CRAC Bilingual Exam Manual (Class A / B / C) | 中国业余无线电台操作技术能力验证英中对照手册
The complete CRAC Class A question bank — 669 questions in exam reading order. Click any question to jump to its bilingual Q&A card.
Radio Management Laws and Regulations无线电管理法规与规章 · 26 questions
- The administrative regulation specifically addressing radio management in our country, and its enacting author…
- The document specifically governing amateur radio stations in our country, and its enacting authority, are, re…
- The authority legally responsible for the supervision and administration of amateur radio stations in our coun…
- The regulatory document that specifically defines the radio-management terms "amateur service", "amateur-satel…
- When did the latest Measures for the Administration of Amateur Radio Stations (《业余无线电台管理办法》) come into force?
- The process of entering a specific frequency band into the Table of Frequency Allocations, stipulating that th…
- The process of specifying that a radio frequency or channel is to be used, within a designated area and under …
- The process of authorizing a radio station to use a radio frequency or channel under specified conditions is c…
- In the Table of Frequency Allocations, when a band is marked as allocated to multiple services, those services…
- Radiation means energy flow from any source emitted outward in the form of radio waves. Which of the following…
- Emission means: radiation or radiation products produced by a radio transmitting station. Which of the followi…
- Which of the following statements about general radio terminology is correct? (Choose all that apply.)
- Which of the following statements about an amateur radio station is correct?
- Which of the following statements about the amateur service and the amateur-satellite service is correct? (Cho…
- Which of the following statements about the definition of an amateur radio operator is correct? (Choose all th…
- Which of the following statements about emission class is correct? (Choose all that apply.)
- Which of the following statements about single-sideband (SSB) emission is correct?
- Which of the following statements about the definition of interference is correct? (Choose all that apply.)
- Which of the following statements about the definition of harmful interference is correct? (Choose all that ap…
- Which of the following statements about secondary-service stations is correct? (Choose all that apply.)
- The international organization that coordinates international radio management is:
- The International Amateur Radio Union (IARU) supports its member societies in viewing the development of amate…
- Which of the following communications does NOT fall within the scope of telecommunication?
- Which of the following statements about radio communication is correct?
- Which of the following statements about terrestrial radio communication is correct?
- Radio waves are:
Amateur Station Establishment and Approval业余无线电台的设置与审批 · 23 questions
- The materials an individual must submit to the radio management authority to establish and operate an amateur …
- The materials an organization must submit to the radio management authority to establish and operate an amateu…
- When establishing and operating an amateur radio station, which of the following conditions comply with the re…
- Where a person intends to establish and operate an amateur radio station using self-made, modified, or assembl…
- With respect to establishing and operating short-wave amateur radio stations above 15 W, and other important a…
- What particulars are recorded in an amateur radio station license? (Choose all that apply.)
- The validity period of an amateur radio station license does not exceed:
- Which of the following statements about the amateur radio station license is correct? (Choose all that apply.)
- Which of the following statements about the new Measures for the Administration of Amateur Radio Stations (《业余…
- The age requirement for independently operating an amateur radio station with transmitting capability is:
- The age requirement for an individual applying to establish and operate an amateur radio station with transmit…
- To establish and operate an amateur radio station with a fixed site, an application should be submitted to whi…
- To establish and operate an amateur radio station without a fixed site, an application should be submitted to …
- To establish and operate an amateur radio station, the conditions that must be satisfied for establishing one …
- Where an amateur radio station license needs to continue to be used after its validity period expires, an appl…
- Where the particulars recorded in an amateur radio station license are to be changed, which procedure should b…
- When ceasing to use an amateur radio station, the license cancellation procedure should be handled with which …
- Which of the following statements about ceasing to use an amateur radio station is correct? (Choose all that a…
- Which of the following statements about amateur repeaters is INCORRECT? (Choose all that apply.)
- Which of the following statements about amateur beacon stations is INCORRECT? (Choose all that apply.)
- Which of the following statements about amateur repeaters are correct? (Choose all that apply.)
- Which of the following statements about establishing an amateur repeater is correct? (Choose all that apply.)
- The establishment and technical parameters of an amateur repeater should satisfy the following key conditions:
Operator Capability Verification操作技术能力验证 · 20 questions
- The organizations that may organize the Class A and Class B amateur radio operator-capability verification are…
- The organization responsible for organizing the Class C amateur radio operator-capability verification is:
- Which of the following statements is correct regarding participating in amateur radio operator-capability veri…
- The document certifying amateur radio operator-capability of each class is:
- The national radio management authority and its entrusted organizations may organize and implement the followi…
- Into which classes is amateur radio operator-capability divided?
- The main difference between amateur radio stations of different classes lies in: (Choose all that apply.)
- The permitted operating frequency range and maximum transmit power for a Class A amateur radio station are:
- For a person who has obtained the Class B amateur radio operator certificate, the operating frequency bands an…
- For a person who has obtained the Class C amateur radio operator certificate, the operating frequency bands an…
- Which of the following requirements must be met to participate in the Class A amateur radio operator-capabilit…
- Which of the following requirements must be met to participate in the Class B amateur radio operator-capabilit…
- Which of the following requirements must be met to participate in the Class C amateur radio operator-capabilit…
- A person who has obtained the Class A amateur radio operator certificate may apply to establish and operate th…
- A person who has obtained the Class B amateur radio operator certificate may apply to establish and operate th…
- A person who has obtained the Class C amateur radio operator certificate may apply to establish and operate th…
- Which of the following statements about conducting special technical tests, QSOs, and similar activities is co…
- Which of the following is correct regarding minors establishing and operating amateur radio stations? (Choose …
- Which of the following statements about amateur radio operator-capability verification is correct? (Choose all…
- Regarding persons who lawfully obtained a Class B amateur radio operator-capability verification certificate b…
Amateur Station Call Signs业余无线电台呼号 · 29 questions
- The method prescribed by the Measures for the Administration of Amateur Radio Stations (《业余无线电台管理办法》) for corr…
- The process for issuing an amateur radio station call sign is:
- When the radio management authority issues an amateur radio station license, if the applicant already holds an…
- When an amateur radio station call sign is discontinued, which of the following statements is correct? (Choose…
- Before a cancelled call sign is re-allocated, if the applicant applies again to establish and operate an amate…
- When operating (transmitting) on another person's lawfully established amateur radio station, which of the fol…
- Which of the following conditions allow the temporary use of another amateur radio station's call sign? (Choos…
- Which of the following statements about an amateur radio station call sign is correct? (Choose all that apply.…
- Which of the following statements about the amateur radio station call-sign prefix is correct? (Choose all tha…
- Which of the following statements about station type (the second part of the call sign) is correct? (Choose al…
- Which of the following statements about the district number (the third part of the call sign) is correct? (Cho…
- Which of the following statements about the call-sign suffix (the fourth part) is correct? (Choose all that ap…
- When provincial radio management authorities issue general amateur radio station call signs, which of the foll…
- If an amateur radio operator is dissatisfied with the call sign already issued to them, may they apply for a d…
- The method for determining the available ranges of call-sign prefix letters and suffix characters in each loca…
- Which of the following statements about using an amateur radio station call sign is correct? (Choose all that …
- An amateur radio station call sign consists of which of the following parts? (Choose all that apply.)
- The Measures for the Administration of Amateur Radio Stations (《业余无线电台管理办法》) require an amateur station to act…
- In an amateur radio contact, may the district code plus suffix taken from your own or the other station's call…
- Regarding China's amateur radio station district numbers, the province (autonomous region / municipality direc…
- Regarding China's amateur radio station district numbers, the provinces with district number 2 are: (Choose al…
- Regarding China's amateur radio station district numbers, the provinces with district number 3 are: (Choose al…
- Regarding China's amateur radio station district numbers, the provinces with district number 4 are: (Choose al…
- Regarding China's amateur radio station district numbers, the provinces with district number 5 are: (Choose al…
- Regarding China's amateur radio station district numbers, the provinces with district number 6 are: (Choose al…
- Regarding China's amateur radio station district numbers, the provinces with district number 7 are: (Choose al…
- Regarding China's amateur radio station district numbers, the provinces with district number 8 are: (Choose al…
- Regarding China's amateur radio station district numbers, the provinces with district number 9 are: (Choose al…
- Regarding China's amateur radio station district numbers, the provinces with district number 0 are: (Choose al…
Lawful Establishment and Operation业余无线电台的法定设置与使用 · 36 questions
- The necessary step for lawfully establishing and operating an amateur radio station is:
- The statutory purpose of an amateur radio station is:
- When applying to establish and operate an amateur radio station equipped with multiple transmitting devices, y…
- The essential technical measure for an amateur repeater is:
- A group has lawfully established an amateur repeater. The correct practice is:
- The principle for choosing the same-band transmit/receive offset of a 144 MHz or 430 MHz analog FM amateur rep…
- The radio transmitting equipment used by an amateur radio station must meet the following conditions: (Choose …
- "I am not an amateur radio operator; I applied for a station just for driving convenience and don't need to fo…
- An amateur operator hears what is clearly man-made interfering transmission from a non-amateur station on an a…
- Retransmitting broadcast stations, internet chat, telephone calls, or other stations' contact signals through …
- An amateur station relays messages for other persons, units, or organizations during communication. The correc…
- An amateur radio association broadcasts public-interest notices and technical-training lectures to its members…
- The correct practice regarding the language used during amateur radio communications is:
- May a person who possesses the operating-technical capability prescribed by the national radio management auth…
- Persons who have not obtained the corresponding amateur radio station license or the corresponding operating-t…
- The legal responsibility that an amateur radio station licensee bears for their radio transmitting equipment i…
- The rule that an amateur radio operator must follow when using amateur radio receiving equipment is:
- When an amateur radio operator inadvertently receives information from non-amateur and non-amateur-satellite s…
- May an amateur radio station transmit signals received from broadcast stations, recordings of audio/video prog…
- The state's attitude toward using amateur radio stations to publish or disseminate information that violates t…
- A taxi installs an amateur radio station and uses it to relay information about passengers; the nature of this…
- The proper attitude toward using amateur radio communications to promote amateur radio products or advance oth…
- Using your own amateur station to deliberately jam the normal communications of other amateur stations with a …
- Whether amateur radio activities are conducted in an orderly manner affects the safety and effectiveness of ra…
- Amateur radio stations may be used for the following purposes:
- The group of people who meet the basic conditions of an amateur radio operator is:
- Amateur radio stations are prohibited from engaging in the following activities: (Choose all that apply.)
- Amateur radio stations shall comply with which of the following provisions: (Choose all that apply.)
- Which of the following uses of an amateur radio station exceed the rule of transmitting/receiving signals with…
- Which of the following radio transmitting equipment that has NOT obtained type approval may NOT be established…
- In using an amateur radio station, one may not engage in the following activities: (Choose all that apply.)
- In using an amateur radio station, one shall conform to the following provisions: (Choose all that apply.)
- Regarding the language used during amateur radio communications, the correct practices are: (Choose all that a…
- Which of the following statements about emergency communication by amateur radio stations is correct?
- The conditions under which an amateur radio station is permitted to communicate with non-amateur radio station…
- Amateur radio operators, in responding to emergency incident handling, shall comply with the following provisi…
Supervision and Spectrum Resources监督检查与频谱资源 · 31 questions
- The amateur radio station licensee shall accept supervision and inspection of the amateur radio station and it…
- Which of the following statements about radio spectrum resources is correct? (Choose all that apply.)
- Which of the following statements about radio frequencies, services, and stations is correct? (Choose all that…
- "Whoever, in violation of state regulations, arbitrarily establishes or uses a radio station, or arbitrarily u…
- The use of radio frequencies must be approved by the radio management authority, based fundamentally on "radio…
- Radio control refers to the compulsory management, implemented in accordance with the law, of the emission, ra…
- Radio control refers to the management of which nature, implemented in accordance with the law within a specif…
- When radio control is implemented within a specific time period and area, the management measures related to a…
- The bodies that decide to implement radio control are: (Choose all that apply.)
- Those who violate radio-control orders and radio-control instructions shall be punished in accordance with the…
- An amateur station that violates radio-control orders and instructions may, in accordance with regulations, be…
- For using a radio frequency without authorization, the radio management authority may, according to the specif…
- For arbitrarily establishing or operating an amateur radio station, the radio management authority may, accord…
- Arbitrarily establishing or using a radio station to engage in fraudulent or other unlawful activities may, ac…
- For establishing or operating an amateur radio station not in accordance with the permitted matters and requir…
- For intentionally transmitting or receiving radio signals beyond the matters recorded in the amateur radio sta…
- For arbitrarily compiling or using an amateur radio station call sign, the radio management authority may, acc…
- Where an amateur station interferes with the normal conduct of radio services, the radio management authority …
- Where an amateur station causes harmful interference to radio frequencies involving personal safety, such as d…
- For researching, producing, selling, or repairing high-power radio transmitting equipment without taking effec…
- For overseas organizations or individuals conducting radio-parameter testing or radio monitoring within the te…
- For providing domestic radio-parameter data involving national security to overseas organizations or individua…
- For producing or importing radio transmitting equipment for sale or use within the country that has not obtain…
- For selling radio transmitting equipment that, under Article 44 of these Regulations, should have obtained typ…
- Regarding violations of the Radio Regulations of the People's Republic of China (《中华人民共和国无线电管理条例》), which of t…
- For concealing relevant circumstances, providing false materials, or making false commitments when applying fo…
- For obtaining an amateur radio station license by deceptive, bribing, or other improper means, the following p…
- In the Law on Public Security Administration Punishments of the People's Republic of China (《中华人民共和国治安管理处罚法》),…
- Regarding the Cybersecurity Law of the People's Republic of China (《中华人民共和国网络安全法》), which of the following sta…
- The National Security Law of the People's Republic of China (《中华人民共和国国家安全法》) states that national security wor…
- Which of the following are obligations that citizens and organizations shall perform as stipulated in the Nati…
Frequency Allocation and Emission频率划分与发射特性 · 50 questions
- When an amateur radio station transmits on a frequency where the amateur service or amateur-satellite service …
- The correct statement about the use of amateur frequencies is:
- In the Table of Frequency Allocations, when a band is allocated to the amateur service or amateur-satellite se…
- In the Table of Frequency Allocations, when a band is allocated to the amateur service or amateur-satellite se…
- The frequency bands allocated by our country exclusively to the amateur service and amateur-satellite service …
- The bands below 30 MHz that our country allocates for shared use between the amateur service (and amateur-sate…
- In the VHF and UHF range, our country allocates the amateur service (and amateur-satellite service) for shared…
- The number of bands our country allocates for shared use with other services where the amateur service is the …
- The bands below 1200 MHz that our country allocates for shared use where the amateur service is a secondary se…
- The highest frequency band allocated by our country to the amateur service and amateur-satellite service, and …
- The international amateur community colloquially calls the three HF bands added to the amateur (and amateur-sa…
- The so-called 40 m amateur band, its frequency ranges in ITU Regions 1, 2, and 3 and the amateur-service usage…
- The frequency range of the so-called 160 m amateur band and the amateur-service usage status are respectively:
- The frequency range of the so-called 80 m amateur band and the amateur-service usage status are respectively:
- The frequency range of the so-called 20 m amateur band and the amateur-service usage status are respectively:
- The frequency range of the so-called 15 m amateur band and the amateur-service usage status are respectively:
- The frequency range of the so-called 10 m amateur band and the amateur-service usage status are respectively:
- The frequency range of the so-called 6 m amateur band and the amateur-service usage status are respectively:
- The frequency range of the so-called 2 m amateur band and the amateur-service usage status in our country are …
- The frequency range of the so-called 0.7 m (70 cm) amateur band and the amateur-service usage status are respe…
- In the frequency allocation of our country and most others, the amateur service is a secondary service sharing…
- The band allocated by our country to the amateur service and amateur-satellite service that falls within the l…
- Short-wave amateur stations should avoid transmitting within ±500 Hz of the IARU beacon operating frequencies.…
- On the 7 MHz band, the frequency range a Chinese short-wave amateur station may actually occupy when conductin…
- On the 14 MHz band, the frequency range a short-wave amateur station may actually occupy when conducting USB v…
- On the 18 MHz band, the frequency range a short-wave amateur station may actually occupy when conducting USB v…
- On the 21 MHz band, the frequency range a short-wave amateur station may actually occupy when conducting USB v…
- On the 24 MHz band, the frequency range a short-wave amateur station may actually occupy when conducting USB v…
- On the ~29 MHz band, the frequency range a short-wave amateur station may actually occupy when conducting USB …
- On the ~29 MHz band, the frequency range a short-wave amateur station may actually occupy when conducting FM v…
- When conducting local contacts on the 144 MHz band, the frequencies a VHF amateur station should avoid occupyi…
- When conducting local contacts on the 430 MHz band, the frequencies a UHF amateur station should avoid occupyi…
- Where the lower frequency limit of a band allocated to the amateur service is F1, the actual transmit frequenc…
- Where the upper frequency limit of a band allocated to the amateur service is F2, the actual transmit frequenc…
- The ITU's attitude toward the 5–30 MHz short-wave bands is:
- The principle laid down by the International Telecommunication Union for determining the radiated power of a t…
- A club has arranged a net frequency for its members to exchange technical information. When another amateur st…
- The ITU Radio Regulations prohibit all stations from emitting the following kind of wave:
- Which of the following illegal acts will be handled by the radio management authority in accordance with the R…
- The principles for amateur stations using amateur-service frequencies are: (Choose all that apply.)
- The lowest band allocated by our country's Radio Frequency Allocation Regulations to the amateur service is 13…
- The 1,800 kHz–2,000 kHz allocated by our country's Radio Frequency Allocation Regulations to the amateur servi…
- The 28 MHz–29.7 MHz allocated by our country's Radio Frequency Allocation Regulations to the amateur service b…
- The 50 MHz–54 MHz allocated by our country's Radio Frequency Allocation Regulations to the amateur service bel…
- The band allocated by our country's Radio Frequency Allocation Regulations to the amateur service that is clos…
- The 430–440 MHz amateur band is closest to the operating frequencies of public walkie-talkies (citizen-band ra…
- The band allocated by our country's Radio Frequency Allocation Regulations to the amateur service that is clos…
- The band allocated by our country's Radio Frequency Allocation Regulations to the amateur service that is clos…
- The band allocated by our country's Radio Frequency Allocation Regulations to the amateur service that is clos…
- The highest band allocated by our country's Radio Frequency Allocation Regulations to the amateur service is 2…
International Radio Regions国际无线电区域划分 · 20 questions
- To divide radio frequencies worldwide, the International Telecommunication Union (ITU) Radio Regulations presc…
- In amateur radio administration we often use the method of dividing the globe into 3 radio-management Regions.…
- The ITU regional division has a detailed set of rules. In summary, it is roughly:
- Amateur frequency allocation differs slightly among the 3 ITU radio-management Regions. The 40 m amateur band …
- Voice contacts on the 2 m band are usually at 144.035–145.800 MHz, which is also a multi-mode shared sub-band …
- Voice contacts on the 2 m band are usually found in 144.035–145.800 MHz. This is also a multi-mode shared sub-…
- In the 70 cm band, amateurs often conduct voice communication in 438–440 MHz. This is also a multi-mode shared…
- In the 70 cm band, amateurs often conduct voice communication in 438–440 MHz. This is also a multi-mode shared…
- In the 10 m amateur band, the segment reserved for the amateur-satellite service, which voice and other commun…
- In the 144 MHz amateur band, the segment reserved for the amateur-satellite service, which voice and other com…
- In the 430 MHz amateur band, the segment reserved for the amateur-satellite service, which voice and other com…
- During a contact, what method lets you clearly convey the English letters in a call sign or important message?
- When a call sign, term, or necessary text must be spelled out, amateur radio operators generally use the spell…
- When a call sign, term, or necessary text must be spelled out, amateur radio operators generally use the spell…
- When a call sign, term, or necessary text must be spelled out, amateur radio operators generally use the spell…
- When a call sign, term, or necessary text must be spelled out, amateur radio operators generally use the spell…
- When a call sign, term, or necessary text must be spelled out, amateur radio operators generally use the spell…
- When a call sign, term, or necessary text must be spelled out, amateur radio operators generally use the spell…
- When a call sign, term, or necessary text must be spelled out, amateur radio operators generally use the spell…
- When a call sign, term, or necessary text must be spelled out, amateur radio operators generally use the spell…
CQ Calls and Initiating ContactsCQ 呼叫与发起联络 · 25 questions
- If an amateur station is calling CQ, what does it mean?
- How does an amateur station initiate a CQ call?
- How do you answer a CQ call?
- Operator Xiaoqiang wants to call another amateur station and speak with operator Xiaoming. The correct method …
- After an amateur station establishes communication, the necessary information the two sides should exchange fi…
- Why do amateur stations always exchange signal reports immediately after establishing communication?
- In modern amateur radio communication, signal reports all use the "RST format". In the abbreviation RST, the l…
- Xiaoming and Xiaoqiang make a CW and an FM contact; both receivers indicate a signal strength of "5". For the …
- An amateur station should listen before transmitting (monitor first). But sometimes, because you cannot hear o…
- BH1ZZZ wishes to join an ongoing contact between two other stations. The correct method is:
- If during a contact you hear a station in distress requesting to break in, what should you do?
- When requesting to break into a conversation between two stations, a worthwhile rule of thumb is:
- If you find that an amateur station's transmitting operating technique is not quite standard, but it is not ye…
- An amateur station's communication suffers serious interference from an illegal or unidentified station. The c…
- If you have a lot of important technical matters and personal news to exchange with an amateur station several…
- Regulations and international amateur radio practice require the following as the necessary contents of an ama…
- Exchanging QSL cards between amateur radio stations has multiple meanings, including: (Choose all that apply.)
- What contents should a QSL card at least cover? (Choose all that apply.)
- Regarding the use of QSL cards, which of the following statements is correct?
- When you receive a QSL card mailed from overseas and the envelope also contains one or more IRCs (Internationa…
- The correct way to fill in and mail a QSL card is:
- When exchanging QSL cards, we sometimes meet a special kind of radio enthusiast who only sends us a listening …
- When working through a repeater, we should preset the radio's receive/transmit offset in advance, so we can sm…
- If you call a specific amateur station through a repeater, you should:
- The principle for using an amateur repeater is:
Calling Procedure and Listening呼叫程序与守听 · 7 questions
- Before initiating a call, an amateur station should listen for a while and then ask "is anyone using the frequ…
- The method for amateur station BH1ZZZ to initiate a CQ call in FM or SSB voice is:
- The method for amateur station BH1ZZZ to initiate a CQ call in voice is:
- The method for amateur station BH1ZZZ to call BH8YYY in voice is:
- After establishing voice communication, operator Xiaoming wants to give the other station BH1ZZZ a signal repo…
- After establishing voice communication, Xiaoming wants to say he is operating from Chengdu. He can say:
- When listening to SSB contacts between amateur radio operators, we sometimes hear short phrases like "Cheerio.…
Q Codes and AbbreviationsQ 简语与常用缩语 · 82 questions
- During QRP operation, if the other station reports your signal is weak, you might ask whether you should incre…
- During a contact, if you believe QRP operation is enough to ensure reliable communication, you can negotiate w…
- When amateur stations conduct communication research or chase awards at power below 5 W, they often append the…
- During a contact, if you want the other station to increase its sending speed, you can send:
- During a contact, if the other station asks you to increase sending speed, you can confirm by asking back. You…
- During a contact, if you want the other station to reduce its sending speed, you can send:
- During a contact, if the other station asks you to reduce sending speed, you can confirm by asking back. You c…
- When ending the day's operating activity, an amateur station often sends the Q-code "QRT". Its meaning is:
- Before ending a contact, we may ask the other party whether there is any further message to convey. At this po…
- When ending a contact, we can tell the other party that there is nothing further here. At this point we may se…
- During a contact, if you wish to ask the other party to join in some amateur radio activity (e.g., "Mulan Weic…
- The meaning of the Q-code "QRV" is:
- When making a call, if you did not hear the other station's call sign clearly, you may use the following phras…
- The meaning of the Q-code "QRZ" is:
- Reading early Chinese amateur radio literature, we may encounter a signal report expressed with a Q-code and f…
- During a contact, if you want to find out whether your signal is fading, you may use the phrase:
- The meaning of the Q-code "QSB" is:
- Xiaoqiang and Xiaoming are practicing CW. If Xiaoqiang asks "Do I have a fault in my sending technique?", he c…
- Xiaoqiang and Xiaoming are practicing CW. Xiaoming thinks Xiaoqiang's technique was poor when sending the lett…
- Xiaoqiang and Xiaoming are practicing CW. Xiaoming thinks Xiaoqiang's sending has a thumping key-click sound. …
- The meaning of the Q-code "QSK" is:
- During a contact, if you need the other station to confirm that it received your message, you may use the phra…
- The meaning of the Q-code "QSL" is:
- The meaning of the Q-code "QSO" is:
- During a contact, if you want to find out whether the other station can help relay a message to "station xxx",…
- The meaning of the Q-code "QSP" is:
- During a contact, if Xiaoming wants Xiaoqiang to help listen out for his FT8 operation on 7074 kHz, he can sen…
- When Xiaoqiang tells Xiaoming that he is listening for FT8 contacts on 7074 kHz, he can send:
- During a contact, if you need to negotiate with the other party to change frequency to nnnn kHz (or MHz), you …
- The meaning of the Q-code "QSY" is:
- During a contact, if you want to know the other station's location, you may use the phrase:
- When ending the current contact and exchanging good wishes, amateur radio operators often use the abbreviation…
- If, during a CW or other text-mode contact, you must ask the other party for the mailing address for their QSL…
- If you need the other party to repeat the previous operation, such as re-sending the call sign or the signal r…
- The meaning of the amateur-radio abbreviation "AHR" is:
- The abbreviation for "amateur radio direction finding" is:
- When exchanging QSL information during a CW contact, we may use the term "post office box." Its abbreviation i…
- The abbreviation for "QSL card bureau (manager)" is:
- In a CW contact, we sometimes copy the abbreviation "CK", which means:
- The abbreviation an amateur station uses when making a general call is:
- When describing a signal coming from a distant place, amateurs often use the abbreviation:
- In a CW contact, we sometimes copy the abbreviation "ES", which means:
- In a CW contact, we sometimes copy the abbreviation "FB", which means:
- In a CW contact, we sometimes copy the abbreviation "FER", which means:
- The abbreviation for the term "frequency" is:
- After establishing a CW contact, we often greet the other party while exchanging signal reports. The abbreviat…
- After establishing a CW contact, we often greet the other party while exchanging signal reports. The abbreviat…
- When ending the current contact and wishing the other party good luck and good results, amateur radio operator…
- The meaning of the amateur-radio abbreviation "GLD" is:
- After establishing a CW contact, we often greet the other party while exchanging signal reports. The abbreviat…
- Sometimes, the DX station we contact still uses "GMT" to express time. The meaning of this time is:
- The meaning of the amateur-radio abbreviation "GN" is:
- The meaning of the amateur-radio abbreviation "GND" is:
- In late December each year, we often hear the abbreviation "HNY" in CW contacts, which means:
- In a CW contact, we sometimes copy the abbreviation "HPE", which means:
- In a CW contact, we sometimes copy the abbreviation "HPY" or "HPI", which means:
- The abbreviation for "high-speed telegraphy" is:
- When an amateur station finishes its current transmission and listens for any station, it should use the abbre…
- When an amateur station finishes its current transmission and listens only for the other station in the contac…
- To express "thank you very much" in a CW contact, we send:
- The meaning of the amateur-radio abbreviation "NW" is:
- During contacts, we sometimes call the other operator "old man." This likens the other party to a close comrad…
- The abbreviation for "operator" is:
- In daily CW (continuous wave) contacts, appropriately using imperative sentences that include the word "please…
- Similar to "QSL", if you have completely copied the message sent by the other station, we often start a new ex…
- In the amateur radio service, the meaning of "SAE" is:
- When amateur radio operators mail QSL cards, they often mention the abbreviation "SASE", whose meaning is:
- In a contact, if you need to correct content you just sent wrongly, you usually start the exchange with "sorry…
- The abbreviation for "temperature" (温度) is:
- The abbreviation for "thank you" (谢谢) is:
- The abbreviation for "thank you" (谢谢你, short) is:
- "Your" or "you are" can be expressed by the abbreviation:
- In CW contacts, we sometimes copy the abbreviation "WL", which means:
- Listening to CW or SSB contacts, we sometimes hear the abbreviation "XYL". Its meaning is:
- There is a class of amateur radio operators honored with the title "YL", and some amateur radio contests have …
- The term "element" (单元) usually refers to an antenna element (radiator). Its abbreviation is:
- When discussing antennas in amateur radio contacts, the abbreviation DP stands for:
- When discussing antennas in amateur radio contacts, the abbreviation GP stands for:
- When discussing antennas in amateur radio contacts, the abbreviation VER stands for:
- When discussing antennas in amateur radio contacts, the abbreviation LW stands for:
- When discussing antennas in amateur radio contacts, the abbreviation YAGI stands for:
- When discussing antennas in amateur radio contacts, the abbreviation BEAM stands for:
Emission Classes发射类别 · 23 questions
- "Class of emission" means a set of characteristics of an emission designated by standard symbols, e.g., the ma…
- "Class of emission" means a set of characteristics of an emission designated by standard symbols, e.g., the ma…
- "Class of emission" means a set of characteristics of an emission designated by standard symbols, e.g., the ma…
- "Class of emission" means a set of characteristics of an emission designated by standard symbols, e.g., the ma…
- "Class of emission" means a set of characteristics of an emission designated by standard symbols, e.g., the ma…
- "Class of emission" means a set of characteristics of an emission designated by standard symbols, e.g., the ma…
- Out-of-band emission means:
- In amateur radio communication the three most basic modulations are abbreviated AM, FM and PM. Their Chinese n…
- Which modulation is widely used for VHF or UHF local contacts?
- Which modulation is widely used for long-distance and weak-signal VHF or UHF voice contacts?
- Which modulation is widely used for HF voice contacts?
- What is the advantage of SSB compared with FM?
- What is the main disadvantage of FM compared with SSB?
- For SSB contacts on VHF and UHF bands, which sideband is usually selected?
- For voice communication on HF bands of 14 MHz and above, which sideband is usually selected?
- For voice communication on bands of 7 MHz and below, which sideband is usually selected?
- Why do amateur stations use lower sideband for voice below 10.1 MHz but upper sideband above 10.1 MHz?
- When initiating an SSB call, the frequency separation between you and nearby stations should be at least:
- Which of the following modulation modes can be classified under amplitude modulation (AM)?
- In the amateur radio service there is a communication mode abbreviated CW. Its meaning is:
- Which modulation mode has the narrowest emission bandwidth?
- Amateur stations generally do not use FM phone for Morse code contacts. This is because:
- Whether FM or SSB modulation, applying an audio signal 10 times the specified input voltage to the microphone …
Digital Communication Modes数字通信方式 · 5 questions
- Yaesu System Fusion, abbreviated YSF, is a communication mode integrating digital voice and data transmission.…
- The Icom D-STAR System provides a data communication mode, whose characteristics are: (Choose all that apply.)
- FreeDV is a digital voice mode. Its characteristics are: (Choose all that apply.)
- Digital amateur television (DATV) is a mode applying digital audio/video compression coding to real-time image…
- When using the DRM protocol for digital slow-scan television (DSSTV) communication, amateurs always tend to tr…
Transceivers and Receiver Systems收发信机与接收系统 · 54 questions
- What is a transceiver (收发信机)?
- What components does a working radio receiving system minimally contain? (Choose all that apply.)
- What components does a working radio transmitting system minimally contain? (Choose all that apply.)
- Why should the DC power cable used by an amateur transceiver be as short and as thick as possible?
- Simplex operation means a mode of operation in which transmission alternates in the two directions of a teleco…
- Duplex operation means a mode in which the two directions of a telecommunication channel can transmit simultan…
- Semi-duplex operation means a mode where one end of the circuit uses simplex and the other end uses duplex. Wh…
- What signal does PTT in a transceiver refer to?
- What function does the symbol SQL on the transceiver panel or in the setup menu represent?
- What is the purpose of setting the squelch function on a transceiver?
- When you need to listen for very weak FM signals, how should you set the transceiver's squelch?
- When receiving FM voice with a squelch-equipped FM transceiver, we sometimes hear a brief "hiss" or "crackle" …
- What function does the symbol VOL on the transceiver panel or in the setup menu represent?
- What function does the symbol VOX on the transceiver panel or in the setup menu represent?
- Since the transceiver already has PTT functionality, why do some models also provide VOX?
- Some handheld radios have the function of sending CTCSS codes. The abbreviation CTCSS refers to:
- Some handheld radios have the function of sending DTMF codes. The abbreviation DTMF refers to:
- Both sub-audible-tone and digital sub-audible-tone squelch techniques add a low-frequency signal that is hard …
- Some FM receivers have NFM and WFM options in the parameter setup menu. Their meanings are:
- In the setup menus of some VHF/UHF amateur FM handheld radios or mobile stations there are "full deviation" an…
- If the other station reports that your FM transmitter's signal sounds severely distorted with poor readability…
- If you need to quickly switch to a frequency you commonly use, how should you set up your radio?
- Where should the negative terminal of a mobile station's DC power supply be connected?
- Sometimes a mobile radio installed in a car may emit a sharp whine that varies with engine speed. Its source i…
- If another amateur station reports that your handheld radio's transmitted FM signal has excessive deviation, w…
- If another station reports that your transmission is interfering with adjacent-channel communication, what you…
- If another station reports that your signal on the 2-meter band was originally strong but suddenly became weak…
- If the surroundings are noisy during SSB or CW communication (QSO), which device can replace the radio's speak…
- Full-featured small transceivers often have functions abbreviated "NB" and "SQL" on the panel. What is the dif…
- Some vehicles' spark plugs radiate impulse interference. This may cause the receiver's AGC to act too early, s…
- What function does "MODE" on the panel of a full-featured small transceiver represent?
- What function does the symbol ATT on the transceiver panel represent?
- What function does the symbol AGC on the transceiver panel represent?
- Since full-featured receivers have AGC, why do many models also have an attenuator (ATT) switch?
- Regarding the receiver "overload" phenomenon, which of the following descriptions is correct? (Choose all that…
- The situation in which the receiver's AGC function should be turned off is:
- The situation in which a shorter AGC time constant should be selected is:
- The situation in which a longer AGC time constant should be selected is:
- On most small full-featured transceivers you can see the symbol PRE on the panel. What function does it repres…
- What function does the symbol ALC on the transceiver panel represent?
- In an SSB transmitter, what is the main function of transmit automatic level control (ALC)?
- When an amateur station conducts SSB voice communication, if the other party reports that although your speech…
- Even with the transmitter's ALC turned on, setting the microphone gain too high can still lead to:
- Why is it necessary to turn off ALC when sending AFSK signals with an SSB transceiver?
- What is the function of the speech compression feature in an SSB transmitter?
- What function does the symbol PROC on the transceiver panel represent?
- When transmitting, what problem may improper adjustment of speech compression cause?
- Why should the speech compression function be turned off when sending AFSK signals with an SSB transceiver?
- When an amateur station measures transmit power and antenna SWR by transmitting, what must be noted and done i…
- An SSB amateur station needs to transmit a steady continuous signal to test and check the antenna SWR. The cou…
- What function do the symbols AT or TUNE on the transceiver panel represent?
- When listening with a communications receiver that has separate RF/IF gain and audio gain controls, you can se…
- Compared with VHF or UHF communication, what is the biggest difference of HF communication?
- Which of the following methods can reduce the RF current that may be induced in the audio cable of a microphon…
Antenna Fundamentals天线的作用 · 70 questions
- The function of a transmitting antenna is:
- The function of a receiving antenna is:
- Regarding antenna gain, which of the following statements is correct? (Choose all that apply.)
- Antenna gain expressed in dBi means:
- What is an "ideal point-source antenna"? And what is its significance for amateur radio?
- Antenna gain expressed in dBd means:
- The half-wave dipole is a practical antenna capable of radiating radio waves. To obtain the lowest input imped…
- The antenna gain indicator given in a certain commercial antenna manual is expressed in dB. Its meaning is:
- The reason we call a vertical grounded antenna an "omnidirectional antenna" is:
- If a vertically grounded (ground-plane) antenna is required to have a main lobe at a horizontal launch angle o…
- Regarding the maximum-radiation direction of a vertically grounded (ground-plane) antenna whose element is 1/4…
- Which of the following statements about the "rubber-duck" antennas supplied with most handheld transceivers is…
- What problem may be encountered when using a handheld transceiver with a flexible "rubber-duck" antenna for co…
- If, when erecting an antenna, you find mains-powered equipment such as power lines near the site, what should …
- The vertically grounded antenna (GP) consists of a vertical element with an electrical length of 1/4 wavelengt…
- Which of the following descriptions about antenna loading is correct?
- The element of a resonant vertically grounded antenna must be at least 1/4 wavelength long. If site constraint…
- Antenna A has a gain of 6.15 dBi and antenna B has a gain of 1 dBd. If both antennas are erected under the sam…
- Antenna A has a gain of 0 dBd and antenna B has a gain of 2 dBi. If both are erected under the same conditions…
- Two VHF vertical omnidirectional antennas are used for transmitting. Antenna A has a gain of 4.5 dBd and anten…
- Two VHF vertical omnidirectional antennas are used for transmitting. Antenna A has a gain of 2.9 dBd and anten…
- When amateur radio operators discuss antenna systems they often mention the term "standing-wave ratio (SWR)". …
- During a contact, if the transceiver's SWR meter reads 4:1, this means:
- Xiaoqiang uses a 50 Ω feed line no shorter than 1/4 wavelength to connect the transceiver and antenna. While t…
- Most transmitters reduce output power when the SWR exceeds a certain value. This is in order to:
- When connecting an antenna with coaxial cable, why is it better for the SWR to approach 1:1?
- Which of the following situations may cause the SWR displayed by an amateur transmitter to be unstable?
- During SSB contacts, even when the antenna/feed system has no fault, the SWR reading is sometimes unstable. Th…
- We all know the feed line between transmitter and antenna should match the antenna impedance. Otherwise, stand…
- For amateur radio communication, the most suitable characteristic impedance of coaxial cable is:
- Transmission lines come in many types, but why is coaxial cable usually chosen when setting up an amateur stat…
- When purchasing coaxial cable for use as an antenna feed line for an amateur station, which electrical paramet…
- We all know to choose a low-loss feed line for the amateur station. But what problems can feed-line loss cause…
- Moisture ingress is a main cause of coaxial cable failure and damage. Moisture penetration can cause: (Choose …
- When installing coaxial cable outdoors, why is the cable jacket required to resist ultraviolet (UV) light?
- Compared with coaxial cable filled with organic dielectric, what is the disadvantage of air-dielectric coaxial…
- If the signal frequency passing through a coaxial cable rises, the coaxial cable's:
- Several feed lines of equal outer diameter are listed below. Which has lower loss in the VHF/UHF bands?
- For signals at 400 MHz or higher, the coaxial connector that should be preferred is:
- Which of the following statements about the Type M coaxial connector is correct?
- Which of the following statements about a vertical antenna is correct? (Choose all that apply.)
- Which of the following descriptions about a horizontally polarized dipole antenna is correct? (Choose all that…
- Stations A and B are 10 km apart, both using 1/2-wavelength horizontal dipole antennas for UHF communication. …
- Stations A and B are 10 km apart, using 1/2-wavelength horizontal and vertical dipole antennas respectively fo…
- Stations A and B are 10 km apart, using 1/2-wavelength horizontal and vertical dipoles respectively for UHF. N…
- Stations A and B are 10 km apart, using left-hand and right-hand circularly polarized antennas pointed at each…
- Stations A and B are 10 km apart, using left-hand and right-hand circularly polarized antennas pointed at each…
- Stations A and B are 10 km apart, using left-hand circular polarization (A) and a half-wave horizontal dipole …
- Stations A and B are 10 km apart, using left-hand circular polarization (A) and a half-wave horizontal dipole …
- Stations A and B are 10 km apart, using left-hand circular polarization (A) and a half-wave horizontal dipole …
- Stations A and B are 10 km apart, using left-hand circular polarization (A) and a half-wave horizontal dipole …
- Stations A and B are 10 km apart, using left-hand and right-hand circularly polarized antennas pointed at each…
- Assume both receiving and transmitting antennas use half-wave dipoles. For short-distance communication betwee…
- A right-hand polarized wave means, on any plane perpendicular to the direction of propagation, when viewed alo…
- In line-of-sight communication, given the transmitting antenna is a left-hand circularly polarized antenna poi…
- A satellite's downlink uses a right-hand circularly polarized antenna, flies from north to south, and the ante…
- It is known that a satellite's downlink transmitting antenna is a dipole pointing at the ground. Because the s…
- An amateur station using a half-wave vertical dipole for a contact receives an S4 signal strength at the other…
- An amateur station transmitting with a half-wave vertical dipole yields an S4 received signal at the other end…
- Two amateurs use half-wave vertical dipoles to contact each other; each receives the other's signal at S4. Now…
- Even on an open plain or vast desert, the strength of locally received VHF/UHF signals changes periodically as…
- A phenomenon in VHF/UHF contacts: if a distant station gives a poor signal report, merely moving a few steps o…
- The effect of multipath propagation on UHF or VHF data communication is:
- When using VSB (vestigial sideband) for ATV (amateur television) communication, even when the signal is relati…
- The main factor that determines the maximum range of ultra-short-wave (VHF/UHF) line-of-sight propagation is:
- Sometimes amateur stations hundreds of kilometres apart can make VHF/UHF beyond-line-of-sight direct contacts.…
- Sometimes we can receive "beyond-line-of-sight propagation" signals from over a thousand kilometres away on th…
- What causes tropospheric atmospheric ducting?
- If you receive a VHF signal from over a thousand kilometres away, the most likely reason is:
- Sometimes "beyond-line-of-sight propagation" signals up to 500 km away may appear in VHF/UHF amateur bands. Th…
Transmitters and Modulation发射机与调制 · 62 questions
- When testing a self-made amateur radio transmitting device, before it passes inspection by a radio testing org…
- In a radio transmitter, the role of the modulator is:
- The main factors that ensure good receiving capability of an amateur radio communication receiver are: (Choose…
- The role of a receiver's demodulator is:
- The main factor to consider when selecting a demodulator is:
- In the sub-audible tone squelch system (CTCSS), roughly what range within the audio band do the tones occupy?
- For a more refined receiver, its specification sheet often lists a "passband rectangular coefficient" or "pass…
- According to the technical specifications, two amateur radio receivers have different "passband rectangular co…
- The main role of a receiver preamplifier is:
- During FM voice communication, can we accurately judge how strong the other station's signal is solely from ho…
- The effect of receiving a WFM signal with a handheld transceiver set to NFM mode is:
- The effect of receiving an NFM signal with a handheld transceiver set to WFM mode is:
- When there is no signal, an FM receiver outputs a strong "shhh" noise. Regarding this noise, the correct descr…
- Which of the following circuits can demodulate an FM signal?
- What is "discrimination" (frequency discrimination, 鉴频)?
- Which of the following can demodulate an AM signal?
- What is "detection" (检波)?
- Regarding the AGC function of a transceiver, the correct statements are: (Choose all that apply.)
- When studying modern communication technology or building amateur radio projects, we often encounter a "DC rec…
- What is the role of the mixer commonly found in receivers and transmitters?
- In a superheterodyne transceiver, the mixer's operation can be divided into "up-conversion" and "down-conversi…
- Superheterodyne amateur transceivers often have a control on the panel for selecting the IF filter bandwidth. …
- In a superheterodyne amateur transceiver, the component responsible for suppressing image-frequency interferen…
- In a superheterodyne receiver the received signal frequency is lower (or higher) than the local-oscillator fre…
- In a superheterodyne receiver the received signal frequency is lower (or higher) than the local-oscillator fre…
- In a superheterodyne receiver the received signal frequency is lower (or higher) than the local-oscillator fre…
- In a superheterodyne receiver the received signal frequency is lower (or higher) than the local-oscillator fre…
- The efficiency of an amateur radio transmitter means:
- The efficiency of an amateur radio transmitter is always significantly below 1. The lost portion of energy:
- If an amateur radio station operates at a DC voltage of 13.8 V, with an FM RF output power of N watts and a po…
- If an amateur radio station operates at an AC voltage of 220 V, with an FM RF output power of N watts and a po…
- If an amateur radio station transmits FM at an RF output power of N watts with a power-supply efficiency of ab…
- The average power supplied to the antenna feeder by a radio transmitter over one RF cycle under no-modulation …
- If a voice transmitter has the same peak output power under different modulation modes, then with no voice inp…
- Which of the following technical indicators describes a receiver's ability to reject adjacent-frequency interf…
- A receiver's ability to reject interference signals near its operating frequency can be expressed by selectivi…
- The flatness of a receiver's frequency response when receiving SSB voice signals can be expressed by selectivi…
- A receiver's ability to reject strong interference signals far from its operating frequency can be expressed b…
- A receiver's ability to reject strong interference signals at a frequency twice the IF away from its operating…
- What is the significance of the magnitude of a receiver's sensitivity indicator?
- What is the significance of expressing a receiver's sensitivity in terms of power level, and what are the comm…
- What is the significance of expressing a receiver's sensitivity in terms of voltage level, and what are the co…
- Most amateur radio receivers have a signal-strength indication function. In the VHF/UHF bands, the minimum sca…
- Two models of amateur transceivers, A and B, give receiver sensitivity indicators of 0.1 μV and 0.15 μV respec…
- When the output signal meets the specified quality standard, the minimum input-signal voltage measured at the …
- When the output signal meets the specified quality standard, the minimum input-signal voltage measured at the …
- When the output signal meets the specified quality standard, the minimum input-signal voltage measured at the …
- When the output signal meets the specified quality standard, the minimum input-signal voltage measured at the …
- When the output signal meets the specified quality standard, the minimum input-signal voltage measured at the …
- When the output signal meets the specified quality standard, the minimum input-signal voltage measured at the …
- Given a receiver whose antenna input impedance is 50 Ω and whose sensitivity specification is 2 μV, the corres…
- Given a receiver whose antenna input impedance is 50 Ω and whose sensitivity specification is 1 μV, the corres…
- The main factor limiting the sensitivity of a modern radio receiver is:
- The term "signal-to-noise ratio (SNR)" is widely used in amateur radio. It refers to:
- For amateur communication that must receive very weak signals, such as EME contacts, the receiver noise figure…
- The squelch sensitivity of a receiver is:
- For amateur communication that must receive very weak signals, such as EME contacts, the receiver noise figure…
- For amateur communication that must receive very weak signals, such as EME contacts, the receiver noise figure…
- For amateur communication that must receive very weak signals, such as EME contacts, the receiver noise figure…
- In radio communication, the "noise temperature" indicator is often used to describe the internal-noise magnitu…
- For an ideal amplifier or receiver that produces no internal noise, the noise figure Fn, noise figure NF, and …
- Suppose an antenna amplifier used for the amateur-satellite service operates at standard temperature (17 °C), …
Amateur Radio Satellites业余无线电卫星 · 8 questions
- In the amateur radio field, the abbreviation AMSAT refers to:
- When describing amateur radio satellites, the abbreviation OSCAR (奥斯卡) is often used. The origin of this name …
- The launch year, name, international OSCAR number, and transponder mode of China's first amateur satellite are…
- The best time to conduct EME (Earth-Moon-Earth / moonbounce) communication experiments is:
- When installing a preamplifier for occasions requiring reception of extremely weak signals, such as EME commun…
- For communication scenarios needing reception of VHF/UHF weak signals, such as moonbounce experiments, amateur…
- Which of the following amateur bands is most suitable for meteor-scatter communication?
- Which of the following communication modes can be used for meteor-scatter and tropospheric-scatter communicati…
Conductors and Current导体与电流 · 59 questions
- A conductor is a substance or material that readily conducts electric current. Which of the following descript…
- Regarding conductors, which of the following statements is correct? (Choose all that apply.)
- An insulator is a substance or material that does not readily conduct electric current. Which of the following…
- Which of the following can be used as insulating materials? (Choose all that apply.)
- "Breakdown" refers to a phenomenon where, when the voltage applied to an insulating medium exceeds a certain v…
- After the RF components in amateur radio equipment accumulate dust or become damp, even without breakdown or l…
- A semiconductor is a class of substance or material whose conducting ability lies between that of conductors a…
- Which of the following devices are made of semiconductor material? (Choose all that apply.)
- Electrostatic discharge (ESD) is a common electromagnetic phenomenon that accompanies daily life at all times.…
- If a conductor is placed in an electrostatic field, the conductor will exhibit the following characteristics: …
- Direct current (DC) is defined by the direction of charge motion never changing. Which of the following descri…
- Alternating current (AC) is defined by the direction of charge motion alternating with time. Which of the foll…
- Which of the following terms can be used to describe the number of times per second that alternating current c…
- What is the relationship between the "wavelength" frequently mentioned by amateur radio operators and the freq…
- The physical quantity "electromotive force (EMF)" describes:
- The physical quantity "voltage" describes:
- The peak value of a sinusoidal AC voltage or current refers to: ("x＾m" means "x to the power m")
- The peak-to-peak value of a sinusoidal AC voltage or current refers to:
- The RMS (root-mean-square) voltage of any AC voltage refers to: ("x＾m" means "x to the power m")
- The physical quantity "current" describes:
- The physical quantity "resistance" describes:
- The physical quantity "power" describes:
- Ohm's law for DC circuits states: (Choose all that apply.)
- The kinds of current that are not impeded by resistance in a circuit are:
- The term "impedance" describes:
- The unit of electromotive force is:
- The unit of voltage is:
- The unit of current is:
- The unit of resistance is:
- The unit of impedance is:
- The unit of power is:
- The unit of frequency is:
- In the legal system of units, the prefix k has the following mathematical meaning and verbal meaning respectiv…
- In the legal system of units, the prefix m has the following mathematical meaning and verbal meaning respectiv…
- In the system of legal units of measurement, what are the mathematical significance and textual meaning of the…
- In the system of legal units of measurement, what are the mathematical significance and textual meaning of the…
- In the system of legal units of measurement, what are the mathematical significance and textual meaning of the…
- In the system of legal units of measurement, what are the mathematical significance and textual meaning of the…
- In the system of legal units of measurement, what are the mathematical significance and textual meaning of the…
- In the system of legal units of measurement, what are the mathematical significance and textual meaning of the…
- Which of the following amateur radio abbreviations can express the term "radio frequency" or specifically refe…
- The term "audio frequency" (音频) refers to the frequency of sounds that people can generally hear. Which of the…
- The commonly used nominal impedances of the transmission interfaces for radio communication and related test e…
- 1,805,000 Hz can be expressed as:
- 2430 MHz can be expressed as:
- A resistor of 1 ohm resistance is connected in parallel with a 13.8-volt power source; the power dissipated by…
- 5 W can be expressed as:
- 0.25 W can be expressed as:
- 0.4 kW can be expressed as:
- A power source is a kind of power-supply device commonly used by amateur radio operators. Our understanding of…
- The direction of the electromotive force (EMF, 电动势) across the two terminals of a power source is:
- The direction of the voltage across the two terminals of a power source is:
- External power sources for supplying amateur radio equipment come in several types. Common ones include: (Choo…
- Which of the following batteries can be recharged? (Choose all that apply.)
- How can a 12-volt lead-acid battery be charged when the mains power is out?
- When using a storage battery to power a radio station, how should the battery operating time be estimated?
- The effect of a power source's internal resistance on a circuit is:
- Some transceivers have a fuse in series in the 13.8 V DC supply line, followed by a diode of very high rated c…
- Some transceivers have a reset button marked with a number near the 13.8 V DC power socket. What is its functi…
Measurement and Instruments测量与仪表 · 8 questions
- A multimeter's DC voltage range is used to measure a bipolar symmetric square-wave voltage (duty cycle 1:1). T…
- If a moving-coil (magneto-electric) multimeter's AC voltage range is used to measure a bipolar symmetric squar…
- Using an analog (pointer) multimeter's DC voltage range to measure a square-wave voltage whose minimum value i…
- A multimeter's resistance range is used to measure a circuit. At first the meter indicates a very small resist…
- To check whether an electrolytic capacitor is sound, one should use: (Choose all that apply.)
- Using an analog multimeter's resistance range to measure a common component, the first time the test leads are…
- An analog multimeter's voltage range has an "ohms-per-volt" (ohms per volt) specification. A larger ohms-per-v…
- Using a digital multimeter's DC voltage range to measure the voltage of a constant-amplitude audio signal betw…
Transmitter Technical Specs发射设备技术指标 · 31 questions
- The following indicators of amateur radio transmitting equipment must comply with relevant national regulation…
- The radio transmitting equipment of an amateur station should meet the following principal technical indicator…
- Frequency tolerance (频率容限) means: (Choose all that apply.)
- Frequency tolerance is an important indicator of transmitting equipment, and is usually expressed in the follo…
- Spurious-domain emission power is an important indicator of transmitting equipment, and is usually expressed i…
- Spurious emission (杂散发射) means: (Choose all that apply.)
- The principal technical-indicator requirements that dedicated amateur radio transmitting equipment must satisf…
- Which of the following situations produces damped-wave (减幅波) radiation:
- According to the national standard GB 8702-2014 'Electromagnetic Environment Control Limits' (《电磁环境控制限值》), fro…
- According to the national standard GB 8702-2014 'Electromagnetic Environment Control Limits' (《电磁环境控制限值》), pub…
- Why do the exposure limits in China's 'Electromagnetic Environment Control Limits' (《电磁环境控制限值》) standard diffe…
- Regarding self-made, modified, or assembled radio transmitting equipment, which of the following statements is…
- Do VHF and UHF signals in the air belong to which of the following types of radiation?
- Installing lightning protection for an amateur station is to prevent lightning damage. The main components of …
- The function of lightning-protection grounding is:
- Regarding the grounding of a lightning protection installation, the most basic requirement is:
- For an ordinary building, how large at most can the protection zone of a single lightning rod be:
- Which of the following conductive materials is most suitable for connecting the various grounded components at…
- What should be noted when installing a lightning arrester for a coaxial feed line?
- Which of the following is an effective measure for lightning-protection grounding of an antenna tower?
- Considering that the actual working environment necessarily has some humidity, then according to the limits fo…
- If the contact voltage is the same, how does the safety threat to the human body from touching a bare conducto…
- If you touch with both hands the two endpoints of circuits whose voltage effective values are the same but who…
- If it is unavoidable and you must repair live radio equipment powered by the mains, you should:
- A live equipment chassis can endanger personal safety. The relevant preventive measures include: (Choose all t…
- Even after the equipment's power cord has been unplugged, what safety risk may still be encountered during rep…
- For self-made equipment powered by 220 V AC mains, the safety measures should at least include:
- How can you ensure a self-made amateur radio project has high electrical safety? (Choose all that apply.)
- What potential risk exists when using an ordinary 12 V lead-acid battery to power the station?
- If a lead-acid battery is charged or discharged too fast, what risk arises?
- If electrical equipment, cables, or a power device catches fire, the correct action is:
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