This Technician Question of the Week is actually multiple questions related to repeaters with brief explanations for each. Reference the current Ham Radio 101 Article, Introduction to Repeaters, for more information related to this subset of questions from the Technician Class question pool about repeaters.
T1F09: What type of amateur station simultaneously retransmits the signal of another amateur station on a different channel or channels?
A. Beacon station
B. Earth station
C. Repeater station
D. Message forwarding station
Answer: Clearly, the answer here is C. Repeater station. A repeater is simply a special type of amateur station designed to instantaneously retransmit your signal when it is properly received by the repeater. Repeaters usually help extend the reach of your transceiver by retransmitting from a high elevation and perhaps with greater power than is provided by your transmitter in reaching the repeater. The most popular type of repeaters in the US are FM repeaters on VHF and UHF frequencies (2-meter band, 1.25-meter band, and 70-centimeter band).
T1F10: Who is accountable should a repeater inadvertently retransmit communications that violate the FCC rules?
A. The control operator of the originating station
B. The control operator of the repeater
C. The owner of the repeater
D. Both the originating station and the repeater owner
Answer: A repeater is just a dumb parrot operating on automatic control most of the time (Question T1E08). It has no means of filtering the content of its repeated transmissions. It is not possible for a repeater operator to constantly monitor and moderate transmissions being repeated by the machine. Thus, the correct answer here is A. The control operator of the originating station. The ham originating transmissions to the repeater is responsible for adhering to all FCC Part 97 rules.
T2A01: What is the most common repeater frequency offset in the 2 meter band?
A. plus 500 kHz
B. plus or minus 600 kHz
C. minus 500 kHz
D. Only plus 600 kHz
Answer: The offset is the difference between the “listen” frequency and the “talk” frequency used by the repeater, or viewed from the repeater’s perspective, the difference between the repeater’s transmit and receive frequencies (Question T4B11). From the repeater user’s perspective, the listen frequency is used to monitor the repeater’s transmission and the talk frequency is used to transmit to the repeater. The offset may be positive (+) or negative (-): If the talk frequency is higher (above) the listen frequency, the offset is positive (+); if the talk frequency is lower (below) the listen frequency, the offset is negative (-). Each amateur band has a designated standard value for the offset, and in the 2-meter band the standard offset is plus or minus 600 kHz (0.6 MHz). The standard offset for the 70-centimeter band is +/- 5 MHz (Question T2A03). The 1.25-meter band offset standard is -1.6 MHz. The correct answer for this question regarding the 2-meter band offset is B. plus or minus 600 kHz.
T2A04: What is an appropriate way to call another station on a repeater if you know the other station’s call sign?
A. Say “break, break” then say the station’s call sign
B. Say the station’s call sign then identify with your call sign
C. Say “CQ” three times then the other station’s call sign
D. Wait for the station to call “CQ” then answer it
Answer: Because FM repeaters typically offer clear, mostly noise-free communication, plain language is the norm. Because FM repeaters are quite popular, especially in high population areas, efficient operations are also desirable. The most plain and efficient way to call another station when you know the other station’s call sign is B. Say the station’s call sign then identify with your call sign. Rather than using “CQ” to indicate that you are listening on a repeater and wish to make a contact, simply say your call sign (Question T2A09).
T2B04: Which of the following common problems might cause you to be able to hear but not access a repeater even when transmitting with the proper offset?
A. The repeater receiver requires audio tone burst for access
B. The repeater receiver requires a CTCSS tone for access
C. The repeater receiver may require a DCS tone sequence for access
D. All of these choices are correct
Answer: The answer here is D. All of these choices are correct. Many repeaters require a special method of opening its receiver’s squelch. An audio tone burst is a tone of a specific frequency at the beginning of a transmission to a repeater that opens the receiver squelch for the extent of the transmission. The continuous tone-coded squelch system (CTCSS) uses one of 42 low audio frequencies transmitted continuously with a signal directed to a repeater to keep the squelch open, and the repeater usually filters out the tone in retransmission. Digital-coded squelch (DCS) includes a digital stream transmitted as variable frequencies to keep the repeater receiver’s squelch open. You must include the required squelch opening signal in your transmission to a repeater, and these are readily facilitated in most modern transceiver memory channel setup functions. Without the correct squelch-opening method in your transmission, the repeater will ignore your transmissions even though you can monitor the repeater’s transmissions.
Other questions related to repeaters: T1A08, T1A09, T1A11, T1D07