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| | [[home |Ham Basics]] | [[test |About The Test]] | [[Reference |References]] ^ [[sections |Study Sections]] | | |
| ====== Simplex ====== | ====== Simplex ====== |
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| [[wp>Personal_radio_service |Personal radio services]] like CB or FRS require no license but have their power output regulated to a maximum of 4 Watts (for CB bands) and 2 Watts (for FRS bands). Ham radios, however, can be operated to hundreds of watts depending on the band, mode, and license type. This complicates the "range" question a bit. | [[wp>Personal_radio_service |Personal radio services]] like CB or FRS require no license but have their power output regulated to a maximum of 4 Watts (for CB bands) and 2 Watts (for FRS bands). Ham radios, however, can be operated to hundreds of watts depending on the band, mode, and license type. This complicates the "range" question a bit. |
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| For example, imagine that Anna and Bob can barely manage to hear each other at 5 W. What would happen if Anna cranks up her TX power to 50 W? Would that help her hear Bob better? | For example, imagine that Alice and Bob can barely manage to hear each other at 5 W. What would happen if Alice cranks up her transmit (TX) power to 50 W? Would that help her hear Bob better? |
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| Increasing your own power is like speaking louder: it helps //others// hear you better, but it doesn't help you hear them better. As such, one of the rules in ham radio is to use the minimum power required to make the contact. It's like adjusting the volume of your voice to the setting around you. You wouldn't shout to the person sitting in front of you in a quiet restaurant, but you might in a loud pub. | Increasing your own power is like speaking louder: it helps //others// hear you better, but it doesn't help you hear them better. As such, one of the rules in ham radio is to use the minimum power required to make the contact. It's like adjusting the volume of your voice to the setting around you. You wouldn't shout to the person sitting in front of you in a quiet restaurant, but you might in a loud pub. |
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| <WRAP indent> | <WRAP indent> |
| | ^ Basic ^ Basic + Advanced | | | ^ Basic ^ Advanced | |
| |DC input power to the anode or collector circuit of the transmitter stage that supplies radio frequency energy to the antenna| 250W | 1000W | | |DC input power to the anode or collector circuit of the transmitter stage that supplies radio frequency energy to the antenna| 250W | 1000W | |
| | Peak envelope output power measured across an impedance-matched load for SSB emissions| 560W | 2250W | | | Peak envelope output power measured across an impedance-matched load for SSB emissions| 560W | 2250W | |
| ===== Frequency Coordination ===== | ===== Frequency Coordination ===== |
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| As we saw on the [[.sections:intro#ham_bands_overview|previous page]], ham operators are allowed to use very specific bands of the electromagnetic spectrum, but each band is also further sub-divided for different usage. The following links from [[http://wp.rac.ca/ |Radio Amateur of Canada]] (RAC) should be printed and used as reference: | As we saw on the [[intro#ham_bands_overview|previous page]], ham operators are allowed to use very specific bands of the electromagnetic spectrum, but each band is also further sub-divided for different usage. The following links from [[http://wp.rac.ca/ |Radio Amateur of Canada]] (RAC) should be printed and used as reference: |
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| * [[http://wp.rac.ca/rac-0-30-mhz-band-plan/ |HF band plan]] | * [[http://wp.rac.ca/rac-0-30-mhz-band-plan/ |HF band plan]] |
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| Let's use the 2m band as an example. Even though, we are allowed to transmit between 144 and 148 MHz, only the following frequencies should be used for simplex, voice operation: | Let's use the 2m band as an example. Even though, we are allowed to transmit between 144 and 148 MHz, only the following frequencies should be used for simplex, voice operation: |
| <WRAP prewrap center 30rem> | <WRAP prewrap center 80%> |
| 146.415, 146.430, 146.445, 146.460, 146.475, 146.490, 146.505, 146.520, 146.535, 146.550, 146.565, 146.580, 146.595 | 146.415, 146.430, 146.445, 146.460, 146.475, 146.490, 146.505, 146.520, 146.535, 146.550, 146.565, 146.580, 146.595, 147.420, 147.450, 147.480, 147.510, 147.540, 147.570 |
| </WRAP> | </WRAP> |
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| You'll notice that they are all 0.015 MHz (or 15 kHz) apart. That's to ensure that someone talking on one frequency doesn't interfere with someone talking on another. For example, if a group is using 146.415 MHz and another is using 146.430 MHz, they probably won't bother each other, (unless they are really close to each other), but if you tune your radio to 146.420 MHz or 146.425 MHz, you might hear noise from both groups. That's because communications on a frequency also have what we call //bandwidth//. Radio signals never only take just "one" frequency. Instead, they take up a certain amount of space on the electromagnetic spectrum. | You'll notice that the first 13 channels are 0.015 MHz (or 15 kHz) apart and the last 6 channels are 30 kHz apart. That's to ensure that someone talking on one frequency doesn't interfere with someone talking on another. For example, if a group is using 146.415 MHz and another is using 146.430 MHz, they probably won't bother each other, (unless they are really close to each other), but if you tune your radio to 146.420 MHz or 146.425 MHz, you might hear noise from both groups. That's because communications on a frequency also have what we call //bandwidth//. Radio signals never only take just "one" frequency. Instead, they take up a certain amount of space on the electromagnetic spectrum. |
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| The third column of the table on the [[.sections:intro#full_frequency_list|previous page]] shows the maximum allowed bandwidth for each band. This bandwidth is regulated so that no one station takes more space than needed, which would cause interference on the other frequencies. | The fourth column of the table on the [[intro#full_frequency_list|previous page]] shows the maximum allowed bandwidth for each band. This bandwidth is regulated so that no one station takes more space than needed, which would cause interference on the other frequencies. |
| | {{ :howto:hambasics:sections:frequencytable.png }} |
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| ====== The Radio ====== | ====== The Radio ====== |
| To extend the range of VHF and UHF communications, repeater stations are often used. These stations are special radios located on mountain tops that have high quality antennas up tall towers. They work by listening on one frequency (the input) and automatically re-transmitting what they hear on another frequency (the output). The difference between the two frequencies is called the //offset//. | To extend the range of VHF and UHF communications, repeater stations are often used. These stations are special radios located on mountain tops that have high quality antennas up tall towers. They work by listening on one frequency (the input) and automatically re-transmitting what they hear on another frequency (the output). The difference between the two frequencies is called the //offset//. |
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| For example, to use [[/contact#ve7rxz |VE7RXZ]], individual radio stations need to transmit (TX) on 147.<fc #ff0000>8</fc>00 MHz (the repeater's input frequency) with a Tone of 100.0 Hz, but listen (RX) on 147.<fc #ff0000>2</fc>00 MHz (the repeater's output frequency). | For example, to use [[club_info:home#ve7rxz|VE7RXZ]], individual radio stations need to transmit (TX) on 147.<fc #ff0000>8</fc>00 MHz (the repeater's input frequency) with a Tone of 100.0 Hz, but listen (RX) on 147.<fc #ff0000>2</fc>00 MHz (the repeater's output frequency). |
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| In this case we'd say that the repeater frequency is: | In this case we'd say that the repeater frequency is: |
| */ | */ |
| ===== Repeater Use ===== | ===== Repeater Use ===== |
| To call someone, we always say their call sign first, then our own. To answer a call is more flexible, but the rules((See RBR-3, p.1 and RBR-4, Sec 9.3, p.3)) say that each station has to identify themselves in either English or French: | To call someone, we always say their call sign first, then our own. To answer a call is more flexible, but the rules((See [[https://www.ic.gc.ca/eic/site/smt-gst.nsf/eng/sf01221.html |RBR-3]], p.1 and [[https://www.ic.gc.ca/eic/site/smt-gst.nsf/eng/sf01226.html |RBR-4]], Sec 9.3, p.3)) say that each station has to identify themselves in either English or French: |
| - at the beginning of the conversation, | - at the beginning of the conversation, |
| - at least every 30 minutes during the conversation, and | - at least every 30 minutes during the conversation, and |
