————Two hours from entry to burial

Recently entered HAM by Amway（ [informal] Amateur Radio). In fact, the concept of amateur radio is very broad. In China, except for the 20 409 MHz frequency points of public interphones, the rest are basically primary or secondary services. Here, the words corresponding to amateur (non professional) should be business, which does not mean the operating level of amateur radio operators.

As the saying goes, "Know yourself and your enemy, and you will never be defeated in a hundred wars." As a mainland student, examinations are our "skill". There are 374 questions in the question bank of Class A amateur radio station operation certificate. According to the official information, we can check:

The design of this question bank is based on the characteristics of computer random selection of questions. Therefore, some adjacent questions are actually the same examination site, but the specific question methods or specific data used are different, so the number of knowledge items that must be mastered is actually less than the number of questions in the overall database. For example, the A-class amateur radio operation certificate test paper involves about 370 questions, but the actual test points are about 250.

In other words, we actually need to remember about 250 knowledge points, And these questions are all single choice questions 。 Looking up the examination syllabus, we can know that the examination site is divided into the following five parts:

• Radio related laws and regulations
• Radio communication procedures and methods
• Principles of radio system
• Security Protection Technology of Amateur Radio Station
• Electromagnetic Compatibility Technology and Prevention and Elimination of Radio Frequency Interference

Laws, regulations and system principles account for the vast majority of the examination content, followed by communication procedures and methods. In addition to the policy questions, the content is basically based on the general knowledge of physics. With the basic knowledge of junior high school physics, you can quickly understand most of the content. I got 18 points when I used the simulation test program without any review. Even if you really can't remember the formula, we can still "fish in troubled waters" by backing options The overall review time is about 2 hours. The author passed the exam with 28 correct results, including a wrong question on the answer card (What a shame) 。 A total of 30 questions were drawn from the exam, and more than 25 correct questions are considered as passed, so it is more than enough to review the exam one night before.

Note: This is not a set of amateur radio textbooks, but an outline for the corresponding exam.

Shorthand of policy questions

After so many years of political problems, in fact, most situations can be confused. According to experience summary, we can draw the following conclusion: "Three short and one long selection is the longest, three games and one short selection is the shortest, special notes on special topics" 。 Most of the questions, obviously the longest and obviously the shortest, are the correct answers. When you look at the question bank, you can Highlight the correct option and the length comparison between this option and other options ， Don't need a word To remember details.

Then let's look at the special content:

• The central (national) departments are larger than the local departments, and the Central Military Commission, the State Council and the Ministry of Industry and Information Technology should also "get involved" in radio management.

For example, the conditions for applying for the establishment of amateur radio stations include: being familiar with radio management regulations Possess the operation and technical ability specified by the state Transmitting equipment shall meet other requirements specified in national technical standards, laws and administrative regulations.

• Amateur radio has nothing to do with sports, so there is no matter about sports related management organizations.

For example, the certification documents of various amateur radio station operation technical ability newly obtained after January 1, 2013 are: China Radio Association Amateur Radio Operation Certificate issued

• Amateur radio stations can only be used for technical research and popularization activities, and can not be used for any profit making purpose, nor can they forward radio stations, Internet chat, telephone calls and other content. The work designated by the relevant departments can only be accepted under the conditions of major sudden natural disasters.
• Radio control: specific time and specific area
• Class A: 25W, 30~3000 MHz, the transmission frequency cannot exceed amateur business, which is classified by the Regulations of the People's Republic of China on Radio Frequency Division.

For example, the main technical index requirements that must be met by amateur radio special transmitting equipment include: frequency tolerance and stray radiation Not exceeding the limit ， The transmission frequency shall not exceed the national amateur frequency

• To set amateur radio stations, you need to submit Two forms 。 Multiple devices use the same call sign. Renewal one month before the expiry date. All changes shall be handled in time.
• Relay station, beacon station, space station It belongs to special radio station
• A fine of 5000 yuan will be imposed for using black radio stations, and 30000 yuan will be imposed for falsifying certificates and exceeding the frequency regulations (balabala causing harm). (All are the most)
• Confused topics:

1. In radio management, a specific frequency band is listed in the frequency by the state divide Table, which stipulates that the frequency band can be used for amateur business or satellite amateur business under specified conditions. This process is called division
2. In radio management, set the radio frequency or channel regulations One or more departments provide ground or space radio communication services in designated areas under designated conditions. This process is called allocation
3. In radio management, set the radio frequency or channel approval The process of using specific amateur radio stations under specified conditions is called assignment

• Illegal acts must be prohibited, and harmful interference to other radio stations must be avoided.

Shorthand for common sense questions

In this chapter, please directly select the longest or shortest option for the explanation of some technical terms (such as multi-path propagation) and some common radio knowledge (how to call another station on the trunk).

• When operating the radio station in a different place/guest seat, the call sign should be added B+code of operation site+/ 。 When you are a guest radio station (guest transmission operation), you can also directly use the call sign of the other station (you don't need to memorize the code of the operation place, just select / )
• Abbreviations and abbreviations recognized in the field of plain language and amateur radio should be used at all times (low voice: it is impossible to judge whether it is recognized by the public or not)

Q: When 144MHz or 430MHz amateur analog FM repeater is selected, the principle of receiving and transmitting frequency difference in the same frequency band is?

A: Amateur radio standard frequency difference is adopted, i.e. 144MHz band 600kHz, 430MHz band 5MHz

• The other three items in the above question are text descriptions, so you don't need to remember them, just select the option with numbers.
• When you need to call others on the trunk, you need to call the other party's call sign and report your own call sign. CQ calls all stations extensively. To answer a CQ call, you need to report the other party's call sign first, and then your own call sign.
• Amateur repeaters should be equal and provide services to all amateur radio stations free of charge. And special person shall be on duty, equipped with remote control device, and can be shut down with one button if necessary.
• When the other party urgently needs to send back QSL (I always print SQL) cards, they should send the cards directly and attach SASE 。 If it is not used as communication or listening proof, it shall be attached Eye ball QSO 。 That QSO looks familiar, and this is the only correct choice question.
• It must be recorded in the log Communication mode (MODE) , directly select the option containing the communication mode.
• HF：3～30 MHz，VFH 30～300 MHz，UHF 300～3000MHz。
• Section U does not occupy 435~438MHz, Segment V does not occupy 145.8~146MHz.
• 50 ～ 54 MHz and 146 ～ 148 MHz are the main services. 430~440MHz is the secondary service.
• Any amateur radio station has equal access to frequency.
• Listen to the call before sending it, and use the idle frequency when testing the equipment.
• Whether the frequency is occupied, the error is: Calling you, Roger? 。
• "Does anyone use frequency" is QRL. "Who is calling me?" is QRZ. When encountering interference from other stations, it is QRM (Man), and when encountering interference from Tiandian, it is QRN (Natural). "QSL Card Received" is QSL, and "My Radio Location" is QTH (There). As for the reason why these letters are used, I didn't go into it. Anyway, I automatically added the words in parentheses.
• The correct information must be sent to each other to report the call sign and signal of both parties.
• Antenna is referred to as ANT, and amateur radio direction finding is referred to as ARDF. The old friend is called OM for short, and the radio equipment is called RIG for short. The transceiver is XCVR. 73 For "good wishes", Roger is used when reading the other party's message completely.
• DP is dipole antenna, G P is vertical Grounding Antenna. BEAM is a directional antenna, YAGI is Yagi antenna. VER is a vertical antenna. RF is called radio for short.
• There are 27 CQ partitions in China, There are 50 in ITU partition. Select the one with these two numbers.
• Maidenhead grid positioning system. I still can't remember the name of such a long string of horses. You only need to know that it is related to the longitude and latitude network, and select the one related to longitude and latitude. Please choose the longest format question directly.
• As for the abbreviations of those physical quantity units, you know more about CS and EE than I do. Just take a general look.
• The microwave oven is UHF.
• The receiving system shall have an output component and the transmitting system shall have a transmitting antenna.
• The average voltage of sinusoidal alternating current is 0, the effective voltage of sinusoidal alternating current with peak peak 100V is 35.4V, and the effective voltage of sinusoidal alternating current with peak 100V is 70.7V.
• WFM listens to the low sound of NFM, NFM listens to WFM distortion.
• Voice call needs about 6.25kHz
• The conversion formulas of those dBm dB μ are too troublesome to remember, remember 37、54、86 For these three numbers, select the option with these three numbers 。
• DBd is related to "half wave oscillator", DBi is related to "ideal point source". (Don't ask why)
• For the question of power difference, directly select the one whose answer is 0.8.
• The coaxial cable impedance is 50 Ω, and the N-type connector is used above 400 Mhz. The standing wave ratio of antenna and feeder is 1:1.
• The radio wave is 0.95 times of vacuum in the antenna wire and 0.65 times in the coaxial cable.
• Safety extra low voltage is 24V
• The lethal risk of DC is lower than that of AC.
• The protection range of the lightning rod is the top point of the lightning rod forty-five The space inside the cone.