Ham Radio Prep Course Questions Flashcards
When are you allowed to operate your amateur station in a foreign country?
Choose only ONE best answer.
A. When the foreign country authorizes it
B. When there is a mutual agreement allowing third-party communications
C. When authorization permits amateur communications in a foreign language
D. When you are communicating with non-licensed individuals in another country
When the foreign country authorizes it
You are allowed to operate your amateur radio equipment in foreign countries only when the country permits such operations. Each country has its own procedure and protocols when allowing U.S. amateur operators to operate their station from a foreign country. Some only require applying for a reciprocal license, while others may require a test. The countries of Yemen and North Korea currently do not allow amateur radio operations by their citizens. Some countries have serious penalties for illegal radio operations. Please do your homework and have the proper documentation before taking your amateur radio equipment into a foreign country.
Who may be the control operator of a station communicating through an amateur satellite or space station?
Choose only ONE best answer.
A. Only an Amateur Extra Class operator
B. A General class or higher licensee who has a satellite operator certification
C. Only an Amateur Extra Class operator who is also an AMSAT member
D. Any amateur whose license privileges allow them to transmit on the satellite uplink frequency
Any amateur whose license privileges allow them to transmit on the satellite uplink frequency
FCC Part 97.207 (a) states that any amateur radio station may be a space station. Also, a holder of any class of amateur license may be the control operator of a space station, subject to the privileges of the class of operator held by the control operator. So providing you have the privileges to transmit on the satellite’s uplink frequency, you are eligible to be a control operator.
What is meant by the term Third Party Communications?
Choose only ONE best answer.
A. A message from a control operator to another amateur station control operator on behalf of another person
B. Amateur radio communications where three stations are in communications with one another
C. Operation when the transmitting equipment is licensed to a person other than the control operator
D. Temporary authorization for an unlicensed person to transmit on the amateur bands for technical experiments
A message from a control operator to another amateur station control operator on behalf of another person
FCC Part 97.3 (a) (47) defines third-party communications as a message from an amateur radio control operator (first-party) of an amateur radio station to another amateur station control operator (second party) on behalf of another person (third party). This occurs every day, a good example is you have a non-licensed friend come over to your house. He sees your QSL cards from Spain and mentions that he is from Spain. You turn on your radio and contact a station from Spain. You give the microphone to your friend so he can talk to someone from his home country. Before you do this, you need to verify the United States has a third-party agreement with Spain. In this example, the United States DOES NOT have third-party agreements with Spain and you would be breaking U.S. federal law as well as laws in Spain.
Which frequency is within the 6 meter amateur band?
Choose only ONE best answer.
A. 49.00 MHz
B. 52.525 MHz
C. 28.50 MHz
D. 222.15 MHz
52.525 MHz
In the United States, the amateur radio band for 6 meters covers from 50 to 54 MHz. Learning the frequencies and bands will become come with time after operating on the bands for a little while. A good rule of thumb is to take 300,000,000 meters per second and divide by the frequency in MHz, yielding the wavelength. For example 300,000,000 divided by 50,000,000 Hz (50 MHz) = 6 meters, therefore 50 MHz is equal to the wavelength of 6 meters.
When, under normal circumstances, may a Technician class licensee be the control operator of a station operating in an exclusive Amateur Extra class operator segment of the amateur bands? Choose only ONE best answer.
A. At no time
B. When operating a special event station
C. As part of a multi-operator contest team
D. When using a club station whose trustee is an Amateur Extra class operator licensee
At no time
The purpose of the control operator is to ensure the amateur radio station is operated within the FCC’s rules. The control operator is responsible for the proper operation of the amateur station within their operating privileges. At no time may a Technician class license holder allow operations outside of their operating privileges.
What are the FCC rules regarding the use of a phonetic alphabet for station identification in the Amateur Radio Service?
Choose only ONE best answer.
A. It is required when transmitting emergency messages
B. It is prohibited
C. It is required when in contact with foreign stations
D. It is encouraged
It is encouraged
Using a phonetic alphabet such as the NATO phonetic alphabet is strongly encouraged by the FCC, but not required. Using a phonetic alphabet ensures the other amateur radio stations properly record your call sign and other important information in your transmissions. Using the phonetic alphabet during poor or difficult radio conditions on voice communications confirms the other amateur radio operator has recorded the correct information.
Which of the following VHF/UHF frequency ranges are limited to CW only?
Choose only ONE best answer.
A. 50.0 MHz to 50.1 MHz and 144.0 MHz to 144.1 MHz
B. 219 MHz to 220 MHz and 420.0 MHz to 420.1 MHz
C. 902.0 MHz to 902.1 MHZ
D. All of these choices are correct
50.0 MHz to 50.1 MHz and 144.0 MHz to 144.1 MHz
Nearly all amateur radio band plans have areas reserved for only CW and digital emissions. After referring to one of the many band plan charts, you will slowly learn the subband allocations by heart. Many radio manufacturers provide complimentary band plan charts at hamfests (ham radio flea markets) or by mail. The ARRL has several different designs available for downloading and printing, too.
Which of the following is an example of remote control as defined in Part 97?
Choose only ONE best answer.
A. Repeater operation
B. Operating the station over the internet
C. Controlling a model aircraft, boat, or car by amateur radio
D. All of these choices are correct
Operating the station over the internet
The FCC defines the control point where the control operator performs his functions. Remote operation does not mean that the control operator is away from their control point. The control operator must be at the control point at all times and the control operator indirectly controls the remote station.
Who must designate the station control operator?
Choose only ONE best answer.
A. The station licensee
B. The FCC
C. The frequency coordinator
D. The ITU
The station licensee
The amateur radio station license holder is who owns a station. Because it is their station, they can designate the control operator.
What types of international communications is an FCC-licensed amateur radio station permitted to make?
Choose only ONE best answer.
A. Communications incidental to the purposes of the Amateur Radio Service and remarks of a personal character
B. Communications incidental to conducting business or remarks of a personal nature
C. Only communications incidental to contest exchanges, all other communications are prohibited
D. Any communications that would be permitted by an international broadcast station
Communications incidental to the purposes of the Amateur Radio Service and remarks of a personal character
The FCC allows international radio communications, providing there is no business that is conducted. The FCC prohibits amateurs from conducting business transactions over ham frequencies. The federal laws in some countries carry a much stiffer penalty than the corresponding federal law in the United States.
What type of tones are used to control repeaters linked by the Internet Relay Linking Project (IRLP) protocol?
Choose only ONE best answer.
A. DTMF
B. CTCSS
C. EchoLink
D. Sub-audible
DTMF
When accessing IRLP (Internet Relay Linking Project) repeaters, the different links are activated and deactivated by using DTMF tones. The IRLP controller decodes these tones to perform the desired functions. DTMF (dual-tone multi-frequency) tones are used for several control situations when operating. Yes, these are the same tones used on Touch-Tone telephones. Other tones such as CTCSS, or subaudible tones, are a fixed single tone and can’t be easily used for control functions.
What term describes the use of a sub-audible tone transmitted along with normal voice audio to open the squelch of a receiver?
Choose only ONE best answer.
A. Carrier squelch
B. Tone burst
C. DTMF
D. CTCSS
CTCSS
Many times, to help eliminate interference from other stations or repeaters on the same frequency as your local repeater, a technique called subaudible tones will be used. This means that the repeater’s squelch will be opened only by a transmitter that transmits the proper subaudible tone. This technique was developed and implemented by Motorola under the name “Private Line” or PL. Many modern radios and programming software refer to this subaudible tone as CTCSS, or Continuous Tone-Coded Squelch System. The FCC is looking for the term CTCSS when referring to PL tones and codes. There also are digital codes that aren’t subaudible but work in the same way and are known as Digital Code Squelch, or DCS. The Motorola term for DCS is “Digital Private Line,” or DPL.
What term describes an amateur station that is transmitting and receiving on the same frequency?
Choose only ONE best answer.
A. Full duplex
B. Diplex
C. Simplex
D. Multiplex
Simplex
Simplex operation defines an amateur station that is transmitting and receiving on the same frequency. Sometimes you will hear hams asking you to go to the repeater’s transmit frequency on simplex. An example would be: “WB1XXX, this is WB2XXX. Joe, please go to 146.94 simplex.” The national calling frequency, 146.52 MHz, is used on a simplex basis.
Which Q signal indicates that you are receiving interference from other stations?
Choose only ONE best answer.
A. QRM
B. QRN
C. QTH
D. QSB
QRM
When first getting started in amateur radio, you quickly will find out many operators use a lot of different abbreviations in their conversations. Nearly all of these originated from CW operations, where it was important to keep your transmissions as short as possible by using common abbreviations. The Q signals are one example of these abbreviations; you will learn them after operating on the air for a short while, especially using CW. QRM refers to man-made interference from other amateur stations. QRN refers to interference due to static.
If a station is not strong enough to keep a repeater’s receiver squelch open, which of the following might allow you to receive the station’s signal?
Choose only ONE best answer.
A. Open the squelch on your radio
B. Listen on the repeater input frequency
C. Listen on the repeater output frequency
D. Increase your transmit power
Listen on the repeater input frequency
Usually, if another amateur station is unable to constantly keep the repeater’s receive squelch open, you can quickly monitor the repeater’s input frequency. This means you are receiving on the same frequency that the other amateur station is transmitting on. In many cases, you will be able to receive the other station. Most amateur FM transceivers have a button for “reverse split” that allows you to easily monitor the repeater’s input frequency.
What should be done when using voice modes to ensure that voice messages containing unusual words are received correctly?
Choose only ONE best answer.
A. Send the words by voice and Morse code
B. Speak very loudly into the microphone
C. Spell the words using a standard phonetic alphabet
D. All of these choices are correct
Spell the words using a standard phonetic alphabet
The propagation between two amateur stations is not always perfect and sometimes atmospheric conditions make communications difficult. When using voice modes, you are encouraged to use a phonetic alphabet to spell strange or unusual words, names, locations, etc., to ensure the voice message is received correctly.
What is meant by the term “NCS” used in net operation?
Choose only ONE best answer.
A. Nominal Control System
B. Net Control Station
C. National Communications Standard
D. Normal Communications Syntax
Net Control Station
Many times to efficiently utilize our amateur frequencies, nets will be established. A net is where multiple operators gather on one frequency. In a directed net, everyone will identify their station and state their business. The “NCS,” or Net Control Station, will recognize that station and try their best to take care of the station’s business. There are hundreds of different on-the-air nets in the world. The ARRL maintains an extensive list of nets worldwide.
What is the meaning of the procedural signal “CQ”?
Choose only ONE best answer.
A. Call on the quarter hour
B. A new antenna is being tested (no station should answer)
C. Only the called station should transmit
D. Calling any station
Calling any station
This is the process where you make a general call to any other amateur station. A good rule of thumb is to call CQ three times and then give your call sign three times. If you are using phone, it is always a good idea to use a widely recognized phonetic alphabet when giving your call sign. An example would be: “CQ CQ CQ. This is WB1XXX, Whiskey Bravo One X-ray X-ray X-ray, Whiskey Bravo One X-ray X-ray X-ray.”
Which of the following is a characteristic of good traffic handling?
Choose only ONE best answer.
A. Passing messages exactly as received
B. Making decisions as to whether messages are worthy of relay or delivery
C. Ensuring that any newsworthy messages are relayed to the news media
D. All of these choices are correct
Passing messages exactly as received
The National Traffic System takes great pride in the fact the messages that travel through their system are received exactly as they were sent. Many of the prosigns used today came from the formal traffic and message handling procedures. Each message has a “check” that is used to validate the number of words or groups in a formal message. The characteristic of good traffic handling is passing the messages exactly as they were received.
Which of the following is an accepted practice for an amateur operator who has checked into a net?
Choose only ONE best answer.
A. Provided that the frequency is quiet, announce the station call sign and location every 5 minutes
B. Move 5 kHz away from the net’s frequency and use high power to ask other hams to keep clear of the net frequency
C. Remain on frequency without transmitting until asked to do so by the net control station
D. All of these choices are correct
Remain on frequency without transmitting until asked to do so by the net control station
After checking into a net, you are to remain on frequency without transmitting until you are asked to do so by the net control station. After a group of amateur operators checks into the net, the NCS will acknowledge who has checked into the net. If your call sign was not mentioned, then you can check in again and avoid conflicting with other stations when you transmit. If for some reason you need to leave the net before it terminates, wait until there is a pause in the net, give your call sign, and request to secure your station. This is important in traffic nets because the net control may direct formal messages to your station and you would have left long before.
Which of the following results from the fact that skip signals refracted from the ionosphere are elliptically polarized?
Choose only ONE best answer.
A. Digital modes are unusable
B. Either vertically or horizontally polarized antennas may be used for transmission or reception
C. FM voice is unusable
D. Both the transmitting and receiving antennas must be of the same polarization
Either vertically or horizontally polarized antennas may be used for transmission or reception
When radio waves bounce – or skip – off the ionosphere and are refracted back to earth, many times they lose their original polarization and become elliptically polarized. The elliptically polarized signals contain properties of both vertical and horizontal polarization. Because of this distortion from the original polarization, either a vertically or horizontally polarized antenna may be used for transmitting or receiving.
What is the formula for converting frequency to approximate wavelength in meters?
Choose only ONE best answer.
A. Wavelength in meters equals frequency in hertz multiplied by 300
B. Wavelength in meters equals frequency in hertz divided by 300
C. Wavelength in meters equals frequency in megahertz divided by 300
D. Wavelength in meters equals 300 divided by frequency in megahertz
Wavelength in meters equals 300 divided by frequency in megahertz
The formula for converting frequency to an approximate wavelength is 300 divided by the frequency in megahertz. So using this formula, let’s take our constant of 300 million meters per second and divide it by the national calling frequency of 146.52 MHz. The millions cancel out, so the answer is 2.047474 meters, or you can say that 146.52 MHz is in the 2-meter amateur band. Remember, on the FCC exam you are asked to pick the most correct answer, so 2.047474 meters is closer to 2 meters than 20 meters.
How does the wavelength of a radio wave relate to its frequency?
Choose only ONE best answer.
A. The wavelength gets longer as the frequency increases
B. The wavelength gets shorter as the frequency increases
C. There is no relationship between wavelength and frequency
D. The wavelength depends on the bandwidth of the signal
The wavelength gets shorter as the frequency increases
There is a direct relationship between the wavelength of radio waves and frequency. As the wavelength gets shorter, the frequency increases – just like the strings on a musical instrument where the shorter the string the higher the frequency of the note.
What causes tropospheric ducting?
Choose only ONE best answer.
A. Discharges of lightning during electrical storms
B. Sunspots and solar flares
C. Updrafts from hurricanes and tornadoes
D. Temperature inversions in the atmosphere
Temperature inversions in the atmosphere
Sometimes warmer air becomes trapped above cooler air. This is called temperature inversion or thermal inversion. This atmospheric condition allows for a condition called tropospheric ducting.
Which of the following is an advantage of HF vs VHF and higher frequencies?
Choose only ONE best answer.
A. HF antennas are generally smaller
B. HF accommodates wider bandwidth signals
C. Long-distance ionospheric propagation is far more common on HF
D. There is less atmospheric interference (static) on HF
Long-distance ionospheric propagation is far more common on HF
The amateur radio VHF and UHF and above bands are mostly for communications with other stations that are within line of sight. These bands depend on repeaters to increase their effective range. The HF bands are well suited for long-range communications because their radio waves are reflected back toward earth instead of punching through the ionosphere. The ability of HF frequencies to bounce off the ionosphere and provide long-distance propagation is far more common.
What are the two components of a radio wave?
Choose only ONE best answer.
A. AC and DC
B. Voltage and current
C. Electric and magnetic fields
D. Ionizing and non-ionizing radiation
Electric and magnetic fields
Radio waves are made up of both electric and magnetic fields. This is why you sometimes will see radio waves referred to as electromagnetic waves. Think about a circuit that helps tune your antenna; the capacitor stores energy in an electric field, the inductor stores energy in a magnetic field. But these two different properties work together to create a resonate circuit.
What is a characteristic of VHF signals received via auroral reflection?
Choose only ONE best answer.
A. Signals from distances of 10,000 or more miles are common
B. The signals exhibit rapid fluctuations of strength and often sound distorted
C. These types of signals occur only during winter nighttime hours
D. These types of signals are generally strongest when your antenna is aimed west
The signals exhibit rapid fluctuations of strength and often sound distorted
Sometimes you will hear other amateur stations on VHF that are much farther away than your local repeater coverage or line-of-sight communications. Their signals will exhibit rapid fluctuations of strength and often sound distorted. These distorted signals are being received via auroral reflection.
What antenna polarization is normally used for long-distance weak-signal CW and SSB contacts using the VHF and UHF bands?
Choose only ONE best answer.
A. Right-hand circular
B. Left-hand circular
C. Horizontal
D. Vertical
Horizontal
Most man-made RF noise and static is vertically polarized. On the VHF and UHF bands, horizontally polarized antennas are normally better for long-distance weak-signal CW and SSB contacts.
What property of a radio wave is used to describe its polarization?
Choose only ONE best answer.
A. The orientation of the electric field
B. The orientation of the magnetic field
C. The ratio of the energy in the magnetic field to the energy in the electric field
D. The ratio of the velocity to the wavelength
The orientation of the electric field
This is one of those questions that you must read very carefully to make sure you understand what is being asked. A radio wave contains two properties, electric waves, and magnetic waves, therefore the name “electromagnetic waves.” The property of the electric field is used to describe the polarization. So just remember radio waves travel at the speed of light and the polarization does not affect the speed of the radio waves. Other distractors such as the ratio of velocity to wavelength have no effect on the polarization.
Why are direct (not via a repeater) UHF signals rarely heard from stations outside your local coverage area?
Choose only ONE best answer.
A. They are too weak to go very far
B. FCC regulations prohibit them from going more than 50 miles
C. UHF signals are usually not reflected by the ionosphere
D. UHF signals are absorbed by the ionospheric D layer
UHF signals are usually not reflected by the ionosphere
Usually, the ionosphere has little or no effect on UHF radio waves. Because of not being reflected back to the earth, you rarely will receive UHF transmissions from other amateur stations outside your local area. Because VHF and UHF signals are able to easily penetrate the ionosphere, instead of being reflected back to the earth, these bands are well suited for EME (Earth-Moon-Earth, or moonbounce) activities.
Which of the following is an appropriate receive filter bandwidth for minimizing noise and interference for SSB reception?
Choose only ONE best answer.
A. 500 Hz
B. 1000 Hz
C. 2400 Hz
D. 5000 Hz
2400 Hz
A single-sideband (SSB) bandwidth should not exceed 3 kHz. The appropriate receive bandwidth for SSB reception would be 2400 Hz or 2.4 kHz.
What is the advantage of having multiple receive bandwidth choices on a multimode transceiver?
Choose only ONE best answer.
A. Permits monitoring several modes at once
B. Permits noise or interference reduction by selecting a bandwidth matching the mode
C. Increases the number of frequencies that can be stored in memory
D. Increases the amount of offset between receive and transmit frequencies
Permits noise or interference reduction by selecting a bandwidth matching the mode
Today’s multimode transceivers have multiple bandwidth choices or filters available to the amateur operator. These filters allow you to eliminate, or reduce, noise and interference. You will select the bandwidth option that matches the mode you are using. Narrow modes such as CW allow you to use a narrow bandwidth such as 250 Hz or 500 Hz. Single-sideband bandwidth is limited to 3 kHz, but most stations do not use that much bandwidth so a 2.4-kHz filter is best for SSB. Digital modes such as FT8 pack as many different signals as possible into a 3-kHz bandwidth. In this case, your 3-kHz or 3.5-kHz bandwidth option would be the best selection.
Where should the negative return connection of a mobile transceiver’s power cable be connected?
Choose only ONE best answer.
A. At the battery or engine block ground strap
B. At the antenna mount
C. To any metal part of the vehicle
D. Through the transceiver’s mounting bracket
At the battery or engine block ground strap
The negative power cable to your radio should be connected to the battery or the engine block ground strap. The battery or the engine block ground strap is the answer the FCC is expecting for this question. In real life, please consult with the vehicle’s manufacturer if unsure. Some newer vehicles use the negative battery connection to determine current drain, thus your radio connection might cause inaccurate readings or problems. Many electric vehicles have voltages in excess of 12 volts flowing through some wiring harnesses. If unsure, please consult with an expert or professional.
Which of the following is an appropriate receive filter bandwidth for minimizing noise and interference for CW reception?
Choose only ONE best answer.
A. 500 Hz
B. 1000 Hz
C. 2400 Hz
D. 5000 Hz
500 Hz
The bandwidth of a CW (continuous wave) transmission is dependent on the speed of the CW transmissions. Typically a CW transmission is only 25 Hz when sending 5 words per minute (WPM) to 15 WPM. When using CW, choosing the 500-Hz bandwidth option would be the appropriate option for minimizing noise and interference for CW reception.
How might a computer be used as part of an amateur radio station?
Choose only ONE best answer.
A. For logging contacts and contact information
B. For sending and/or receiving CW
C. For generating and decoding digital signals
D. All of these choices are correct
All of these choices are correct
Nowadays, a computer in an amateur station is as important as a power supply. Computers are used to perform logging of other stations you communicate with. Many contest managers expect all log submissions to be computer-generated. Many operators use their computers to send and receive CW. Nearly all the digital modes found on the amateur bands require a computer to encode and decode transmissions. In order to get the full benefit out of some amateur radio software programs, a connection is needed from the computer to the radio for rig control or CAT (computer-aided transceiver) control.
How is a computer’s sound card used when conducting digital communications?
Choose only ONE best answer.
A. The sound card communicates between the computer CPU and the video display
B. The sound card records the audio frequency for video display
C. The sound card provides audio to the radio’s microphone input and converts received audio to digital form
D. All of these choices are correct
The sound card provides audio to the radio’s microphone input and converts received audio to digital form
The sound card is a very important piece of digital communications in an amateur station. The sound card provides the audio into the radio’s microphone input and converts the received audio into a digital form. There are some companies that make high-quality sound cards that are external to the one built into the computer. Several of the newer amateur transceivers have sound cards built into the radio.
What is the proper location for an external SWR meter?
Choose only ONE best answer.
A. In series with the feed line, between the transmitter and antenna
B. In series with the station’s ground
C. In parallel with the push-to-talk line and the antenna
D. In series with the power supply cable, as close as possible to the radio
In series with the feed line, between the transmitter and antenna
This is another question that individuals get correct on the FCC exam and then fail in real life when assembling their station. The SWR (standing wave ratio) measures the standing waves, or the amount of RF energy reflected back from your feed line and antenna. A high SWR can damage your transceiver. You want to place your SWR meter in series with the feed line – between the transmitter and your antenna. Most modern radios have an SWR meter built-in.
Which computer sound card port is connected to a transceiver’s headphone or speaker output for operating digital modes?
Choose only ONE best answer.
A. Headphone output
B. Mute
C. Microphone or line input
D. PCI or SDI
Microphone or line input
When operating digital modes, including CW, the operation becomes very easy when using your computer’s sound card to perform all the work. Some individuals become confused at this point. You simply want to connect the audio output from the radio to the audio input to the computer. The radio’s audio output usually comes from the transceiver’s headphones or speaker. The audio input to the computer goes to the microphone or line input. Connect the audio of the radio to the input of the computer. In this case, the sound card’s microphone or line input port would be used.
Which of the following could be used to remove power line noise or ignition noise?
Choose only ONE best answer.
A. Squelch
B. Noise blanker
C. Notch filter
D. All of these choices are correct
Noise blanker
Ignition noise and power line noise always has affected reception for amateurs over the years. The noise blanker circuits in most radios are able to effectively eliminate nearly all manmade noise such as power line Interference and vehicle ignition noise.
What is the purpose of the squelch control on a transceiver?
Choose only ONE best answer.
A. To set the highest level of volume desired
B. To set the transmitter power level
C. To adjust the automatic gain control
D. To mute receiver output noise when no signal is being received
To mute receiver output noise when no signal is being received
The squelch control on an amateur transceiver is to “squelch” or “mute” the noise when no signal is being received on the frequency you are monitoring. Sometimes when radio conditions are just right weaker stations will fade in strong enough to open your squelch settings. By increasing the squelch gain, you can easily eliminate unwanted interference.
What is the voltage across each of two components in parallel with a voltage source?
Choose only ONE best answer.
A. It is determined by the type and value of the components
B. Half the source voltage
C. Twice the source voltage
D. The same voltage as the source
The same voltage as the source
When electronic components are in parallel, the voltage across each of the components is the same as the voltage source. The current flowing through each component depends on its type and value. If you add up the current flow for each individual component, you will have the total current flow for the whole parallel circuit.
In which type of circuit is current the same through all components?
Choose only ONE best answer.
A. Series
B. Parallel
C. Resonant
D. Branch
Series
When the current flowing through all components in a circuit is nearly the same amount, you can assume that the components in the circuit are in series.
What is the voltage across a 10-ohm resistor if a current of 2 amperes flows through it?
Choose only ONE best answer.
A. 8 volts
B. 0.2 volts
C. 12 volts
D. 20 volts
20 volts
Using the key pieces of information we need to solve the problem, what is the voltage across a 10-ohm resistor if a current of 2 amperes flows through it? They are looking for E (volts), you are given R (resistance) of 10 ohms and you are given I (current) of 2 amperes. Looking at Ohm’s Law, we quickly see that amperes multiplied by ohms equals volts, or E = I x R. Thus, 10 ohms multiplied by 2 amperes equals 20 volts, or 10 x 2 = 20.
What is the formula used to calculate electrical power in a DC circuit?
Choose only ONE best answer.
A. Power (P) equals voltage (E) multiplied by current (I)
B. Power (P) equals voltage (E) divided by current (I)
C. Power (P) equals voltage (E) minus current (I)
D. Power (P) equals voltage (E) plus current (I)
Power (P) equals voltage (E) multiplied by current (I)
Ohm’s Law provides the amateur operator with many useful formulas. You will use many of these formulas frequently during your time as an amateur radio operator. Calculating power is one of those basic formulas. P (power) = E (voltage) multiplied by I (current). This sometimes is referred to as amps x volts = watts.
How many microfarads are equal to 1,000,000 picofarads?
Choose only ONE best answer.
A. 0.001 microfarads
B. 1 microfarad
C. 1000 microfarads
D. 1,000,000,000 microfarads
1 microfarad
1 farad = 1,000,000 microfarads. 1 microfarad = 1,000,000 picofarads.
What is the ability to store energy in an electric field called?
Choose only ONE best answer.
A. Inductance
B. Resistance
C. Tolerance
D. Capacitance
Capacitance
The energy stored by the electric field is expressed in its capacitance. Capacitors are constructed with two plates. When voltage is applied between these two plates, a potential difference is created along with an electric field. Potential energy is held in the electric field. When the capacitor is discharged, the potential energy stored in the electric field is converted to the charge.
What is the approximate amount of change, measured in decibels (dB), of a power increase from 5 watts to 10 watts?
Choose only ONE best answer.
A. 2 dB
B. 3 dB
C. 5 dB
D. 10 dB
3 dB
When working with decibels, every 3 dB of gain multiplies your signal by 2. Every 3 dB of loss divides your signal by 2. Thus, going from 5 watts to 10 watts is 3 dB of gain. And going from 10 watts to 5 watts is 3 dB of loss.
Which of the following is equal to 500 milliwatts?
Choose only ONE best answer.
A. 0.02 watts
B. 0.5 watts
C. 5 watts
D. 50 watts
0.5 watts
1 watt = 1000 milliwatts. Thus, 1/2 (0.5) watt = 500 milliwatts.
What formula is used to calculate voltage in a circuit?
Choose only ONE best answer.
A. Voltage (E) equals current (I) multiplied by resistance (R)
B. Voltage (E) equals current (I) divided by resistance (R)
C. Voltage (E) equals current (I) added to resistance (R)
D. Voltage (E) equals current (I) minus resistance (R)
Voltage (E) equals current (I) multiplied by resistance (R)
Using Ohm’s Law, E (voltage) equals I (current) multiplied by R (resistance), or E = I x R.
In which type of circuit is voltage the same across all components?
Choose only ONE best answer.
A. Series
B. Parallel
C. Resonant
D. Branch
Parallel
When the voltage across all components in a circuit is nearly the same amount, you can assume that the components in the circuit are in parallel.
Which of the following battery types is rechargeable?
Choose only ONE best answer.
A. Nickel-metal hydride
B. Lithium-ion
C. Lead-acid gel-cell
D. All of these choices are correct
All of these choices are correct
The most common types of rechargeable batteries are lead-acid, nickel-metal hydride (NiMH) and lithium-ion (Li-ion). Older handheld amateur radios still use the original nickel-cadmium (NiCd).
Which of the following battery types is not rechargeable?
Choose only ONE best answer.
A. Nickel-cadmium
B. Carbon-zinc
C. Lead-acid
D. Lithium-ion
Carbon-zinc
Carbon-zinc batteries are not rechargeable. The chemical reactions that produce electricity are not reversible. Do not try to recharge carbon-zinc batteries as they may leak or could explode.
Which of these components can be used as an electronic switch or amplifier?
Choose only ONE best answer.
A. Oscillator
B. Potentiometer
C. Transistor
D. Voltmeter
Transistor
A transistor is classified as a semiconductor device. The transistor is commonly used as an amplifier or as a switch to control electric signals and power.
What type of circuit controls the amount of voltage from a power supply?
Choose only ONE best answer.
A. Regulator
B. Oscillator
C. Filter
D. Phase inverter
Regulator
A regulator is a type of circuit that controls the amount of voltage from a power supply. Sometimes you will see this circuit referred to as a voltage regulator. Some power supply designs use a single chip to perform this task while other designs perform voltage regulation with many separate and independent components.
What electrical component opposes the flow of current in a DC circuit?
Choose only ONE best answer.
A. Inductor
B. Resistor
C. Voltmeter
D. Transformer
Resistor
A resistor opposes the flow of current in a DC circuit. The unit of measure for a resistor is an ohm.
What electrical component is used to connect or disconnect electrical circuits?
Choose only ONE best answer.
A. Magnetron
B. Switch
C. Thermistor
D. All of these choices are correct
Switch
Probably the common electrical component used to connect or disconnect electrical circuits is the switch. Yes, it’s just like the light switch in your house or garage. Nearly all electrical circuits have a switch to connect or disconnect power to the circuit.
Which of the following devices or circuits changes an alternating current into a varying direct current signal?
Choose only ONE best answer.
A. Transformer
B. Rectifier
C. Amplifier
D. Reflector
Rectifier
A rectifier changes an alternating current into a varying direct current signal. A rectifier is composed of diodes to direct the flow of current into specific directions in the electronic circuit. This arrangement is commonly used in power supplies to send the positive side of the alternating current’s sine wave to one part of the circuit and the negative side to another part of the circuit.
What is a relay?
Choose only ONE best answer.
A. An electrically controlled switch
B. A current-controlled amplifier
C. An optical sensor
D. A pass transistor
An electrically-controlled switch
A relay is an electric switch. A relay uses an electromagnet to switch the current flow. A relay is commonly used where a small amount of current can use mechanical contacts to control the flow of a much larger current.
Which of the following is a resonant or tuned circuit?
Choose only ONE best answer.
A. An inductor and a capacitor connected in series or parallel to form a filter
B. A type of voltage regulator
C. A resistor circuit used for reducing standing wave ratio
D. A circuit designed to provide high-fidelity audio
An inductor and a capacitor connected in series or parallel to form a filter
An inductor and a capacitor connected in series or parallel to form a filter is a resonant or tuned circuit. Remember, a resonant or tuned circuit is composed of an L (inductor) and a C (capacitor). Sometimes you will see this referred to as an LC circuit.
What is a transceiver?
Choose only ONE best answer.
A. A type of antenna switch
B. A unit combining the functions of a transmitter and a receiver
C. A component in a repeater that filters out unwanted interference
D. A type of antenna matching network
A unit combining the functions of a transmitter and a receiver
A transceiver is a single unit that combines a transmitter and a receiver. Many older pieces of amateur radio equipment consisted of separate transmitter and receiver units.
What reading on an SWR meter indicates a perfect impedance match between the antenna and the feed line?
Choose only ONE best answer.
A. 2 to 1
B. 1 to 3
C. 1 to 1
D. 10 to 1
1 to 1
A 1 to 1 reading on an SWR meter indicates a perfect impedance match between the antenna and the feed line. The 1 to 1 reading would be expressed as 1:1. Some amateur radio transmitters will fail to transmit and give an antenna fault if the SWR is over 2:1. Other transmitters will automatically reduce the power output until the SWR moves into an acceptable range.
Where is an RF preamplifier installed?
Choose only ONE best answer.
A. Between the antenna and receiver
B. At the output of the transmitter’s power amplifier
C. Between a transmitter and antenna tuner
D. At the receiver’s audio output
Between the antenna and receiver
An RF preamplifier amplifies the received signal when working with weak signal reception. The RF preamplifier goes between the receiver and the antenna; the closer it is placed to the antenna will provide the best performance. If you install the RF preamplifier close to the receiver, you will never recover the signals you lost because of feedline losses.
Which of the following instruments can be used to determine if an antenna is resonant at the desired operating frequency?
Choose only ONE best answer.
A. A VTVM
B. An antenna analyzer
C. A Q meter
D. A frequency counter
An antenna analyzer
An antenna analyzer is an instrument that can be used to determine whether an antenna is resonant at the desired operating frequency. The antenna analyzer puts out a tiny signal just like your own transmitter, except the antenna analyzer can determine the reactance, impedance, standing wave ratio, and resonant frequency of the antenna being evaluated, and in some cases, it can detect a cable fault in your feed line.
What does a dummy load consist of?
Choose only ONE best answer.
A. A high-gain amplifier and a TR switch
B. A non-inductive resistor and a heat sink
C. A low-voltage power supply and a DC relay
D. A 50 ohm reactance used to terminate a transmission line
A non-inductive resistor and a heat sink
A dummy load consists of a non-inductive resistor and a heat sink. Some dummy loads use a dry heat sink such as a block of aluminum with fins, while others employ a wet heat sink that consists of the non-inductive resistor submerged in oil. The volume of oil is the actual heat sink. Dummy load devices allow for the testing of transmitters without causing interference on the air.
What should be the first step to resolve cable TV interference from your ham radio transmission?
Choose only ONE best answer.
A. Add a low-pass filter to the TV antenna input
B. Add a high-pass filter to the TV antenna input
C. Add a preamplifier to the TV antenna input
D. Be sure all TV coaxial connectors are installed properly
Be sure all TV coaxial connectors are installed properly
The first stop to resolve cable TV interference from your amateur radio transmission would be to verify and make sure all TV coaxial connectors are properly installed. In a cable TV installation, incorrectly installed coaxial connectors can act as antennas, allowing your transmissions to enter the cable system.
What does an SWR reading of 4:1 indicate?
Choose only ONE best answer.
A. Loss of -4 dB
B. Good impedance match
C. Gain of +4 dB
D. Impedance mismatch
Impedance mismatch
An SWR (standing wave ratio) reading of 4:1 indicates an impedance mismatch. Given a transmitter putting out 100 watts, 36 of those watts would be reflected back into the transmitter with an SWR of 4:1. A best practice is to keep your SWR below 1.5:1.
Why should the outer jacket of coaxial cable be resistant to ultraviolet light?
Choose only ONE best answer.
A. Ultraviolet resistant jackets prevent harmonic radiation
B. Ultraviolet light can increase losses in the cable’s jacket
C. Ultraviolet and RF signals can mix, causing interference
D. Ultraviolet light can damage the jacket and allow water to enter the cable
Ultraviolet light can damage the jacket and allow water to enter the cable
The outer jacket of the coaxial cable should be resistant to ultraviolet light, otherwise, UV can damage the jacket and allow water to enter the cable.
Which of the following is a way to reduce or eliminate interference from an amateur transmitter to a nearby telephone?
Choose only ONE best answer.
A. Put a filter on the amateur transmitter
B. Reduce the microphone gain
C. Reduce the SWR on the transmitter transmission line
D. Put an RF filter on the telephone
Put an RF filter on the telephone
Installing an RF filter on the telephone is a way to reduce or eliminate interference from an amateur transmitter to a nearby telephone. If they have multiple telephones, you may have to install an RF filter on each telephone as well as a filter where the phone line comes into the house.
Which of the following precautions should be taken when measuring circuit resistance with an ohmmeter?
Choose only ONE best answer.
A. Ensure that the applied voltages are correct
B. Ensure that the circuit is not powered
C. Ensure that the circuit is grounded
D. Ensure that the circuit is operating at the correct frequency
Ensure that the circuit is not powered
When measuring circuit resistance with an ohmmeter, always ensure that the circuit is not powered or energized. This is for both personal safety and the safety of your test equipment. When taking measurements using test equipment, always devote your full attention to what you are doing.
Which of the following types of emission has the narrowest bandwidth?
Choose only ONE best answer.
A. FM voice
B. SSB voice
C. CW
D. Slow-scan TV
CW
CW (continuous wave) or Morse code emissions have the narrowest bandwidth. CW transmissions normally use only about 25 Hz of bandwidth, depending on the speed of the transmission. On VHF and UHF amateur bands, FM typically uses about 10 kHz of bandwidth for voice transmission. SSB and SSTV normally use about 3 kHz of bandwidth for a typical signal. From the list of given modes, CW has the narrowest bandwidth.
What is an electronic keyer?
Choose only ONE best answer.
A. A device for switching antennas from transmit to receive
B. A device for voice-activated switching from receive to transmit
C. A device that assists in manual sending of Morse code
D. An interlock to prevent unauthorized use of a radio
A device that assists in manual sending of Morse code
A device that assists in the manual sending of Morse code is known as an electronic keyer. An amateur uses a set of keyer paddles connected to the electronic keyer to send Morse code. The electronic keyer will either send a dot or dash perfectly depending on which side of the keyer paddle is pressed. Most electronic keyers have built-in memory for sending preprogrammed messages, which is especially useful in radio contesting where the same message is sent over and over or for calling CQ.
Which of the following is a form of amplitude modulation?
Choose only ONE best answer.
A. Spread spectrum
B. Packet radio
C. Single sideband
D. Phase shift keying (PSK)
Single sideband
SSB (single sideband) is one form of amplitude modulation. Simply put, the louder your voice the more the amplitude of the carrier. Of all the different variations of amplitude modulation, SSB is the most common voice mode on amateur radio HF bands.
What type of transmission is indicated by the term “NTSC?”
Choose only ONE best answer.
A. A Normal Transmission mode in Static Circuit
B. A special mode for earth satellite uplink
C. An analog fast scan color TV signal
D. A frame compression scheme for TV signals
An analog fast scan color TV signal
NTSC (National Television System Committee) is the name of the standard used to encode colors in an analog fast-scan color TV signal. ATV (amateur television) is another mode of communication you are allowed to use with your license. Some larger cities have ATV repeaters.
Which of the following are provided by satellite tracking programs?
Choose only ONE best answer.
A. Maps showing the real-time position of the satellite track over the earth
B. The time, azimuth, and elevation of the start, maximum altitude, and end of a pass
C. The apparent frequency of the satellite transmission, including effects of Doppler shift
D. All of these choices are correct
All of these choices are correct
There are many key pieces of information that are provided by amateur satellite tracking programs and smartphone apps. Most all amateur satellite tracking programs give the user the apparent frequency of the satellite transmission, including effects of Doppler shift. The programs also provide an easy-to-read display of the time, azimuth, and elevation of the start, maximum altitude, and end of the pass, all plotted on maps showing the real-time position of the satellite track over Earth.
Which of the following operating activities is supported by digital mode software in the WSJT suite?
Choose only ONE best answer.
A. Moonbounce or Earth-Moon-Earth
B. Weak-signal propagation beacons
C. Meteor scatter
D. All of these choices are correct
All of these choices are correct
Meteor scatter, WSPR weak-signal propagation beacons and moonbounce (Earth-moon-Earth) are a few operating activities supported by digital mode software in the WSJT suite. Other weak-signal modes such as FT8 and FT4 for HF and JT9 for LF (low frequency) and MW (medium wave) communications also are supported in the WSJT suite of protocols. Note which mode you choose for which band. For example, running MSK144 (meteor scatter) on 10 meters is illegal because the symbol rate may exceed the baud rate limit set by the FCC. MSK144 is for 6 meters and above where the baud rate limit set by the FCC is higher.
How is access to some IRLP nodes accomplished?
Choose only ONE best answer.
A. By obtaining a password that is sent via voice to the node
B. By using DTMF signals
C. By entering the proper internet password
D. By using CTCSS tone codes
By using DTMF signals
IRLP (Internet Radio Linking Project) nodes are accessed by using DTMF (dual-tone multi-frequency) tones. Nearly all VHF/UHF mobile transceivers and handheld radios have these Touch-Tone keypads on either their front panel or integrated into their microphone. Some repeaters also require a password to be used in addition to the DTMF tones.
Which type of voice mode is most often used for long-distance (weak signal) contacts on the VHF and UHF bands?
Choose only ONE best answer.
A. FM
B. DRM
C. SSB
D. PM
SSB
SSB (single sideband) voice mode is most often used for long-distance (weak signal) contacts on the VHF and UHF bands. There are several VHF and UHF contests where nearly all voice contacts are made via SSB, while other contacts are made using CW. Horizontally polarized antennas are most commonly used for SSB communications on VHF and UHF amateur frequencies.
What is FT8?
Choose only ONE best answer.
A. A wideband FM voice mode
B. A digital mode capable of operating in low signal-to-noise conditions that transmits on 15-second intervals
C. An eight-channel multiplex mode for FM repeaters
D. A digital slow-scan TV mode with forward error correction and automatic color compensation
A digital mode capable of operating in low signal-to-noise conditions that transmits on 15-second intervals
FT8 is a digital mode capable of operating in low signal-to-noise conditions that transmits on 15-second intervals. FT8 was developed by Joe Taylor, K1JT, and Steve Franke, K9AN, thus “FT,” and the signal is 8-FSK, thus the 8. FT8 allows your station to auto sequence from one message to the next for quick and efficient communications. FT8 typically allows communications with stations that have a signal-to-noise ratio of -10 dB to -15 dB with no problem.
Which of the following is a good way to judge whether your uplink power is neither too low nor too high?
Choose only ONE best answer.
A. Check your signal strength report in the telemetry data
B. Listen for distortion on your downlink signal
C. Your signal strength on the downlink should be about the same as the beacon
D. All of these choices are correct
Your signal strength on the downlink should be about the same as the beacon
Verifying that your signal strength on the downlink is about the same as the beacon is a good way to judge whether your uplink power is either too low or too high. If your signal is too weak, it will be difficult for other stations to understand, and if your signal is too strong, you will shut down satellite access for everyone else. Comparing your signal to the satellite’s beacon signal is a good indication that your amount of power and/or ERP (effective radiated power) is just about right.
What is the impedance of most coaxial cables used in amateur radio installations?
Choose only ONE best answer.
A. 8 ohms
B. 50 ohms
C. 600 ohms
D. 12 ohms
50 ohms
50 ohms is the impedance of most coaxial cables used in amateur installations. Nearly all amateur radio transmitters are designed to use coaxial feed lines with a 50-ohm impedance. The coaxial cable used for television, CATV, cable and satellite installations is all 75 ohm. At first glance, the cable looks the same, but a close examination of the cable type printed on the jacket will allow you to reference the specifications on a data sheet.
What is an advantage of using a properly mounted 5/8 wavelength antenna for VHF or UHF mobile service?
Choose only ONE best answer.
A. It has a lower radiation angle and more gain than a 1/4 wavelength antenna
B. It has very high angle radiation for better communicating through a repeater
C. It eliminates distortion caused by reflected signals
D. It has 10 times the power gain of a 1/4 wavelength design
It has a lower radiation angle and more gain than a 1/4 wavelength antenna
The advantage of using a properly mounted 5/8-wavelength antenna for VHF or UHF mobile service is the lower radiation angle and more gain than a quarter-wavelength antenna. The angle of radiation is important in this application, or where does the signal go when it leaves the antenna. With the 5/8 wavelength antenna, the signal stays closer to the Earth for a greater distance, while the signal with a quarter-wavelength antenna rises sharply from the Earth. The 5/8-wavelength antenna has nearly a 2-dB gain over the quarter-wavelength antenna. Therefore, the 5/8-wavelength antenna has a longer range and more gain when compared to the 1/4 wavelength antenna.
Which of the following describes a type of antenna loading?
Choose only ONE best answer.
A. Inserting an inductor in the radiating portion of the antenna to make it electrically longer
B. Inserting a resistor in the radiating portion of the antenna to make it resonant
C. Installing a spring in the base of a mobile vertical antenna to make it more flexible
D. Strengthening the radiating elements of a beam antenna to better resist wind damage
Inserting an inductor in the radiating portion of the antenna to make it electrically longer
Inserting an inductor in the radiating portion of the antenna to make it electrically longer describes a type of antenna loading. Inductors inserted in series with the radiating portion of the antenna will make the antenna appear electrically longer to your amateur transmitter. This technique is useful when you have limited space for your low-frequency antennas. They can be physically shorter, but electrically, they will be the proper length.
In general, what happens as the frequency of a signal passing through a coaxial cable is increased?
Choose only ONE best answer.
A. The characteristic impedance decreases
B. The loss decreases
C. The characteristic impedance increases
D. The loss increases
The loss increases
Generally, the loss increases as the frequency of a signal passing through the coaxial cable is increased. This is why coaxial cable used in VHF and UHF installations costs more than coaxial cable used on HF frequencies. Longer runs of coaxial cable for VHF and UHF installations should be avoided, if possible. Your antenna system is one of the most important pieces of your station.
What can cause erratic changes in SWR readings?
Choose only ONE best answer.
A. The transmitter is being modulated
B. A loose connection in an antenna or a feed line
C. The transmitter is being over-modulated
D. Interference from other stations is distorting your signal
A loose connection in an antenna or a feed line
A loose connection in an antenna or feed line can cause erratic changes in SWR (standing wave ratio) readings. Moisture in the coax from improper weatherproofing is another cause of erratic SWR readings. These problems can be easily reduced by good mechanical and electrical bonding of all connections and weatherproofing.
What is the approximate length, in inches, of a quarter-wavelength vertical antenna for 146 MHz?
Choose only ONE best answer.
A. 112
B. 50
C. 19
D. 12
19
The approximate length, in inches, of a quarter-wavelength vertical antenna for 146 MHz will be 19 inches. Let’s break down the math: they want the length of an antenna in inches based on a given frequency. The tried-and-true formula for quarter-wavelength antennas is to divide 234 by the frequency in MHz. 234 / frequency in MHz = Antenna length in feet. Therefore, 234 / 146 MHz = 1.602 feet. To convert feet to inches, multiply by 12. Therefore, 1.602 feet x 12 = 19.2 inches.
Which of the following types of feed line has the lowest loss at VHF and UHF?
Choose only ONE best answer.
A. 50-ohm flexible coax
B. Multi-conductor unbalanced cable
C. Air-insulated hard line
D. 75-ohm flexible coax
Air-insulated hard line
An air-insulated hard line is a type of feed line that has the lowest loss at VHF and UHF frequencies. The larger the coaxial cable, the more difficult it becomes to work with. Hardline cable is not very flexible. Coaxial connectors for the larger coax sometimes can cost more than $50 each. Most high-powered commercial installations use air-insulated hardline coaxial feed lines because of the low loss. Many times this cable finds its way into the hands of lucky hams.
What is the major function of an antenna tuner (antenna coupler)?
Choose only ONE best answer.
A. It matches the antenna system impedance to the transceiver’s output impedance
B. It helps a receiver automatically tune in weak stations
C. It allows an antenna to be used on both transmit and receive
D. It automatically selects the proper antenna for the frequency band being used
It matches the antenna system impedance to the transceiver’s output impedance
The major function of an antenna tuner (antenna coupler) is to match the antenna system impedance to the transceiver’s output impedance. Many new amateur radio operators will compromise on their antenna when first getting on the air. In order to overcome the inefficiencies of a non-resonant antenna, they will use an antenna tuner. The antenna tuner is only matching the transceiver’s output impedance of 50 ohms to the antenna. If the mismatch is too great, the antenna tuner will absorb the energy mismatch and convert the energy that was not transferred to the antenna into heat.
What is a disadvantage of the “rubber duck” antenna supplied with most handheld radio transceivers when compared to a full-sized quarter-wave antenna?
Choose only ONE best answer.
A. It does not transmit or receive as effectively
B. It transmits only circularly polarized signals
C. If the rubber end cap is lost, it will unravel very easily
D. All of these choices are correct
It does not transmit or receive as effectively
The disadvantage of the “rubber duck” antenna supplied with most handheld radio transceivers when compared to a full-sized quarter-wave antenna is that they do not transmit or receive as effectively. Rubber duck antennas offer more convenience than performance. There is nothing wrong with owning two separate antennas for your handheld radio. The rubber duck can be used for close-quarter or tactical communications where most everyone or the repeater is in line of sight. A quarter-wave antenna can be substituted for conditions where performance is a priority such as hiking or locations farther away from other individuals or the repeater.
Why is it important to have low SWR when using coaxial cable feed line?
Choose only ONE best answer.
A. To reduce television interference
B. To reduce signal loss
C. To prolong antenna life
D. All of these choices are correct
To reduce signal loss
It is important to have a low SWR (standing wave ratio) when using a coaxial cable feed line to reduce signal loss. An SWR of 1:1 has virtually no power being reflected back into the transmitter. So with a 100-watt transmitter, virtually 100 percent (100 watts) will radiate from the antenna. An SWR of 2:1 means 11% (11 watts) of your signal is being reflected back into the transmitter. So with a 100-watt transmitter, only 89 watts are being radiated from the antenna. With a 5:1 SWR, only 55.6 watts will be radiated from the antenna. This reflected power back into your station can cause unwanted interference in other electronic devices in your house or your neighbor’s house.
Which of the following is true when installing grounding conductors used for lightning protection?
Choose only ONE best answer.
A. Only non-insulated wire must be used
B. Wires must be carefully routed with precise right-angle bends
C. Sharp bends must be avoided
D. Common grounds must be avoided
Sharp bends must be avoided
When installing grounding conductors used for lightning protection, sharp bends must be avoided. Lightning likes to travel in a straight line. Lightning can’t flow through conductors that make sharp turns and possibly could jump from the grounding conductor to surrounding equipment at the point of the sharp bend or turn. The potential for additional damage and possible fire hazard is possible with grounding conductors that do not follow a straight line.
Which of the following is an acceptable method to determine that your station complies with FCC RF exposure regulations?
Choose only ONE best answer.
A. By calculation based on FCC OET Bulletin 65
B. By calculation based on computer modeling
C. By measurement of field strength using calibrated equipment
D. All of these choices are correct
All of these choices are correct
Calculations based on FCC OET Bulletin 65, based on computer modeling, and measurement of field strength using calibrated equipment are all acceptable methods to determine that your station complies with FCC RF exposure regulations. Any time you make changes to your station, a good practice is to re-evaluate your RF Exposure limits after all changes have been completed.
What is the maximum power level that an amateur radio station may use at VHF frequencies before an RF exposure evaluation is required?
Choose only ONE best answer.
A. 1500 watts PEP transmitter output
B. 1 watt forward power
C. 50 watts PEP at the antenna
D. 50 watts PEP reflected power
50 watts PEP at the antenna
50 watts PEP (peak envelope power) at the antenna is the maximum power level that an amateur station may use at VHF frequencies before an RF exposure evaluation is required. The FCC has released Supplement B, the amateur radio supplement, to OET Bulletin 65. This supplement contains the guidelines for RF exposure in amateur stations. The complex calculations have been removed and all the information needed is in an easy-to-read table.
If the averaging time for exposure is 6 minutes, how much power density is permitted if the signal is present for 3 minutes and absent for 3 minutes rather than being present for the entire 6 minutes?
Choose only ONE best answer.
A. 3 times as much
B. 1/2 as much
C. 2 times as much
D. There is no adjustment allowed for shorter exposure times
2 times as much
If the averaging time for exposure is 6 minutes and the signal is present for 3 minutes and absent for 3 minutes, then the power density permitted is two times as much. The averaging time is 6 minutes, the transmitter is on for 3 minutes, thus 6 divided by 3 equals 2 times as much. If the transmitter was on for two minutes and off for two minutes then the power density would be 3 times as much.
Why is duty cycle one of the factors used to determine safe RF radiation exposure levels?
Choose only ONE best answer.
A. It affects the average exposure of people to radiation
B. It affects the peak exposure of people to radiation
C. It takes into account the antenna feed line loss
D. It takes into account the thermal effects of the final amplifier
It affects the average exposure of people to radiation
The transmitter’s duty cycle is one of the factors used to determine safe RF radiation exposure levels as it affects the average exposure of people to radiation. The FCC and OSHA use time, distance, and shielding for limiting factors concerning RF exposure. You limit the time you are close to the radiating source, you increase the distance between you and the radiating source and you employ any shielding that can be maneuvered between you and the antenna or radiating source, such as a metal building or foil-backed insulation.
How can you make sure your station stays in compliance with RF safety regulations?
Choose only ONE best answer.
A. By informing the FCC of any changes made in your station
B. By re-evaluating the station whenever an item of equipment is changed
C. By making sure your antennas have low SWR
D. All of these choices are correct
By re-evaluating the station whenever an item of equipment is changed
Re-evaluating your amateur station whenever an item of equipment is changed or reconfigured is one way you can make sure your station stays in compliance with RF safety regulations. The best practice is to keep all your RF evaluation information and station configuration information with your station records. In the unlikely event the FCC asks for your station documentation, everything will be together in one place. Many operators keep the configuration changes in their log book on the blank pages. They then always have the permanent log and configuration of their station. This is very handy to document when you buy each piece of equipment. Finally, if a little one disconnects some of your pretty cables, you have the latest connection diagrams with your station configuration.
What is considered to be a proper grounding method for a tower?
Choose only ONE best answer.
A. A single four-foot ground rod, driven into the ground no more than 12 inches from the base
B. A ferrite-core RF choke connected between the tower and ground
C. Separate eight-foot long ground rods for each tower leg, bonded to the tower and each other
D. A connection between the tower base and a cold water pipe
Separate eight-foot long ground rods for each tower leg, bonded to the tower and each other
The proper grounding method for a tower is to use separate eight-foot-long ground rods for each tower leg, bonded to the tower and each other. The ARRL has an excellent book written by Ward Silver. Remember: Think safety. If you have questions or you are unsure of your tower and antenna installation, please consult with licensed professionals.
What should be done to all external ground rods or earth connections?
Choose only ONE best answer.
A. Waterproof them with silicone caulk or electrical tape
B. Keep them as far apart as possible
C. Bond them together with heavy wire or conductive strap
D. Tune them for resonance on the lowest frequency of operation
Bond them together with heavy wire or conductive strap
A good practice is for all external ground rods or Earth connections to be bonded together with heavy wire or conductive straps. The ARRL has an excellent book on this subject written by H. Ward Silver.
Which of the following actions might amateur operators take to prevent exposure to RF radiation in excess of FCC-supplied limits?
Choose only ONE best answer.
A. Relocate antennas
B. Relocate the transmitter
C. Increase the duty cycle
D. All of these choices are correct
Relocate antennas
Relocating antennas is an action an amateur radio operator can take to prevent exposure to RF radiation in excess of the FCC-supplied limits. Limiting the amount of time you are in the field of radiation from the antenna is another action an amateur radio operator can take to prevent exposure to RF radiation, except it is not always practical. Increasing the distance between you and the antenna is the easiest way to limit your radiation exposure. The distance from your antenna is inversely proportional to the square of the distance. For example, if you double the distance from your antenna, you reduce the radiation exposure by a fourth. If you are 5 feet from your antenna and the exposure at your body is 100 watts, then if you move another 5 feet from the antenna (double the distance) your RF exposure to your body is now 25 watts.
What safety equipment should always be included in home-built equipment that is powered from 120V AC power circuits?
Choose only ONE best answer.
A. A fuse or circuit breaker in series with the AC hot conductor
B. An AC voltmeter across the incoming power source
C. An inductor in parallel with the AC power source
D. A capacitor in series with the AC power source
A fuse or circuit breaker in series with the AC hot conductor
A fuse or circuit breaker in series with the AC hot conductor is one piece of safety equipment that always should be included in home-built equipment that is powered from 120-volt AC power circuits. Interlocks to remove AC power from home-built equipment when the cover is removed is another example of safety equipment that can be installed.
