, provides drive singal through coupling capacitance C19 to third level amplifier; Power supply+5V provides suitable quiescent point to amplification chip MAR-8+ through biasing resistor R2 and inductance L 7 successively simultaneously, and electric capacity C13 and C14 plays the effect of ac short circuit ground connection, and electric capacity C10 is used for the ripple of filtering+5V power supply.The white noise signal that third level amplifier amplifies for amplifying second level amplifier, be supplied to rear class low-pass filter after amplification and carry out filtering, it is made up of the 3rd amplification chip MAR-8+ and peripheral circuit thereof, wherein, second end of the 1st pin butt coupling electric capacity C23 of the 3rd amplification chip MAR-8+, the first end of electric capacity C23 is connected to second end of resistance R9, and the first end of resistance R9 is connected to second end of electric capacity C19; Resistance R9 is for controlling output power; 2nd and the 4 pin ground connection of the 3rd amplification chip MAR-8+, the first end of the 3rd pin butt coupling electric capacity C24, provides signal through coupling capacitance C24 to low-pass filter; Power supply+5V provides suitable quiescent point to amplification chip MAR-8+ through biasing resistor R4 and inductance L 8 successively simultaneously, and electric capacity C21 and C22 plays the effect of ac short circuit ground connection, and electric capacity C20 is used for the ripple of filtering+5V power supply.
The circuit diagram of the working state monitoring circuit that Fig. 5 provides for the utility model.As shown in Figure 5, the working state monitoring circuit that the utility model provides: comparer, level translator and indicator, the quiescent operation point voltage of the every one-level of three grades in described comparer difference comparison amplifier and threshold values are to judge that whether amplifier operation is normal, level translator is used for providing threshold voltage, and comparative result is converted to high level or low level; Whether indicator is used to indicate amplifier operation normal, when pilot lamp is bright, represents working properly, when pilot lamp does not work, represents that work is abnormal.Comparer comprises the first electric switch, the second electric switch, the 3rd electric switch, the 4th electric switch, the 5th electric switch and the 6th electric switch, wherein, first electric switch is made up of transistor Q4, resistance R14, resistance R16 and diode D5, the emitter of transistor Q4 is connected to power supply+5V through resistance R14, collector is connected to ground through resistance R16, also be connected to the negative pole of diode D5, base stage is connected to the test side DT1 of the first order amplifier in amplifier; The positive pole of diode D5 is connected to the input end of level translator, i.e. the intermediate node of resistance R7 and resistance R10; Second electric switch is made up of transistor Q5, resistance R17, resistance R21 and diode D8, the emitter of transistor Q5 is connected to power supply+5V through resistance R17, collector is connected to ground through resistance R21, also be connected to the negative pole of diode D8, base stage is connected to the test side DT2 of the second level amplifier in amplifier; The positive pole of diode D8 is connected to the input end of level translator, i.e. the intermediate node that is in series of resistance R7 and resistance R10; 3rd electric switch is made up of transistor Q6, resistance R18, resistance R22 and diode D9, the emitter of transistor Q6 is connected to power supply+5V through resistance R18, collector is connected to ground through resistance R22, also be connected to the negative pole of diode D9, base stage is connected to the test side DT3 of the third level amplifier in amplifier; The positive pole of diode D9 is connected to the input end of level translator, i.e. the intermediate node that is in series of resistance R7 and resistance R10.4th electric switch is made up of diode D1, and the negative pole of diode D1 is connected to the test side DT1 of the first order amplifier in amplifier, and positive pole is connected to the input end of level translator, i.e. the intermediate node of resistance R7 and resistance R10; 5th electric switch is made up of diode D2, and the negative pole of diode D2 is connected to the test side DT2 of the second level amplifier in amplifier, and positive pole is connected to the input end of level translator, i.e. the intermediate node of resistance R7 and resistance R10.6th electric switch is made up of diode D3, and the negative pole of diode D3 is connected to the test side DT3 of the third level amplifier in amplifier, and positive pole is connected to the input end of level translator, i.e. the intermediate node that is in series of resistance R7 and resistance R10.
Level translator is made up of resistance R7, resistance R10, electric capacity C26, transistor Q2, resistance R5, resistance R8, resistance R11, resistance R13, transistor Q3 and resistance R6, wherein, resistance R7 and R10 is in series, and be connected between power supply+5V and ground, its intermediate node is the input end of level translator, electric capacity C26 is also connected in resistance R10 two ends, for filtering ripple, to prevent misoperation.Resistance R5 and R8 is in series, and be connected between power supply+5V and ground, the emitter that its intermediate node is transistor Q2 provides a suitable quiescent point, and the collector of transistor Q2 is through resistance R13 ground connection, and base stage is connected to the intermediate node that resistance R7 and R10 is in series.Transistor Q3 works on off state, and its collector is connected to power supply+5V through resistance R6, grounded emitter, and base stage is connected to the collector of transistor Q2 through resistance R11.
The quiescent point of amplification chip MAR-8+ is when 2.8-4V, be in normal operating conditions, when first order normal amplifier operation, the transistor Q4 being connected to DT1 is in conducting state, diode D5 is in cut-off state, diode D1 is in cut-off state, the intermediate node voltage that resistance R7 and R10 is in series is unaffected, transistor Q2 is in cut-off state, the voltage at resistance R13 two ends is zero, transistor Q3 is also in cut-off state, R6 and R23 intermediate node voltage is+5V, for an input end of single-chip microcomputer provides high level, simultaneously light emitting diode D13 connects electricity and luminous, represent that first order amplifier operation is normal.When the quiescent point of the first amplifier MAR-8+ is higher than 4V, be in abnormal operating state, the diode D1 being connected to DT1 is in cut-off state, transistor Q4 is in cut-off state, diode D5 is in conducting state, the intermediate node voltage that resistance R7 and R10 is in series becomes by the impact that Q4 ends and is less than+2V, transistor Q2 is in conducting state, the voltage at resistance R13 two ends is greater than 1V, transistor Q3 is in saturation conduction state, R6 and R23 intermediate node voltage is less than 1V, for an input end of single-chip microcomputer provides low level, simultaneously light emitting diode D13 power-off and not luminous, represent that first order amplifier operation is abnormal, when the quiescent point of the first amplification chip MAR-8+ is lower than 2.8V, be in abnormal operating state, the diode D1 being connected to DT1 is in conducting state, transistor Q4 is in conducting state, diode D5 is in cut-off state, the intermediate node voltage that resistance R7 and R10 is in series becomes by the impact of D1 conducting and is less than+3.5V, transistor Q2 is in conducting state, the voltage at resistance R13 two ends is greater than 1V, transistor Q3 is in saturation conduction state, R6 and R23 intermediate node voltage is less than 1V, for an input end of single-chip microcomputer provides low level, light emitting diode D13 power-off and not luminous, represent that first order amplifier operation is abnormal.
When second level normal amplifier operation, the transistor Q5 being connected to DT2 is in conducting state, diode D8 is in cut-off state, diode D2 is in cut-off state, the intermediate node voltage that resistance R7 and R10 is in series is unaffected, transistor Q2 is in cut-off state, the voltage at resistance R13 two ends is zero, transistor Q3 is also in cut-off state, R6 and R23 intermediate node voltage is+5V, for an input end of single-chip microcomputer provides high level, simultaneously light emitting diode D13 connects electricity and luminous, and expression second level amplifier operation is normal.When the quiescent point of the second amplification chip MAR-8+ is higher than 4V, be in abnormal operating state, the diode D2 being connected to DT2 is in cut-off state, transistor Q5 is in cut-off state, diode D8 is in conducting state, the intermediate node voltage that resistance R7 and R10 is in series becomes by the impact that Q5 ends and is less than+2V, transistor Q2 is in conducting state, the voltage at resistance R13 two ends is greater than 1V, transistor Q3 is in saturation conduction state, R6 and R23 intermediate node voltage is less than 1V, for an input end of single-chip microcomputer provides low level, light emitting diode D13 power-off and not luminous, represent that second level amplifier operation is abnormal, when the quiescent point of the second amplification chip MAR-8+ is lower than 2.8V, be in abnormal operating state, the diode D2 being connected to DT2 is in conducting state, transistor Q5 is in conducting state, diode D8 is in cut-off state, the intermediate node voltage that resistance R7 and R10 is in series becomes by the impact of D2 conducting and is less than+3.5V, transistor Q2 is in conducting state, the voltage at resistance R13 two ends is greater than 1V, transistor Q3 is in saturation conduction state, R6 and R23 intermediate node voltage is less than 1V, for an input end of single-chip microcomputer provides low level, light emitting diode D13 power-off and not luminous, represent that second level amplifier operation is abnormal.
When third level normal amplifier operation, the transistor Q6 being connected to DT3 is in conducting state, diode D9 is in cut-off state, diode D3 is in cut-off state, the intermediate node voltage that resistance R7 and R10 is in series is unaffected, transistor Q2 is in cut-off state, resistance R13 both end voltage is zero, transistor Q3 is also in cut-off state, R6 and R23 intermediate node voltage is+5V, for an input end of single-chip microcomputer provides high level, simultaneously light emitting diode D13 connects electricity and luminous, and expression third level amplifier operation is normal.When the quiescent point of the 3rd amplification chip MAR-8+ is higher than 4V, be in abnormal operating state, the diode D3 being connected to DT3 is in cut-off state, transistor Q6 is in cut-off state, diode D9 is in conducting state, the intermediate node voltage that resistance R7 and R10 is in series becomes by the impact that Q6 ends and is less than+2V, transistor Q2 is in conducting state, the voltage at resistance R13 two ends is greater than 1V, transistor Q3 is in saturation conduction state, R6 and R23 intermediate node voltage is less than 1V, for an input end of single-chip microcomputer provides low level, simultaneously light emitting diode D13 power-off and not luminous, represent that second level amplifier operation is abnormal, when the quiescent point of the 3rd amplification chip MAR-8+ is lower than 2.8V, be in abnormal operating state, the diode D3 being connected to DT3 is in conducting state, transistor Q6 is in conducting state, diode D9 is in cut-off state, the intermediate node voltage that resistance R7 and R10 is in series becomes by the impact of D3 conducting and is less than+3.5V, transistor Q2 is in conducting state, the voltage at resistance R13 two ends is greater than 1V, transistor Q3 is in saturation conduction state, R6 and R23 intermediate node voltage is less than 1V, for an input end of single-chip microcomputer provides low level, simultaneously light emitting diode D13 power-off and not luminous, represent that third level amplifier operation is abnormal.
The circuit diagram of the low-pass filter that Fig. 6 provides for the utility model, as shown in Figure 6, the low-pass filter that the utility model provides is 7 rank Tchebyscheff filters, is made up of inductance L 10, inductance L 11, inductance L 9, inductance L 12, electric capacity C27, electric capacity C28, electric capacity C29, electric capacity C25.Because triode punctures produced noise signal, broader bandwidth, if without restriction, probably affect other signal, so after generation noise, passed through low-pass filter, make its bandwidth restriction within the specific limits, the preferred passband operating frequency range of the utility model is 0MHz to 300MHz.
Below done to elaborate to design of the present utility model and example by reference to the accompanying drawings; but those skilled in the art will be appreciated that; under the prerequisite not departing from the utility model design, any improvement of making based on the utility model and convert the content still belonged in the utility model protection domain.
Claims (3)
1. a working state monitoring circuit, it is characterized in that, comprise: comparer, level translator and indicator, described comparer compares the quiescent operation point voltage of every grade in the white noise amplifier in Tempest device and threshold values respectively to judge that whether every grade of amplifier operation is normal, level translator is used for providing threshold voltage, and comparative result is converted to high level or low level; Indicator is used to indicate comparative result.
2. working state monitoring circuit according to claim 1, is characterized in that, described white noise amplifying circuit at least comprises two-stage.
3. working state monitoring circuit according to claim 2, is characterized in that, described white noise amplifying circuit is three grades.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420870633.3U CN204680005U (en) | 2014-12-29 | 2014-12-29 | Working state monitoring circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420870633.3U CN204680005U (en) | 2014-12-29 | 2014-12-29 | Working state monitoring circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN204680005U true CN204680005U (en) | 2015-09-30 |
Family
ID=54179680
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201420870633.3U Active CN204680005U (en) | 2014-12-29 | 2014-12-29 | Working state monitoring circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN204680005U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104484263A (en) * | 2014-12-29 | 2015-04-01 | 李大庆 | Working condition monitoring circuit |
-
2014
- 2014-12-29 CN CN201420870633.3U patent/CN204680005U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104484263A (en) * | 2014-12-29 | 2015-04-01 | 李大庆 | Working condition monitoring circuit |
| CN104484263B (en) * | 2014-12-29 | 2017-12-15 | 李大庆 | Working state monitoring circuit |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN204680005U (en) | Working state monitoring circuit | |
| CN104467922A (en) | Information leakage prevention device | |
| CN203358368U (en) | Fault latch circuit of electric car controller | |
| CN203101558U (en) | Fault screening device for electric equipment | |
| CN204376901U (en) | Tempest device | |
| CN204376866U (en) | Operating state classified Monitoring circuit | |
| CN204374278U (en) | Work condition indicator | |
| CN104484263A (en) | Working condition monitoring circuit | |
| CN104535821A (en) | Working state indicating device | |
| CN207116332U (en) | Safety type relay control circuit | |
| CN104539283A (en) | Operating state classification monitoring circuit | |
| CN203745546U (en) | Ground resistance monitoring device | |
| CN103376383B (en) | Ground wire observation circuit and system | |
| CN207895022U (en) | The connection detection circuit of electromagnetic lock | |
| CN205826162U (en) | A kind of fiber optic temperature analyser | |
| CN109637095A (en) | A kind of water level detecting alarm control circuit | |
| CN102843531A (en) | Drive control circuit and television | |
| CN208325149U (en) | A kind of shared electric car protection alarm device | |
| CN206272215U (en) | A kind of overload protecting circuit | |
| CN207926157U (en) | Wisdom formula electrical safety hidden danger monitoring and predicting and service system | |
| CN205139211U (en) | Prevent high frequency and steal electric terminal box | |
| CN206045237U (en) | A kind of Internet of Things fire control system | |
| CN205003220U (en) | Lightning current HF reject monitoring devices | |
| CN204347175U (en) | A kind of lightning current HF reject device with monitoring function | |
| CN108109307A (en) | A kind of triode drive-type anti-theft alarm system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CB03 | Change of inventor or designer information |
Inventor after: Li Daqing Inventor after: Liao Xiaoyong Inventor before: Li Daqing |
|
| CB03 | Change of inventor or designer information | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20180425 Address after: No. 87 Xiangshan South Road, Haidian District, Beijing Patentee after: Liao Xiaoyong Address before: 100086 1602 unit, 35 building, 23 hospital, new street, Haidian District, Beijing. Patentee before: Li Daqing |
|
| TR01 | Transfer of patent right |