HamSandwich

Repeaters, simplex, and questionable antenna choices.

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T2A

OPERATING PROCEDURES

Station operation: choosing an operating frequency, calling another station, test transmissions; Band plans: calling frequencies, repeater offsets

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T2A011 of 11

What is a common repeater frequency offset in the 2-meter band?

Why A repeater listens on one frequency and retransmits on another, and the difference between the two is the offset. On 2 meters (144-148 MHz) the standard separation used across the US is 600 kHz, so your radio transmits 600 kHz above or below the repeater's output frequency. Which direction depends on where in the band the output sits, and most radios select it automatically from the band plan.
Watch out The 5 MHz figure is the standard offset for 70 cm (440 MHz) repeaters, not for 2 meters; 500 kHz and 1 MHz are not standard offsets on any common band.
2 meters: 600 kHz. 70 cm: 5 MHz. The higher the band, the bigger the split.
HamSandwich explanation, first draft. The question and answers are the NCVEC text.
T2A022 of 11

What is the national calling frequency for FM simplex operations in the 2-meter band?

Why By long-standing US band plan convention, 146.520 MHz is the national FM simplex calling frequency on 2 meters. Simplex means transmitting and receiving on the same frequency with no repeater, so hams monitor 146.52 to make contact and then typically move to another simplex frequency for the actual conversation. It is a voluntary band plan, not an FCC rule, but it is universally followed, and many mobile rigs have a one-button 'call' key preset to it.
Watch out 446.000 MHz is the national FM simplex calling frequency, but for the 70 cm band, not 2 meters; 432.100 MHz is the 70 cm weak-signal SSB/CW calling frequency.
"Fifty-two for two meters": 146.52 FM simplex. Its 70 cm cousin is 446.00.
HamSandwich explanation, first draft. The question and answers are the NCVEC text.
T2A033 of 11

What is a common repeater frequency offset in the 70-centimeter band?

Why A repeater listens on one frequency (its input) and retransmits on another (its output); the difference is the offset, and your radio shifts its transmit frequency by that amount. On the 70-centimeter band (420-450 MHz) the standard offset used across the US is 5 MHz, either above or below the output frequency depending on the band plan in your area. The 70 cm band is wide enough (30 MHz) to support such a large split.
Watch out The 600 kHz figure is the standard offset on the 2-meter band, not 70 centimeters; 2 meters is only 4 MHz wide, so a 5 MHz split would not fit.
2 meters: 600 kHz. 70 cm: 5 MHz. Bigger band, bigger offset.
HamSandwich explanation, first draft. The question and answers are the NCVEC text.
T2A044 of 11

What is an appropriate way to call another station on a repeater if you know the other station's call sign?

Why On a repeater, calling is conversational: you say the call sign of the station you want, then give your own call sign so everyone (and the FCC's identification rule, 97.119) knows who is transmitting. That is all it takes, since repeater users are usually monitoring and the machine covers the whole area. Example: "W1ABC, this is K2XYZ."
Watch out Saying "break, break" is reserved for interrupting a conversation with urgent or emergency traffic, so using it for a routine call is poor practice. Calling CQ is an HF and weak-signal simplex habit and is generally not used on FM repeaters, where you simply announce the call sign you want.
Repeater call = "their call, your call." Save "break" for emergencies and "CQ" for HF.
HamSandwich explanation, first draft. The question and answers are the NCVEC text.
T2A055 of 11

How should you respond to a station calling CQ?

Why CQ means "calling any station," so the answer is a direct call to that specific station. Standard practice is to address the station first and then identify yourself: "W1ABC, this is K2XYZ" (or just "W1ABC K2XYZ" on CW). Saying their call first tells them the transmission is aimed at them, and your call sign at the end is what they need to write down and come back to. It also satisfies the identification requirement of 97.119 since your call sign is transmitted.
Watch out Giving your own call sign first is a common slip, but that is the pattern for calling CQ yourself or for signing off, not for answering someone. Repeating "CQ" back is wrong because the other station is not calling generally, they are the one being answered.
Address the envelope before you sign the letter: their call, then yours.
HamSandwich explanation, first draft. The question and answers are the NCVEC text.
T2A066 of 11

What is an effective way to seek a call from any phone station when not using a repeater?

Why CQ is the universal invitation on voice and CW meaning "calling any station." The standard simplex format is a short series of CQs, then "this is" and your call sign, then release and listen for a few seconds before repeating. Repeating the call in short cycles while listening between them gives stations tuning across the band a chance to find you and reply.
Watch out "QTC" is a Q signal meaning "I have a message for you," not a general call, and sending an unmodulated carrier is just a test transmission that tells listeners nothing and isn't a call for contact.
CQ sounds like "seek you": call CQ, identify, then listen.
HamSandwich explanation, first draft. The question and answers are the NCVEC text.
T2A077 of 11

What does the term "repeater offset" mean?

Why A repeater listens on one frequency (its input) and retransmits on another (its output) at the same time, so the two must be separated far enough that the transmitter does not desense the receiver. That frequency separation is the offset, and your radio applies it automatically when you transmit on a repeater channel. Standard offsets in the US are 600 kHz on 2 meters and 5 MHz on 70 cm, with 1.6 MHz commonly used on 222 MHz.
Watch out The choices about time delays describe other repeater behaviors, such as the courtesy tone or squelch tail you hear after someone unkeys, not the frequency split; offset is about hertz, not seconds.
Offset = frequency shift, not time shift. Remember 600 kHz on 2 m, 5 MHz on 70 cm.
HamSandwich explanation, first draft. The question and answers are the NCVEC text.
T2A088 of 11

What is the meaning of the procedural signal "CQ"?

Why CQ is the universal call meaning "I am seeking a contact with anyone who hears me." It is a general call, not addressed to a particular station, so any station hearing it may reply. Directed forms exist too, like "CQ DX" for distant stations or "CQ contest," but the base meaning is a call to any station.
Watch out "Contest QSO" is a made-up expansion; CQ predates and is independent of contesting, and "CQ contest" simply narrows the general call to contest participants.
CQ sounds like "seek you" - seeking anyone who will answer.
HamSandwich explanation, first draft. The question and answers are the NCVEC text.
T2A099 of 11

Which of the following is a customary way to indicate a station is listening on a repeater and looking for a contact?

Why On FM repeaters the custom is simply to announce your own call sign and say you are listening or monitoring, which tells everyone on the machine who you are and that you are available for a contact. It satisfies the identification requirement of 97.119 at the same time. Repeaters are a shared local resource, so a short, low-key announcement is preferred over a long call.
Watch out Calling "CQ" is normal on HF and simplex but is generally considered unnecessary on a repeater, and giving the repeater's call sign instead of your own does not identify you as required.
On a repeater: say your own call plus "listening" - short and self-identifying, not a long CQ.
HamSandwich explanation, first draft. The question and answers are the NCVEC text.
T2A1010 of 11

What is a band plan, beyond the privileges established by the FCC?

Why The FCC only tells you which frequency ranges and modes each license class may use; it does not say where within a band to put CW, digital, SSB, FM or satellite work. Band plans fill that gap as voluntary agreements, mostly published by the ARRL and coordinated with other groups, so that narrow modes and wide modes do not land on top of each other. Following them is a matter of courtesy and good engineering rather than law, though ignoring them is a quick way to cause interference.
Watch out The choice about a club devising a plan is close but too narrow: band plans are developed by national and international amateur organizations for everyone, not by individual clubs. Net frequency lists and operating schedules are just directories of specific activities, not a structure for the whole band.
FCC says what you MAY do; the band plan says where hams AGREE to do it. Voluntary, not regulatory.
HamSandwich explanation, first draft. The question and answers are the NCVEC text.
T2A1111 of 11

What term describes an amateur station that is transmitting and receiving on the same frequency?

Why Simplex operation means the station transmits and receives on one single frequency, so only one station can talk at a time and everyone hears each other directly without a repeater. This is the normal mode for direct radio-to-radio contacts on VHF/UHF calling frequencies such as 146.52 MHz. Repeaters, by contrast, use duplex: they receive on one frequency and retransmit on another, which is why your radio applies an offset when working through one.
Watch out Full duplex means transmitting and receiving at the same time on two different frequencies, like a telephone conversation, which is the opposite of what is described here.
Simplex = single frequency. Duplex = dual frequencies (repeater offset).
HamSandwich explanation, first draft. The question and answers are the NCVEC text.
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