Copyright: Copyright ® 1997 Tony Lacy.


GENERAL Class.

FCC License Preparation

Element 3B

To go to an explanation press the Search button and select the required question designator.


G1AO1
G1A01:

General class operators have full privileges over the entire 160 meter band.  [97.301]


G1A02
G1A02:

General class operators have privileges in two areas of this band.  In the first area, CW, RTTY, and data privileges exist from 3,525 kHz to 3,750 kHz.  In the second area, CW, voice, and image privileges exist between 3,850 kHz and 4,000 kHz.  [97.301]


G1A03
G1A03:

General class operators have privileges in two areas of this band.  In the first area, CW, RTTY and data privileges exist from 7,025 kHz to 7,150 kHz.  In the second area, CW, voice, and image privileges exist between 7,225 kHz and 7,300 kHz.  [97.301]


G1A04
G1A04:

General class operators have CW, RTTY, and data privileges over the entire 30 meter band.  [97.301]


G1A05
G1A05:

General class operators have privileges in two areas of the 20 meter band.  In the first area, CW, RTTY, and data privileges exist from 14.025 MHz to 14.150 MHz.  In the second area, CW, voice, and image privileges exist between 14.225 MHz and 14.350 MHz.  [97.301]


G1A06
G1A06:

General class operators have privileges in two areas of the 15 meter band.  In the first area, CW, RTTY, and data privileges exist from 21.025 MHz to 21.200 MHz.  In the second area, CW, voice, and image privileges exist between 21.300 MHz and 21.450 MHz.  [97.301]


G1A07
G1A07:

General class operators have full privileges on the entire 12 meter band.  The CW, RTTY, and data modes may be used from 24.890 MHz to 24.930 MHz.  The CW, phone, and image modes may be used from 24.930 MHz to 24.990 MHz.  [97.301]


G1A08
G1A08:

General class operators have privileges over the entire 10 meter band.  The CW, RTTY, and data modes may be used from 28.000 MHz to 28.300 MHz.  The CW, phone, and image modes may be used from 28.300 MHz to 29.700 MHz.  [97.305]


G1A09
G1A09:

General class operators have privileges over the entire 160 meter band.  This band is not divided into sections.  The whole band is available for CW, RTTY, data, phone and image transmissions from 1.800 MHz to 2.000 MHz.  [97.301]


G1A10
G1A10:

General class operators have privileges for two areas on the 80 meter band.  The CW and data modes may be used from 3,525 kHz to 3,750 kHz.  The CW, image, and phone modes may be used from 3,850 kHz to 4,000 kHz.  [97.301]


G1A11
G1A11:

The 7.225 MHz - 7.300 MHz section is the only part of the 40 meter band where General class operators have priviledges for image transmissions.  [97.305]


G1A12
G1A12:

General class operators have RTTY and data privileges over the entire 30 meter band from 10.100 MHz to 10.150 MHz.  [97.305]


G1A13
G1A13:

General class privileges cover part of the area designated for image transmissions on the 20 meter band.  This area is from 14.225 MHz to 14.350 MHz.  [97.305]


G1A14
G1A14:

General class privileges cover part of the area designated for image transmissions on the 15 meter band.  This area is from 21.300 MHz to 21.450 MHz.  [97.305]


G1A15
G1A15:

General class privileges cover the entire area designated for image and phone transmissions on the 12 meter band.  [97.305]


G1A16
G1A16:

General class privileges cover the entire area designated for image and phone transmissions on the 10 meter band.  [97.305]


G1A17
G1A17:

If you are a General class operator and you are operating on a frequency that General class privileges cover.  However, if the station license does not have these privileges, then you must add your call sign to the station call sign.  [97.119]


G1A18
G1A18:

It is the license held by control operator that determines the privileges held by a repeater station.  [97.205]


G1A19
G1A19:

Repeaters are usually located on hills or tall buildings.  They have efficient antenna(s) for receiving and transmitting.  This means that a weak local signal from a handheld transceiver will be re-broadcasted at higher power.  The higher power signal from the high antenna location will give a tremendously increased range.  On the receiving side, a repeater will pick up the weakest of signals from a wide area.  Then, it will retransmit them at higher power to the handheld.

Principle of repeater operation:


G1A20
G1A20:

The interference has to be making communications difficult or impossible to be classed as harmful.  Harmful interference is not necessarily deliberate.  [97.3]


G1A21
G1A21:

This rule applies to all international amateur communications.  Some countries (Great Britain for example) do not permit third party communications by normal amateur radio communications.  [97.117]


G1B01
G1B01:

If you live near an airport, special rules apply.  [97.25]


G1B02
G1B02:

The correct option is a direct quotation from the FCC rules.  [97.101]


G1B03
G1B03:

A beacon station is an automatic station operated by a radio amateur.  It is one that transmits an identification signal.  Beacon stations are used to determine propagation conditions.  If a beacon can be heard from a particular location then there is a chance that you can work amateur radio stations in that location.


G1B04
G1B04:

The other reasons are all permitted by the FCC rules [97.111] and [97.113].


G1B05
G1B05:

This is a specific exception to the rule of no music.  [97.113]


G1B06
G1B06:

Certain codes used in data transmission are permitted since their purpose is not to obscure the meaning of the communication.  [97.113]


G1B07
G1B07:

This is a reference to the Amateur Q-codes and the abbreviations used in CW work.  They are permitted since their purpose is not to obscure the meaning of the communication.  [97.113]


G1B08
G1B08:

Certain codes used in data transmission are permitted since their purpose is not to obscure the meaning of the communication.  [97.113]


G1B09
G1B09:

Certain codes used in data transmission are permitted since their purpose is not to obscure the meaning of the communication.  [97.113]


G1B10
G1B10:

All the other options are specifically prohibited by the FCC rules.  [97.113]


G1B11
G1B11:

You need to stop the music from being re-transmitted by your station.  [97.113]


G1C01
G1C01:

There is a blanket power limit of 1,500 watts, but specific power limits apply to certain sub-bands such as the range 3.675 - 3.725 in the 80 meter band.  [97.313]


G1C02
G1C02:

There is a blanket power limit of 1,500 watts.  No specific power limit is given in the FCC rules for this frequency.  [97.313]


G1C03
G1C03:

There is a blanket power limit of 1,500 watts, but specific power limits apply to certain sub-bands such as 10.10 - 10.15 MHz.  [97.313]


G1C04
G1C04:

There is a blanket power limit of 1,500 watts, but specific power limits apply to certain sub-bands such as 21.10 - 21.20 MHz.  [97.313]


G1C05
G1C05:

There is a blanket power limit of 1,500 watts; no specific power limit is given in the rules for this frequency.  [97.313]


G1C06
G1C06:

The FCC rules allow power amplifiers to be built to operate below 144 MHz.  Under certain conditions, they do not need FCC type acceptance.  [97.315]


G1C07
G1C07:

The FCC rules allow power amplifiers to be built to operate below 144 MHz.  Under certain conditions, they do not need FCC type acceptance.  This is one of those conditions.  [97.315]


G1C08
G1C08:

High gain high power amplifiers are prone to emission of noise and spurious outputs.  The rules are an attempt to limit the gain of high power RF amplifiers.  [97.317]


G1C09
G1C09:

All the other options are specifically mentioned in the rules.  [97.317]


G1C10
G1C10:

Transmission above this data rate is specifically prohibited for each band below 28 MHz.  One reason is to restrict bandwidth on amateur radio transmissions on the crowded HF amateur bands.  [97.305]


G1C11
G1C11:

Transmission above this data rate is specifically prohibited for each band below 28 MHz.  One reason is to restrict bandwidth on amateur radio transmissions on the crowded HF amateur bands.  [97.305]


G1D01
G1D01:

It makes sense to restrict the tester to preparing tests at a lower level than his/her own.  [97.507]


G1D02
G1D02:

It makes sense to restrict the tester to preparing tests at a lower level than his/her own.  [97.507]


G1D03
G1D03:

It makes sense to restrict the tester to preparing tests at a lower level than his/her own.  [97.507]


G1D04
G1D04:

In other words, this means the 5 WPM code test and the Novice written examination.  This is a minimum requirement.  You may take the 13 WPM or 20 WPM code tests instead of the 5 WPM test!  If you feel you have a chance of passing a code test at higher speed than you need, then take it in addition to the test you feel you are sure of passing.  [97.503]


G1D05
G1D05:

Applicants for the Technician class take the Novice examination plus an extra Technician examination.  [97.501]


G1D06
G1D06:

This is called the Technician Plus class.  Applicants for this class must obtain the requirements for the Technician class and pass the 5 WPM code test [97.501].


G1D07
G1D07:

They must be present and observing the applicants.  [97.509]


G1D08
G1D08:

Each of the VE's must be accredited by the coordinating VEC.  [97.509]


G1D09
G1D09:

When you have a CSCE you may use your new General class privileges with your existing call sign, so long as you add the identifier /AG to the end of it.  [97.119]


G1D10
G1D10:

When you have a CSCE you may use your new General class privileges with your existing call sign, so long as you add the identifier /AG to the end of it.  [97.119]


G1D11
G1D11:

When you have a CSCE you may use your new General class privileges with your existing call sign, so long as you add the identifier /AG to the end of it.  [97.119]


G2A01
G2A01:

We use lower side band on 160, 75 and 40 meters, upper side band on the higher bands.


G2A02
G2A02:

We use lower side band on 160, 75 and 40 meters, upper side band on the higher bands.


G2A03
G2A03:

This is a convention; the regulations allow RTTY from 3.500 MHz to 3.750 MHz.  [97.305]


G2A04
G2A04:

This is a convention.  In fact, the rules permit RTTY between 14.000 MHz and 14.150 MHz.  [97.305]


G2A05
G2A05:

Baudot code is used by RTTY amateur operators.  The term "RTTY" is another name for teleprinters.  These are typewriter-like machines used for sending and receiving text by radio.


G2A06
G2A06:

ASCII stands for "American Standard Code for Information Interchange."  This code is used by most computers.  There are enough bits to represent each character of the alphabet in upper and lower case, as well as many other symbols.  Parity bits are used for error detection.


G2A07
G2A07:

The frequency shift is the distance between the frequency that represents "space" and the frequency that represents "mark".  In an RTTY transmission the carrier frequency rapidly jumps from one to the other giving a characteristic sound.


G2A08
G2A08:

Mode A (ARQ) stands for Automatic repeat request and mode B (FEC) stands for frame error check.  This is all part of the handshaking that goes on when two computers are communicating.


G2A09
G2A09:

This separation is also called the offset or split.  The output frequency is normally the higher of the two.


G2A10
G2A10:

VOX is also called Voice Operated Control; your transceiver automatically switches to transmit as you speak.  It is often used by telephony operators on the HF bands.


G2A11
G2A11:

Full break-in telegraphy puts great technical demands on the receiver that has to achieve full sensitivity from a desensitized state in between each transmitted "dit" and "dah".


G2B01
G2B01:

This is the polite thing to do.  Late arrivals to your net will easily be able to find you.


G2B02
G2B02:

Paragraph [97.101] of FCC part 97 regulations is relevant here.


G2B03
G2B03:

After a contact is made, it is not uncommon to have to QSY to a clear frequency.


G2B04
G2B04:

The required bandwidth of a CW transmission is typically a few tens of Hz.  However, receiver bandwidths are usually set to a few hundred Hz for CW work.  So, allow a safety margin.


G2B05
G2B05:

The bandwidth of a SSB transmission is around 3 kHz.  The receiver bandwidth is usually set to this width during SSB contacts.


G2B06
G2B06:

Although the bandwidth of a RTTY signal is a few hundred Hz it is polite to allow a safety margin.  This is because the station receiving the RTTY signal may have its receiver filter set wider than this.


G2B07
G2B07:

Another name for this sort of map is a "Great Circle" map.  This is because the shortest path around the surface of a spherical object such as the Earth is called a Great Circle.  Although the country shapes and areas appear distorted, the directions are correct from locations at the center of the map.  These maps are great for setting your beam in the correct direction to work a foreign country.  Be sure to choose an "azimuthal" map with your location near the center.


G2B08
G2B08:

Another name for this sort of map is a "Great Circle" map.  This is because the shortest path around the surface of a spherical object such as the Earth is called a Great Circle.  Although the country shapes and areas appear distorted, the directions are correct from locations at the center of the map.  These maps are great for setting your beam in the correct direction to work a foreign country.  Be sure to choose an "azimuthal" map with your location near the center.


G2B09
G2B09:

Since we live on the surface of a sphere, there are at least two direct paths to any location.  We can either take the short route or we can go in the opposite direction (180 degrees) and get to the location by the long route.


G2B10
G2B10:

For example, a 20 meter band plan will show where CW, RTTY, and data transmissions exist.  It will also show where telephony transmissions are found.


G2B11
G2B11:

Here is a map of the ITU regions:


G2C01
G2C01:

In a life threatening emergency, all the rules can be waived.


G2C02
G2C02:

Radio amateurs have a vital role in disaster situations.


G2C03
G2C03:

If you were to join the Radio Amateur Civil Emergency Service (RACES) and an emergency occurred, you could find yourself passing traffic to and from Civil Defense organizations.


G2C04
G2C04:

If you were to join the Radio Amateur Civil Emergency Service (RACES) and an emergency occurred, you could find yourself passing traffic to and from Civil Defense organizations.


G2C05
G2C05:

In a life threatening emergency, all the rules can be waived.


G2C06
G2C06:

In a life threatening emergency, all the rules can be waived.  This includes the requirement to only use authorized amateur radio frequencies.


G2C07
G2C07:

Then, you must pass on the information to the appropriate people by the best means that you have.


G2C08
G2C08:

All classes of licensee are eligible to become RACES members.


G2C09
G2C09:

The relevant FCC regulation is in [97.117].


G2C10
G2C10:

Amateur Auxiliaries police the airwaves.  They try to sort out problems where amateurs may be violating FCC rules, inadvertently or otherwise.


G2C11
G2C11:

Amateur Auxiliaries police the airwaves.  They try to sort out problems where amateurs may be violating FCC rules, inadvertently or otherwise.


G3A01
G3A01:

Sometimes, the problem is due to an intensification of the low frequency absorbing D-layer.  This atmospheric layer readily absorbs lower frequencies.  Moving to a higher band may allow your signals to propagate farther.


G3A02
G3A02:

Sometimes, the problem is due to an intensification of the low frequency absorbing D-layer.  This atmospheric layer readily absorbs lower frequencies.  Moving to a higher band may allow your signals to propagate farther.


G3A03
G3A03:

This radiation travels at the speed of light.  Particles from the sun take several days to arrive.


G3A04
G3A04:

The term "flux" means flow.  Solar flux is the rate at which radio energy is flowing out of the sun.  The first radio telescope was a VHF antenna pointed at the sun.


G3A05
G3A05:

The "solar flux index" is a measurement of solar flux at a frequency of 2,800 MHz.  This frequency was chosen for the measurement because at this frequency the "radio" sun looks the same size as the "visible" sun.  The solar flux measurements are taken at midday at Penticon (in British Columbia).  Propagation forecasts are derived from the measurements.  These forecasts are broadcast on WWV every hour.  The solar flux measurement varies from about 67 units (very low) to around 300 units (very high).  The higher the reading, the better the propagation conditions on HF.


G3A06
G3A06:

Not only do solar storms create disturbances to radio propagation, they also affect the earth's magnetic field.  Sometimes the effect is great enough to temporarily alter magnetic compass readings.


G3A07
G3A07:

Those parts of the earth at latitudes greater than 45 degrees (nearer the poles) are subject to greater levels of geomagnetic disturbance.  This is because the lines of force of the earth's magnetic field are more closely packed and more vertical.  This tends to channel ionized particles down to levels that can cause disturbances.


G3A08
G3A08:

Those parts of the earth at latitudes greater than 45 degrees (nearer the poles) are subject to greater levels of geomagnetic disturbance.  This is because the lines of force of the earth's magnetic field are more closely packed and more vertical.  This tends to channel ionized particles down to levels that can cause disturbances.


G3A09
G3A09:

In this question, tropospheric ducting effects are regarded as occurring with ground waves.  All other non line-of-sight communications depend on reflected waves from the ionized layers of the atmosphere.  These layers are a result of solar activity.  OK, so there is moon bounce and repeater operation as well…


G3A10
G3A10:

Electromagnetic emissions include ultraviolet light as well as X-rays.  Particles are also emitted from the sun.  They take about two days to arrive.


G3A11
G3A11:

The critical frequency of the reflecting layers increases with increasing ionization.  When sunspot numbers are high, this indicates a period of higher solar flux.  This results in greater levels of ionization.


G3B01
G3B01:

The best chance for a successful contact is on the next band down in frequency from the maximum useable frequency (MUF).  If you go too far down in frequency, your signals may be affected by absorption in the D-layer.


G3B02
G3B02:

The best chance for a successful contact is on the next band down in frequency from the maximum useable frequency (MUF).  If you go too far down in frequency your signals may be affected by absorption in the D-layer.


G3B03
G3B03:

The sun rotates once every 28 days.  The radiation that enhances radio communications is emitted from specific areas that appear on the sun's surface.  (These areas will appear and disappear over periods of several months.)


G3B04
G3B04:

This is the main purpose of amateur beacon stations.


G3B05
G3B05:

When they reach the earth, they are reflected upwards again.  The bouncing process continues on and on.


G3B06
G3B06:

There are beacons on all the important amateur bands.


G3B07
G3B07:

Atmospheric ionization will be low and the MUF will be not much above 20 MHz.


G3B08
G3B08:

The most reliable long distance band is the 20 meter band.  (Therefore, it is also the most crowded band.)  Absorption of radio signals in the D-layer is low at this frequency and the MUF is always above 14 MHz


G3B09
G3B09:

Gray line propagation occurs along the earth's terminator for a short period, twice per day.


G3B10
G3B10:

The F2-layer is at over 200 miles in altitude and is the highest of the reflecting layers.  It has the longest hop distance of all.


G3B11
G3B11:

The E-layer is the lowest of the reflecting layers at about 70 miles and so the maximum  hop distance is less than with F layer propagation.


G3C01
G3C01:

The E-layer is the lowest of the reflecting layers at about 70 miles and so the maximum  hop distance is less than with F layer propagation.


G3C02
G3C02:

This is the period of maximum solar flux.  It is solar radiation that produces the ionized layers in the atmosphere.


G3C03
G3C03:

The F2-layer is at over 200 miles in altitude.  It is the highest of the reflecting layers.  The F1-layer and F2-layer merge into one layer at night when it is called the F-layer.


G3C04
G3C04:

As the angle approaches the vertical, it becomes more likely that the signal will pass straight through the layer.  For maximum chance of reflection you want an angle that is as low as possible.  Low angle radiation will result in longer hops.


G3C05
G3C05:

The D-layer is the lowest one.  Unlike the other layers it does not enhance radio communication by reflecting signals toward the ground.  It absorbs low frequency signals most strongly.


G3C06
G3C06:

Scatter signals are a result of signals bouncing off transient irregularities in the ionized layers and other brief disturbances in the atmosphere.  It is the short lived nature of the irregularities that causes the wavering of the signal.  Also there will be several different paths involved.  Each of the paths will be rapidly changing.  This will cause cancellation and addition effects.


G3C07
G3C07:

Scatter signals are a result of signals bouncing off transient irregularities in the ionized layers and other brief disturbances in the atmosphere.  It is the short lived nature of the irregularities that causes the wavering of the signal.  Also there will be several different paths involved.  Each of the paths will be rapidly changing.  This will cause cancellation and addition effects.


G3C08
G3C08:

Scatter signals are a result of signals bouncing off transient irregularities in the ionized layers and other brief disturbances in the atmosphere.  These irregularities are small and so the amount of reflected signal is small.  High transmitted powers are used for communication using scatter modes.


G3C09
G3C09:

Scatter signals are a result of signals bouncing off transient irregularities in the ionized layers and other brief disturbances in the atmosphere.  It is the short lived nature of the irregularities that causes the wavering of the signal.  Also there will be several different paths involved.  Each of the paths will be rapidly changing.  This will cause cancellation and addition effects.


G3C10
G3C10:

Above the MUF, most of the signal passes straight through the ionized layer.  A small amount of signal will be scattered in all directions.  This can be used for communication by scatter mode.  High transmitted power is required for communication using scatter mode.


G3C11
G3C11:

Multi-path fading can often be recognized by its regular nature.  The signal level will rise and fall every few seconds.


G4A01
G4A01:

This is often called the two-tone test.  It is the simplest and cheapest method of testing a SSB transmitter.  Two non-harmonically related audio sine wave signals are used to emulate the speech signal.  The resulting detected output is viewed on an oscilloscope.  It is important that the two tones are good sine waves.  Appreciable non-linearity of the RF amplifier will show up in the oscilloscope pattern.  A more sensitive test is to listen for intermodulation products from a two tone test using a receiver.

Two tone test, correctly adjusted transmitter:

Two tone test, PA bias incorrect:

Two tone test, overdriven with flat topping:


G4A02
G4A02:

This is often called the two-tone test.  It is the simplest and cheapest method of testing a SSB transmitter.  Two non-harmonically related audio sine wave signals are used to emulate the speech signal.  The resulting detected output is viewed on an oscilloscope.  It is important that the two tones are good sine waves.  Appreciable non-linearity of the RF amplifier will show up in the oscilloscope pattern.  A more sensitive test is to listen for intermodulation products from a two tone test using a receiver.

Two tone test, correctly adjusted transmitter:

Two tone test, PA bias incorrect:

Two tone test, overdriven with flat topping:


G4A03
G4A03:

This is often called the two-tone test.  It is the simplest and cheapest method of testing a SSB transmitter.  Two non-harmonically related audio sine wave signals are used to emulate the speech signal.  The resulting detected output is viewed on an oscilloscope.  It is important that the two tones are good sine waves.  Appreciable non-linearity of the RF amplifier will show up in the oscilloscope pattern.  A more sensitive test is to listen for intermodulation products from a two tone test using a receiver.

Two tone test, correctly adjusted transmitter:

Two tone test, PA bias incorrect:

Two tone test, overdriven with flat topping:


G4A04
G4A04:

This is often called the two-tone test.  It is the simplest and cheapest method of testing a SSB transmitter.  Two non-harmonically related audio sine wave signals are used to emulate the speech signal.  The resulting detected output is viewed on an oscilloscope.  It is important that the two tones are good sine waves.  Appreciable non-linearity of the RF amplifier will show up in the oscilloscope pattern.  A more sensitive test is to listen for intermodulation products from a two tone test using a receiver.

Two tone test, correctly adjusted transmitter:

Two tone test, PA bias incorrect:

Two tone test, overdriven with flat topping:


G4A05
G4A05:

Electronic switches are very fast.  This fast switching could generate spurious signals.  The low pass filter could prevent these signals from being radiated.


G4A06
G4A06:

They are also more reliable than the older method of using a mechanical relay.


G4A07
G4A07:

Power amplifier instability can result in spurious emissions or rapid destruction of the tube.  For maximum amplifier stability any changes in the output circuitry should not be seen at the input.  There should be no feedback.


G4A08
G4A08:

In vacuum tubes, output signals can leak back to the input by the inter-electrode capacitance.  This will cause instability.  This instability can result in spurious emissions or rapid destruction of the tube by self oscillation.  Neutralization cancels the leaked signals.


G4A09
G4A09:

The type of feedback that can build up and cause destructive uncontrolled oscillation is positive feedback.  To cancel it out, negative feedback is used.


G4A10
G4A10:

The type of feedback that can build up and cause destructive uncontrolled oscillation is positive feedback.  To cancel it out, negative feedback is used.  Neutralization is the process of adding a controlled amount of negative feedback to a RF power amplifier circuit.


G4A11
G4A11:

In vacuum tubes, output signals can leak back to the input by the inter-electrode capacitance.  This will cause instability.  This instability can result in spurious emissions or rapid destruction of the tube by self oscillation.  Neutralization cancels the leaked signals.


G4B01
G4B01:

The horizontal channel is often used to sweep the electron beam regularly to allow the vertical channel to display a visual representation of a signal waveform.  An oscilloscope is a versatile piece of test equipment to have in a radio station.


G4B02
G4B02:

A signal tracer is a signal source that can be injected into a faulty receiver to allow a fault to be isolated to a particular stage.  It is commonly used to inject a test signal into the audio circuitry.  Then, the technician will listen to the speaker.  If the fault is not found in the audio portion of the circuitry, he will then work methodically toward the antenna end until the injected signal is not heard.


G4B03
G4B03:

This is a way to check out an antenna system without using your transmitter.  You need to use your receiver with a noise bridge.  In addition to measuring the impedance, a noise bridge can allow you to decide if the antenna needs to be made shorter or longer.


G4B04
G4B04:

In addition to measuring the impedance, a noise bridge can allow you to decide if the antenna needs to be made shorter or longer.


G4B05
G4B05:

With a monitoring oscilloscope, you can see what you are radiating.


G4B06
G4B06:

With a monitoring oscilloscope, you can see what you are radiating.  The output of the transmitter is the place to monitor RF.  If you monitor at other points you may be introducing distortion or extra signals.


G4B07
G4B07:

A field strength meter measures RF power.  To determine the approximate radiation of an antenna you must first transmit a test signal.  Then, you keep the meter fixed (or vice-versa) and rotate your antenna while transmitting.


G4B08
G4B08:

A field strength meter measures RF power.  To determine the approximate radiation of an antenna you must first transmit a test signal.  Then, you keep the meter fixed (or vice-versa) and rotate your antenna while transmitting.


G4B09
G4B09:

A field strength meter measures RF power.  To determine the approximate radiation of an antenna you must first transmit a test signal.  Then, you keep the meter fixed (or vice-versa) and rotate your antenna while transmitting.


G4B10
G4B10:

An increase of four times corresponds to a change of 6 dB which is one S-unit.  One dB is the minimum detectable audible change.  Press the NuTest "Formula" button for details of the dB system.


G4B11
G4B11:

An increase of four times corresponds to a change of 6 dB which is one S-unit.  One dB is the minimum detectable audible change.  Press the NuTest "Formula" button for details of the dB system.


G4C01
G4C01:

Bypass capacitors allow RF energy to leak to ground if they are used correctly.  They are often fitted on the output and AC lines of audio equipment.


G4C02
G4C02:

Modern telephones are prone to picking up RF interference.  You may have to install RFI filters on your telephone system.


G4C03
G4C03:

It will be clearly recognizable as speech, but it will be unintelligible.


G4C04
G4C04:

The "clicking" will occur when the "dits" and "dahs" are beginning or ending.  During a "dit" or "dah" the sound level on the public address system may alter or become distorted.


G4C05
G4C05:

Grounding is also important for safety reasons.


G4C06
G4C06:

This ground connection is 10 meters long which is a quarter wave on the 40 meter band, a half wave on the 20 meter band and one wavelength on the 10 meter band.  It will readily pick up RF energy.


G4C07
G4C07:

Adding a good ground connection will make no difference to the cost.  However, it will have several benefits.


G4C08
G4C08:

You want to avoid lengths that are resonant at the frequencies your station uses.  The ground connection should also have a low impedance.  Make sure your ground spike is at least 8 feet long and is placed in soil that is usually damp.  Ground connections should be made of thick copper braid.  One source of copper braid is coaxial cable.  Use the whole cable with the inner and outer conductors connected together.


G4C09
G4C09:

This is not true.  The more station equipment that can be grounded the better.  It could also be beneficial to ground your neighbor's audio and TV if they are designed with a suitable ground connection.


G4C10
G4C10:

For example, a ground connection to a station above ground floor level may be 30 feet long.  Thirty feet is 10 meters.  This is a quarter wave on the 40 meter band, a half wave on the 20 meter band and one wavelength on the 10 meter band.  It will readily pick up RF energy.  All equipment connected to it will be "live" with RF energy.


G4C11
G4C11:

The National Electrical code covers electrical wiring requirements.  It does not cover health limits.


G4D01
G4D01:

A speech processor improves intelligibility by allowing the average power of the transmitted signal to be increased.  An incorrectly used speech processor can cause a broad distorted signal.


G4D02
G4D02:

A speech processor increases the average power.  It does not increase the peak power.


G4D03
G4D03:

Peak envelope power (PEP) is the maximum power that the transmitter can output.  The term "PEV" stands for Peak Envelope Voltage.  This is half the peak to peak voltage measured on an oscilloscope.


G4D04
G4D04:

Using the equation:

Peak envelope power = (PEV x 0.707) x (PEV x 0.707) / Load.

Where PEV stands for Peak Envelope Voltage (half of the peak to peak voltage as measured on an oscilloscope).

We obtain (100 x 0.707) x (100 x 0.707) /50 = 99.7 which is close to 100 watts.


G4D05
G4D05:

Using the equation:

Peak envelope power = (PEV x 0.707) x (PEV x 0.707) / Load

Where PEV stands for Peak Envelope Voltage (half of the peak to peak voltage as measured on an oscilloscope).

We obtain (250 x 0.707) x (250 x 0.707) /50 = 625 watts (approximately).


G4D06
G4D06:

With an un-modulated carrier, the average power is the same as the peak power.


G4D07
G4D07:

If fuses were provided in the ground or return wires and the fuses blew, then the chassis of equipment could become live under certain fault conditions.  Note that over 240 volts can be present across the hot conductors of a four wire AC cord.


G4D08
G4D08:

The lowest AWG numbers are the thickest.  When used in household wiring situations, AWG number 14 wire is rated at 17 Amps maximum, continuous duty.  This leaves a safety margin.


G4D09
G4D09:

The lowest AWG numbers are the thickest.  When used in household wiring situations, AWG number 12 wire is rated at 23 Amps maximum, continuous duty.  This leaves a safety margin.


G4D10
G4D10:

When used in household wiring situations, AWG number 12 wire is rated at 23 Amps maximum, continuous duty.  This leaves a safety margin if a 20 Amp fuse or circuit-breaker is used.


G4D11
G4D11:

When used in household wiring situations, AWG number 14 wire is rated at 17 Amps maximum, continuous duty.  This leaves a safety margin if a 15 Amp fuse or circuit-breaker is used.


G4E01
G4E01:

This is how microwave ovens work.  The heating effect will be deep within the tissues and the resulting damage could be painless.


G4E02
G4E02:

You would not want you or any member of your family to be damaged by the heating effect of RF energy.  At VHF and UHF frequencies, it is possible for reflected signals to result in local hot spots of high RF energy.


G4E03
G4E03:

A dish antenna is designed to focus RF energy.  The RF field strength in front of the antenna can be high.  Your eyes are especially vulnerable to high RF field strengths.


G4E04
G4E04:

You would not want you or any member of your family to be damaged by the heating effect of RF energy.  At VHF and UHF frequencies, it is possible for reflected signals to result in local hot spots of high RF energy.


G4E05
G4E05:

A dish antenna is designed to focus RF energy.  The RF field strength in front of the antenna can be high.  Your eyes are especially vulnerable to high RF field strengths.


G4E06
G4E06:

Never underestimate the danger of high levels of RF energy.  Apart from the heating effect on tissues, it is also possible to get unpleasant skin burns from antennas, feeders and nearby metalwork.


G4E07
G4E07:

Put a fence around it and instruct your family to keep away.


G4E08
G4E08:

Never underestimate the danger of high levels of RF energy.  Apart from the heating effect on tissues, it is also possible to get unpleasant skin burns from antennas, feeders and nearby metalwork.  Also, NEVER look down a microwave feeder!


G4E09
G4E09:

A high gain antenna is designed to focus RF energy; the RF field strength can be high even at some distance. Your eyes are especially vulnerable to high RF field strengths.


G4E10
G4E10:

Never underestimate the danger of high levels of RF energy.  Apart from the heating effect on tissues, it is also possible to get unpleasant skin burns from antennas, feeders and nearby metalwork.


G4E11
G4E11:

The critical angle is related to ionospheric propagation.  It has nothing to do with body tissues.


G5A01
G5A01:

Impedance is the total opposition to AC caused by the combination of resistance in a circuit plus the reactance of the circuit.


G5A02
G5A02:

Capacitors and inductors are common components in radio circuits.  They both pass Alternating Current (AC) but they also oppose it.  A voltage drop occurs across them.


G5A03
G5A03:

Capacitors and inductors have reactance.  Reactance is an opposition to the flow of Alternating Current (AC).  Reactance is measured in Ohms.  It varies with the frequency of the Alternating Current.  An inductor has inductive reactance that increases with frequency.  Press the NuTest "Formula" button for more details.


G5A04
G5A04:

Capacitors and inductors have reactance.   Reactance is an opposition to the flow of Alternating Current (AC).  Reactance is measured in Ohms.  It varies with the frequency of the Alternating Current.  A capacitor has capacitive reactance that decreases with frequency.  Press the NuTest "Formula" button for more details.


G5A05
G5A05:

Capacitors and inductors have reactance.  Reactance is an opposition to the flow of Alternating Current (AC).  Reactance is measured in Ohms.  It varies with the frequency of the Alternating Current.  An inductor has inductive reactance that increases with frequency.  Press the NuTest "Formula" button for more details.


G5A06
G5A06:

Capacitors and inductors have reactance.   Reactance is an opposition to the flow of Alternating Current (AC).  Reactance is measured in Ohms.  It varies with the frequency of the Alternating Current.  A capacitor has capacitive reactance that decreases with frequency.  Press the NuTest "Formula" button for more details.


G5A07
G5A07:

Whenever a power source is connected to a load, maximum power transfer occurs when the two impedances are equal.  Making sure that the impedance of the source and the load are equal is called "matching".  It is important to match your antenna (the load) to your transceiver (the source) to obtain maximum power transfer of RF energy into the antenna.


G5A08
G5A08:

Whenever a power source is connected to a load, maximum power transfer occurs when the two impedances are equal.  Making sure that the impedance of the source and the load are equal is called "matching".  It is important to match your antenna (the load) to your transceiver (the source) to obtain maximum power transfer of RF energy into the antenna.


G5A09
G5A09:

Whenever a power source is connected to a load, maximum power transfer occurs when the two impedances are equal.  Making sure that the impedance of the source and the load are equal is called "matching".  It is important to match your antenna (the load) to your transceiver (the source) to obtain maximum power transfer of RF energy into the antenna.


G5A10
G5A10:

The same unit (the Ohm) is used to describe both resistance and impedance.


G5A11
G5A11:

The same unit (the Ohm) is used to describe both resistance and impedance.


G5B01
G5B01:

For an explanation of decibels (dB's), press the NuTest "Formula" button.


G5B02
G5B02:

For an explanation of decibels (dB's), press the NuTest "Formula" button.


G5B03
G5B03:

6 dB is 3 dB + 3 dB and each 3 dB is a doubling.  Press the NuTest "Formula" button for an explanation of the decibel measuring system.


G5B04
G5B04:

10 dB is a tenfold increase.  If the signal is ten times stronger than S9 then reducing it by a factor of 1500/150 = 10 will bring it down to S9.


G5B05
G5B05:

20 dB is a hundredfold increase.  If the signal is a hundred times stronger than S9 then reducing it by a factor of 1500/15 = 100 will bring it down to S9.


G5B06
G5B06:

In parallel connected resistors, the current flow will divide between the resistors.  In the case of two equal value resistors half the available current will flow through each resistor.


G5B07
G5B07:

The total current flowing will always be the sum of the individual currents in each branch.  To visualize this, think of water in a stream splitting up into several streams.


G5B08
G5B08:

Use the formula:  P = (E x E) /R to get (400 X 400)/800 = 200 watts.


G5B09
G5B09:

Use the formula:  P = E x I to get 12 x 0.2 - 2.4 watts.


G5B10
G5B10:

The question asks for "Watts."  This is a unit of power.  Use the formula:  P = (I x I) x R = 0.061 Watts.

Then, convert:  0.061 Watts = 61 milliwatts.


G5B11
G5B11:

A transformer can convert voltages.  The conversion ratio is directly related to the turns ratio.

Vs/Vp = Ns/Np and so Vs (the secondary voltage) = (Ns/Np) x Vp.

This gives Vs = (500/2250) = 26.7 volts

Press the NuTest "Formula" button for more details.


G5B12
G5B12:

In this case, we need to know the impedance transformation ratio of a transformer.  It is related to the turns ratio by the formula:  Np/Ns = square root of (Zp/Zs).

So we have Np/Ns = square root (600/4) = square root of (150) = 12.25

Press the NuTest "Formula" button for more details.


G5B13
G5B13:

We need to know the impedance transformation ratio of a transformer.  It is related to the turns ratio by the formula:  (Np/Ns) squared = Zp/Zs.

We have Zp/Zs = (24/1) squared = 576.

So the speaker impedance is 2000/576 = 3.47 which is approximately 3.5 Ohms.

Press the NuTest "Formula" button for more details.


G5B14
G5B14:

The Root Mean Squared (RMS) value is used in AC calculations to compensate for the fact the average voltage is not at the peak value for all the time.


G5B15
G5B15:

To convert the Root Mean Squared (RMS) value to peak voltage we multiply it by 1.414 to get 169.7.  However, the question asks for peak to peak voltage.  Therefore, we need to multiply by 2 to get 169.7 x 2 = 339.4 volts.


G5B16
G5B16:

To convert from peak voltage to Root Mean Squared (RMS) we divide 17 by 1.414 to get 12 Volts


G6A01
G6A01:

The temperature coefficient of a resistor may be small if it is designed not to change with temperature.  Some resistors are designed to have a large increase or decrease of resistance when the temperature changes.  These devices can be used to measure temperature.


G6A02
G6A02:

Electrolytic capacitors have relatively large values of capacitance for their size.  They contain liquids or gels.  With time, they can eventually dry out.


G6A03
G6A03:

Transient voltage spikes are caused by switching of AC power in other parts of your house, in other houses, by local industry or on the power distribution network.  Transient voltage spikes can destroy the rectifiers in a power supply.


G6A04
G6A04:

In a transformer, the primary winding is connected to the power source (usually your AC supply) and the secondary winding(s) to the load.


G6A05
G6A05:

The magnetizing current is wasted current that ultimately ends up as heat in the iron core of the transformer.


G6A06
G6A06:

Rectifiers are used in a power supply to convert the AC from the supply into DC that can be used by electronics equipment.  If the peak inverse voltage rating is exceeded (by a transient voltage spike, for example) then the rectifier will fail.


G6A07
G6A07:

Rectifiers are used in a power supply to convert the AC from the supply into DC that can be used by electronics equipment.  If the peak inverse voltage rating is exceeded (by a transient voltage spike, for example) then the rectifier will fail.  The rectifier will also heat up and fail if the average forward current rating is exceeded.


G6A08
G6A08:

The capacitor allows transient voltage spikes to leak harmlessly around the rectifier.  The resistance equalizes the reverse voltages across the rectifiers.


G6A09
G6A09:

In a full wave rectifier, both the negative and positive parts of the AC waveform are switched to positive pulses at twice the supply frequency.  The higher frequency makes it easier to filter the waveform to get pure DC.


G6A10
G6A10:

In a half wave rectifier, only half of the AC waveform is used.  Only the positive part of the AC waveform is used.  The negative portion is discarded.  The output waveform is more difficult to filter because it consists of a series of pulses at the supply frequency.


G6A11
G6A11:

Both the positive and negative parts of the AC waveform are used.


G7A01
G7A01:

A filter capacitor that is in good condition is capable of storing a lethal charge for many hours after the supply is switched off.  A power supply bleeder resistor is connected across the capacitor.  When the power supply is switched off, it discharges the capacitor in a few seconds.


G7A02
G7A02:

A filter capacitor that is in good condition is capable of storing a lethal charge for many hours after the supply is switched off.  A power supply bleeder resistor is connected across the capacitor.  When the power supply is switched off, it discharges the capacitor in a few seconds.


G7A03
G7A03:

A power supply filter network can be regarded as a low pass filter.


G7A04
G7A04:

This is because on one side there will be the supply voltage (which could be equal to the peak voltage if not much current is being drawn) and on the other side of the rectifier there will be the peak negative voltage.  This will occur once per cycle of the supply waveform.


G7A05
G7A05:

This is because on one side there will be the supply voltage (which could be equal to the peak voltage if not much current is being drawn) and on the other side of the rectifier there will be the peak negative voltage.  This will occur once per cycle of the supply waveform.


G7A06
G7A06:

All items in the path between transmitter and antenna should have the same impedance.  This satisfies the condition for maximum power transfer.


G7A07
G7A07:

The filter removes the unwanted side band and further suppresses the carrier.


G7A08
G7A08:

The balanced modulator mixes the audio signals with an RF carrier to produce a double side band suppressed carrier output.


G7A09
G7A09:

The mixer, as its name suggests, mixes a local oscillator signal with the incoming amplified signal.  This produces a difference frequency called the intermediate frequency (IF).  This is then amplified and detected to produce an audio signal.


G7A10
G7A10:

To detect a single side band signal, a reference signal at the position of the original carrier is required.  This is provided by a beat frequency oscillator (BFO).


G7A11
G7A11:

The IF amplifier gets the weak signals from the IF filter up to a level that the detector can handle.


G8A01
G8A01:

That is why it is called amplitude modulation!


G8A02
G8A02:

Phase modulation and frequency modulation are almost indistinguishable in practice.  It is the type of modulation circuit that is different.


G8A03
G8A03:

Frequency modulation is mainly used on the VHF and UHF bands.  This is due to its inherently greater bandwidth.


G8A04
G8A04:

Phase modulation and frequency modulation are almost indistinguishable in practice.  It is the type of modulation circuit that is different.


G8A05
G8A05:

Hence it is called Amplitude Modulation!


G8A06
G8A06:

Part of the suppression occurs in the balanced modulator and the rest (about 20 dB) occurs in the filter.


G8A07
G8A07:

If only side bands are transmitted, all the available transmitter power is used to convey speech information.  Therefore, a single side band transmission can legally be three times as powerful as an equivalent double side band AM signal.  All the legal power is focused into the single side band.  The other side band and the carrier wave are discarded.


G8A08
G8A08:

A Frequency Modulated signal can occupy a bandwidth of 10 - 20 kHz.  A phase modulated signal may occupy less space.  A double side band signal will occupy twice the required audio bandwidth giving 6 kHz.  A SSB transmission occupies only the required audio bandwidth of 3 kHz.


G8A09
G8A09:

The extra emissions from an incorrectly used SSB transmitter are called splatter.  If you cause splatter, you are advertising the fact that your transmitter is being used incorrectly or is faulty.


G8A10
G8A10:

The ALC meter measures the amount by which your audio is automatically being turned down to avoid splatter.


G8A11
G8A11:

Flat topping refers to the appearance of a badly overdriven SSB transmission on an oscilloscope.

Output of a correctly adjusted SSB transmitter;

Output of an overdriven SSB transmitter showing flat topping:


G8B01
G8B01:

It is the job of a receiver mixer to convert all the RF frequencies to a standard frequency (the Intermediate Frequency).  The IF can then be filtered, amplified and detected.


G8B02
G8B02:

When two signals are mixed, one result is a frequency corresponding to the difference between them.  In the question, the difference 14.255 - 13.800 gives 0.455 MHz which is 455 kHz, the required intermediate frequency.  However a signal on 13.345 MHz will also give a difference of 13.800 - 13.345 = 0.455 MHz which is 455 kHz.  So the receiver will also receive this unwanted image signal.  The solution is to filter the incoming RF before the mixer stage.  The ability of a receiver to reject image frequencies is vital.


G8B03
G8B03:

SSB transmitters do the signal generation and processing at a fixed frequency before it is mixed to obtain the required variable output frequency.


G8B04
G8B04:

In FM transmitters it is common to modulate an oscillator at low frequency and then raise the frequency by selecting harmonics in several stages.  This also has the effect of increasing the deviation and so the modulator deviation can be kept low to reduce distortion.


G8B05
G8B05:

FM has a greater bandwidth than AM.  An amateur narrow band FM signal has a bandwidth of about 16 kHz.  This is greater than the permitted bandwidth below 29.5 MHz.


G8B06
G8B06:

FM has a higher bandwidth than AM.

For a narrow band FM signal we can use:

Bandwidth = 2 (deviation + Maximum modulating frequency)

Giving 2 x (5 + 3) =16 kHz.

So an amateur narrow band FM signal has a bandwidth of about 16 kHz which is greater than the permitted bandwidth below 29.5 MHz


G8B07
G8B07:

In an FM transmitter the frequency deviation is increased at each stage of frequency multiplication.  In this question the frequency increase is 146.52/12.21 = 12 times.  So to end up with a 5 kHz deviation we need to start off at the oscillator with a deviation of 5 kHz / 12 = 416.7 Hz.


G8B08
G8B08:

As we increase the rate of information flow, the minimum bandwidth required increases.  This is the case no matter what communication mode is used.


G8B09
G8B09:

Anything that involves switching between two states is a digital transmission.


G8B10
G8B10:

The transmitter power is at a maximum and it is the frequency that is being shifted.


G8B11
G8B11:

This is another one of those amateur radio conventions.


G9A01
G9A01:

The broadening of bandwidth with increasing element diameter is taken to extremes in the discone antenna.  The single cone shaped element can have a frequency range of 10:1.


G9A02
G9A02:

Beam elements are about half a wavelength long; 33 feet is 10 meters.  At 14 MHz one wavelength is 20 meters.  You can also use the formula:  Driven Element Length = 472/(f in MHz) to get the required length.


G9A03
G9A03:

Beam elements are about half a wavelength long; 21 feet is 15 meters.  At 21.1 MHz one wavelength is 30 meters. You can also use the formula:  Driven Element Length = 472/(f in MHz) to get the required length.


G9A04
G9A04:

This question is tricky since 16.6 feet represents a half wavelength and looks correct.  However, we are finding the length of a Yagi reflector.  This is always slightly longer than the driven element.

Use the formula:  Reflector Element Length = 490/(f in MHz).

Reflector Element Length = 490/28.1 = 17.5 feet (approximately).


G9A05
G9A05:

In a Yagi the reflector is slightly longer than the driven element.  The director(s) are slightly shorter than the driven element.  If there are several directors they get progressively shorter with increasing distance from the driven element.  Exact dimensions for amateur construction of Yagi antennas can be found in many amateur radio publications.


G9A06
G9A06:

Generally, the more elements a Yagi antenna contains, the greater its gain will be.  However, each added element has less effect.  Eventually a law of diminishing returns applies.


G9A07
G9A07:

Wide spaced Yagi antennas are less practical at HF because they are difficult to construct.


G9A08
G9A08:

Anything that reduces the effects of overcrowding on this band is a good idea!


G9A09
G9A09:

Front to back ratios of 15 - 25 dB's are common with Yagi antennas.  A good front to back ratio means that less of your RF power is wasted going in the opposite direction to that intended.


G9A10
G9A10:

The main lobe is where the action is!  Your transmitted power will be focused there.


G9A11
G9A11:

Exact dimensions for amateur construction of Yagi antennas can be found in many amateur radio publications.  Generally, the more elements a Yagi antenna contains, the greater its gain will be.  However, each added element has less effect.  Eventually a law of diminishing returns applies.  At UHF and VHF it is important that construction is accurate; inaccuracies of 1/8 inches can affect antenna performance at these frequencies.


G9B01
G9B01:

Use the equation:  Total element length (feet) = 1005/(frequency MHz).

This gives 1005/21.4 = 46.9 feet.

So, each side is 46.9/4 = 11.7 feet.

Press the NuTest "Formula" button for more details.


G9B02
G9B02:

Use the equation:  Total element length (feet) = 1005/(frequency MHz).

This gives 1005/14.3 = 70.27 feet.

So, each side is 70.27/4 = 17.6 feet.

Press the NuTest "Formula" button for more details.


G9B03
G9B03:

The reflector is slightly longer than the driven element.

Use the equation:  Total element length (feet) = 1030/(frequency MHz).

This gives 1030/29.6 = 34.8 feet.

So, each side is 34.8/4 = 8.7 feet.

Press the NuTest "Formula" button for more details.


G9B04
G9B04:

Use the equation:  Total element length (feet) = 1005/(frequency MHz).

This gives 1005/28.7 = 35 feet.

So, each side is 35/3 = 11.7 feet.

Press the NuTest "Formula" button for more details.


G9B05
G9B05:

Use the equation:  Total element length (feet) = 1005/(frequency MHz).

This gives 1005/24.9 = 40.36 feet.

So, each side is 40.36/3 = 13.45 feet.

Press the NuTest "Formula" button for more details.


G9B06
G9B06:

Use the equation:  Total element length (feet) = 1030/(frequency MHz).

This gives 1030/14.1 = 73 feet.

So, each side is 73/3 = 24.35 feet.

Press the NuTest "Formula" button for more details.


G9B07
G9B07:

They are also less affected by being erected at low heights.


G9B08
G9B08:

The "quad" is a good DX antenna for the HF bands.


G9B09
G9B09:

Moving the feed point like this is equivalent to rotating the whole antenna around its horizontal axis by 90 degrees.


G9B10
G9B10:

A good front to back ratio means that less of your RF power is wasted going on the opposite direction to that intended.  A delta loop with no reflector or director will have a front to back ratio of 0 dB.  In other words, equal power will be radiated in two directions.


G9B11
G9B11:

The radiation pattern will have two main lobes in opposite directions.


G9C01
G9C01:

The whole of the length of wire radiates RF energy right from the matching network output.


G9C02
G9C02:

A random wire element will most likely NOT be resonant at the operating frequency.  It will be reactive and the impedance may not be anywhere near 50 ohms.  This is fine so long as an antenna matching unit is used.


G9C03
G9C03:

This is because the antenna will be radiating along its entire length from the output of the antenna matching unit.  Some of the antenna radiation will be in the station and could get into the audio circuits of your transceiver where it may be detected.


G9C04
G9C04:

A ground plane antenna on a flat surface has an impedance of around 35 Ohms.  This is not a good match to a 50 ohm feedline.  Sloping the radials gives a better match.


G9C05
G9C05:

A ground plane antenna on a flat surface has an impedance of around 35 Ohms.  This is not a good match to a 50 ohm feedline.  Sloping the radials gives a better match.


G9C06
G9C06:

Maximum radiation is at right angles to the direction of the antenna.  Little or no RF is radiated in the direction of the antenna.


G9C07
G9C07:

On HF it is not easy to get an antenna high enough to completely eliminate effects of reflections from the ground.  Excellent results can still be obtained at less than optimum height.


G9C08
G9C08:

This is a sort of Yagi with one director.


G9C09
G9C09:

This is a sort of Yagi with a reflector.


G9C10
G9C10:

The wires can be buried just a few inches deep in a lawn.  This can be done by cutting slots with a lawn edging tool.  The radials should be soldered where they meet.  Generally, the shorter the antenna the better the ground plane system should be.


G9C11
G9C11:

This question has been withdrawn.


G9D01
G9D01:

Parallel conductor line has very low losses.


G9D02
G9D02:

A 50 Ohm feed line is preferred because this is closer to the feed impedance of most antennas as well as the output impedance of transceivers.


G9D03
G9D03:

You will need to use an impedance matching network between your transceiver and this type of feedline.


G9D04
G9D04:

Some antennas present an impedance of 50 ohms at the feed point.  Others do not.  Therefore, a matching system has to constructed at the feed point.  You will hear terms such as gamma match and T-match.  These are devices for matching feed lines to antenna feed points.


G9D05
G9D05:

Some antennas present an impedance of 50 ohms at the feed point.  Others do not.  Therefore, a matching system has to constructed at the feed point.  You will hear terms such as gamma match and T-match.  These are devices for matching feed lines to antenna feed points.


G9D06
G9D06:

The matching network would also match the 50 ohm output impedance of the transceiver to the 300 ohm feedline impedance.


G9D07
G9D07:

In feed lines, the losses always increase as the signal frequency increases.


G9D08
G9D08:

The following are some feedline losses for different types of coaxial cable operating at a frequency of 50 MHz.  All are given as dB of loss per 100 feet of cable.

RG-213	1.5 dB

RG-58	3.0 dB

RG-59	2.4 dB

RG-174	5.5 dB


G9D09
G9D09:

The standing wave ratio is found by taking the ratio:  (higher impedance) / (lower impedance).


G9D10
G9D10:

The standing wave ratio is found by taking the ratio:  (higher impedance) / (lower impedance).


G9D11
G9D11:

The standing wave ratio is found by taking the ratio:  (higher impedance) / (lower impedance).