CRAC Class B (2025) — Questions 171–180
U0176. The so-called 40 m amateur band, its frequency ranges in ITU Regions 1, 2, and 3 and the amateur-service usage status, are respectively:
俗称的40米业余波段，其在ITU1、2、3区的频率范围以及业余 业务和卫星业余业务的使用状态分别为：
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The 40 m band is 7.0–7.2 MHz in Region 1, 7.0–7.3 MHz in Region 2, and 7.0–7.2 MHz in Region 3 (China), and it is an exclusive (专用) amateur allocation (A). Options B/C/D misstate one or more region's edges.
U0177. The frequency range of the so-called 160 m amateur band and the amateur-service usage status are respectively:
俗称的160米业余波段的频率范围以及业余业务和卫星业余业务 的使用状态分别为：
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The 160 m band is 1800–2000 kHz and amateur is a primary service (主要业务) there (A). The other options give wrong edges or wrong service category.
U0178. The frequency range of the so-called 80 m amateur band and the amateur-service usage status are respectively:
俗称的80米业余波段的频率范围以及业余业务和卫星业余业务 的使用状态分别为：
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The 80 m band is 3.5–3.9 MHz and amateur is a primary service (主 要业务) there (A). Other options give wrong service category or wrong upper edge (4.0 MHz is Region 2).
U0179. The frequency range of the so-called 20 m amateur band and the amateur-service usage status are respectively:
俗称的20米业余波段的频率范围以及业余业务和卫星业余业务 的使用状态分别为：
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The 20 m band in China is 14–14.25 MHz exclusive (专用) and 14.25–14.35 MHz primary service (主要业务) (A). The other options misstate the split point or the upper edge.
U0180. The frequency range of the so-called 15 m amateur band and the amateur-service usage status are respectively:
俗称的15米业余波段的频率范围以及业余业务和卫星业余业务 的使用状态分别为：
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The 15 m band is 21–21.45 MHz and is an exclusive (专用) amateur allocation (A). The other options use the right edges with the wrong service category.
U0181. The frequency range of the so-called 10 m amateur band and the amateur-service usage status are respectively:
俗称的10米业余波段的频率范围以及业余业务和卫星业余业务 的使用状态分别为：
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The 10 m band is 28–29.7 MHz and is an exclusive (专用) amateur allocation (A). The other options change the upper edge or the category.
U0182. The frequency range of the so-called 6 m amateur band and the amateur-service usage status are respectively:
俗称的6米业余波段的频率范围以及业余业务和卫星业余业务的 使用状态分别为：
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The 6 m band is 50–54 MHz and amateur is a primary service (主要 业务) there (A). The other options give wrong edges or category.
U0183. The frequency range of the so-called 2 m amateur band and the amateur-service usage status in our country are respectively:
俗称的2米业余波段的频率范围以及我国业余业务和卫星业余业 务的使用状态分别为：
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In China the 2 m band is 144–148 MHz: 144–146 MHz is sole primary (唯一主要业务), and 146–148 MHz is shared-primary with other services (A). B is too narrow; C/D misstate the 146–148 MHz category.
U0184. The frequency range of the so-called 0.7 m (70 cm) amateur band and the amateur-service usage status are respectively:
俗称的0.7米业余波段的频率范围以及业余业务和卫星业余业务 的使用状态分别为：
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The 70 cm band in China is 430–440 MHz and amateur is a secondary service (次要业务) there (A). The other options change the category or widen the edges.
U0185. In the frequency allocation of our country and most others, the amateur service is a secondary service sharing the 430–440 MHz band with other services. The primary service allocated in this band in our country is:
在我国和多数其他国家的频率分配中，业余业务在430- 440MHz频段中作为次要业务与其他业务共用。这个频段中我 国分配的主要业务是：
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In the 430–440 MHz band, China's primary services are 无线电定位 (radiolocation) and 航空无线电导航 (aeronautical radionavigation) (A). Amateur is secondary, so it must avoid interfering with these primary users.