CRAC Class B (2025) — Questions 191–200
U0196. When conducting local contacts on the 430 MHz band, the frequencies a UHF amateur station should avoid occupying are:
UHF业余无线电台在430MHz频段进行本地联络时应避免占用 的频率为：
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For local 70 cm work you should avoid 431.9–432.240 MHz (satellite uplink) and 435–438 MHz (satellite downlink) (A). The other options list the usable regions or wrong segments.
U0197. Where the lower frequency limit of a band allocated to the amateur service is F1, the actual transmit frequency an amateur station may operate at should be:
分配给业余业务的某频段的频率下限为F1，业余电台实际可以 工作的发信频率应为：
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For a band with lower edge F1, the transmit carrier must sit at F1 plus the lower-sideband width so the signal's lower edge stays at/above F1 (A). Placing the carrier at F1 (B) or below (C/D) would push the lower sideband below the band edge.
U0198. Where the upper frequency limit of a band allocated to the amateur service is F2, the actual transmit frequency an amateur station may operate at should be:
分配给业余业务的某频段的频率上限为F2，业余电台实际可以 工作的发信频率应为：
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For a band with upper edge F2, the carrier must sit at F2 minus the upper-sideband width so the signal's upper edge stays at/below F2 (A). Placing the carrier at F2 (B) or above (C) would push the upper sideband above the band edge.
U0199. The ITU's attitude toward the 5–30 MHz short-wave bands is:
ITU对于5至30MHz短波频段的态度是：
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The ITU Radio Regulations note that the 5–30 MHz bands are particularly suited to long-distance communication and encourage administrations, where practicable, to use other means of communication to avoid harmful interference to that long-distance service (A). B/C/D invert or contradict this policy.
U0200. The principle laid down by the International Telecommunication Union for determining the radiated power of a transmitting station is:
国际电联规定的确定发射电台辐射功率的原则为：
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The ITU principle (Radio Regulations, No. 21.1) is that a station should radiate only the minimum power necessary to give a satisfactory service (A). The other options promote maximum power, which is contrary to interference minimization.
U0201. A club has arranged a net frequency for its members to exchange technical information. When another amateur station, following normal operating practice, requests to join the communication, the principle of handling it should be:
某俱乐部约定了一个成员业余电台之间交流技术的网络频率， 当遇有其他业余电台按通信惯例要求参加通信时，处理原则应 为：
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All amateur stations have equal rights to amateur frequencies; a club cannot claim an exclusive "private" frequency, so any station requesting to join must be welcomed (A). B/C/D attempt to grant the club priority or exclusivity, which violates equal-access principle.
U0202. The ITU Radio Regulations prohibit all stations from emitting the following kind of wave:
ITU《无线电规则》禁止所有电台发射下列种类的电波：
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The ITU Radio Regulations prohibit the emission of damped waves (阻尼波) by all stations (A). AM, FM, and PM are all authorized emission types (B/C/D are permitted).
U0203. Which of the following illegal acts will be handled by the radio management authority in accordance with the Radio Regulations of the PRC? (Choose all that apply.)
下列哪些违法行为将由无线电管理机构依照《中华人民共和国 无线电管理条例》的规定处理：
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All four are unlawful acts handled under the Radio Regulations of the PRC (《中华人民共和国无线电管理条例》): (A) illegal interference with radio services; (B) leaking national-security radio data abroad; (C) unauthorized devising/use of call signs; (D) transmitting/receiving outside license particulars or misusing inadvertently received information. Each violates the regulation's prohibitions.
U0204. The principles for amateur stations using amateur-service frequencies are: (Choose all that apply.)
业余无线电台使用业余业务频率使用原则：
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When using amateur-service frequencies, an amateur station needs no radio-frequency use license and is exempt from frequency occupancy fees (A, B). C and D are the opposite of the preferential treatment granted to amateur radio.
U0205. The lowest band allocated by our country's Radio Frequency Allocation Regulations to the amateur service is 135.7–137.8 kHz; this belongs to the following radio-spectrum band (waveband):
我国《无线电频率划分规定》划分给业余业务使用的最低频段 为135.7-137.8kHz，属于无线电频谱的下列频段（波段）：
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135.7–137.8 kHz lies in the low-frequency (低频/LF, also called 长波 long wave) band, 30–300 kHz (A). VLF is 3–30 kHz, so B is wrong; C/D are not standard amateur-designated bands here.