CRAC Class C (2025) — Questions 471–480

In contest CW, "TEST" identifies contest operation and "UP 5" means the station is listening 5 kHz above its transmit (send) frequency (a split). B/C/D misread "UP 5" as a model number or a prefix.

When answering a CQ you transmit on the station's listening (receive) frequency, sending only your own full call so it can copy you; the running station already knows its own call, so repeating it (B/C) is unnecessary, and sending on its transmit frequency (D) collides with it.

In CQ WW, the single-operator unassisted category (SOAB — single operator, all band) must not use any spotting assistance such as CW Skimmer. The assisted category (SOAB-A) explicitly may; multi-single (MS) and single-band (SOSB-20) have their own allowances. Per the key, SOAB is the prohibited one.

In the IARU HF Championship, HQ (Headquarters) stations send an RSQ-style report ending in a society code; "JARL" identifies the Japan Amateur Radio League. The Japanese HQ station uses the special call 8N1HQ (the "8N1" series denotes Japanese special-event/HQ stations). The keyed answer is 8N1HQ.

In the IARU HF Championship the exchange is an RSQ-style report: the first two digits are the RS report (readability 5, strength 9) and the last two form the serial number of the contact sent. A valid report such as 5944 (59 + serial 44) is acceptable. Per the official key, 5944 is the correct choice.

The ALL ASIAN DX Contest exchange is an RS report plus the operator's age (two digits). A 20-year-old would send 59 + 20 = 5920 (B). The official key also accepts 5900 (A), where 00 is used when age is not disclosed. Options C (5944) and D (5924) encode ages 44/24 that do not match the operator, so they are not correct for her.

CQ WW exchange is an RST report (599) plus the station's CQ zone (two digits). The Beijing area is in CQ zone 24 (per the exam key), so the report is 59924 (A). Options with 00/44/20 would imply zones 00/44/20, which are not the Beijing zone.

The exchange "599NJ" is an RST report (599) plus a US state/section (NJ = New Jersey). The ARRL 160-Meter Contest uses exchanges of "RST + state/province", so a two-letter US state abbreviation like NJ points to that contest (A). CQWW and CQ WPX use serial-number exchanges; ALL ASIAN uses "RST + age/zone" style, none of which yields a US state code.

The Maidenhead Grid Square Locator (网格定位系统) is a geographic-reference system that divides the Earth's surface into grid squares using longitude and latitude (A). It is not a satellite positioning system (B), nor is it keyed to call-sign series (C) or administrative divisions (D). The example OM89 is a 4-character grid derived from longitude/latitude.

The Maidenhead format alternates letter and digit pairs: a 4- character grid is two letters + two digits (e.g., OM89); a 6- character (subsquare) grid adds two more letters + two digits (e.g., OM89xx) (A). The other formats (pure digits, pure letters, or prefix-based) do not describe the Maidenhead scheme.