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HAM Radio 3.2
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Ham Radio Version 3.2 (Chestnut CD-ROMs)(1993).ISO
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tec15
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tec5.dat
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1991-08-01
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148D-7.2 B 8-17 Depends on where you work |Good for aligning receivers
What is an RF signal generator commonly used for?
A. Measuring RF signal amplitude
B. Aligning receiver tuned circuits
C. Adjusting the transmitter impedance-matching network
D. Measuring transmission line impedance
*
149D-8-1.1 D 8-17 A reflectometer is like a directional|wattmeter, but calibrated in SWR. A|wattmeter may also be a reflectometer
What is a reflectometer?
A. An instrument used to measure signals reflected from the
ionosphere
B. An instrument used to measure radiation resistance
C. An instrument used to measure transmission-line impedance
D. An instrument used to measure standing wave ratio
*
150D-8-1.2 D 8-17 A reflectometer can indicate|an impedance mismatch in the|antenna/feed system
What is the device that can indicate an impedance mismatch
in an antenna system?
A. A field-strength meter
B. A set of lecher wires
C. A wavemeter
D. A reflectometer
*
151D-8-2.1 A 8-17 The answer to this question is A|A small distance back from the |antenna might actually be better
For best accuracy when adjusting the impedance match
between an antenna and feed line, where should the
match-indicating device be inserted?
A. At the antenna feed point
B. At the transmitter
C. At the midpoint of the feed line
D. Anywhere along the feed line
*
152D-8-2.2 C 8-17 Transmission line losses reduce SWR |readings with long cables. The most|valid reading would be at the antenna
Where should a reflectometer be inserted into a long antenna
transmission line in order to obtain the most valid standing
wave ratio indication?
A. At any quarter-wavelength interval along the transmission
line
B. At the receiver end
C. At the antenna end
D. At any even half-wavelength interval along the transmission
line
*
153D-9.1 D 8-18 A dummy load, used as a dummy antenna|during filter alignment will keep the|transmitter from causing interference
When adjusting a transmitter filter circuit, what device is
connected to the transmitter output?
A. A multimeter
B. A set of Litz wires
C. A receiver
D. A dummy antenna
*
154D-9.2 B 8-18 A dummy antenna is a nonradiating load|used to keep transmitter testing from |causing interference
What is a dummy antenna?
A. An isotropic radiator
B. A nonradiating load for a transmitter
C. An antenna used as a reference for gain measurements
D. The image of an antenna, located below ground
*
155D-9.3 C 8-18 Reactances do not dissipate power &|would cause a high SWR in the dummy|antenna, so they are not used
Of what materials may a dummy antenna be made?
A. A wire-wound resistor
B. A diode and resistor combination
C. A noninductive resistor
D. A coil and capacitor combination
*
156D-9.4 B 8-18 A dummy load used |as a dummy antenna
What station accessory is used in place of an antenna during
transmitter tests so that no signal is radiated?
A. A Transmatch
B. A dummy antenna
C. A low-pass filter
D. A decoupling resistor
*
157D-9.5 A 8-18 A nonradiating load used for |off-the-air transmitter testing
What is the purpose of a dummy load?
A. To allow off-the-air transmitter testing
B. To reduce output power for QRP operation
C. To give comparative signal reports
D. To allow Transmatch tuning without causing interference
*
158D-9.6 A 8-18 100 Watts is 100 watts
How many watts should a dummy load for use with a 100-watt
emission J3E transmitter with 50 ohm output be able to dissipate?
A. A minimum of 100 watts continuous
B. A minimum of 141 watts continuous
C. A minimum of 175 watts continuous
D. A minimum of 200 watts continuous
*
159D-10.1 C 8-18 S-meters are found on amateur |receivers and indicated Signal|strength
What is an S-meter?
A. A meter used to measure sideband suppression
B. A meter used to measure spurious emissions from
a transmitter
C. A meter used to measure relative signal strength
in a receiver
D. A meter used to measure solar flux
*
160D-10.2 A 8-18 S-meters are found on amateur |receivers and indicated Signal|strength
A meter that is used to measure relative signal strength in a
receiver is known as what?
A. An S-meter
B. An RST-meter
C. A signal deviation meter
D. An SSB meter
*
161D-11-1.1B 8-18 Large amounts of RF energy in a|Microwave Oven heats the food &|cooks it
Large amounts of RF energy may cause damage to body tissue,
depending on the wavelength of the signal, the energy density
of the RF field, and other factors. How does RF energy effect
body tissue?
A. It causes radiation poisonings
B. It heats the tissue
C. It cools the tissue
D. It produces genetic changes in the tissue
*
162D-11-1.2A 8-18 The eyes
Which body organ is most susceptible to damage from the heating
effects of radio frequency radiation?
A. Eyes
B. Hands
C. Heart
D. Liver
*
163D-11-2.1D 8-19 ANSI
Scientists have devoted a great deal of effort to determine
safe RF exposure limits. What organization has established
an RF protection guide?
A. The Institute of Electrical and Electronics Engineers
B. The American Radio Relay League
C. The Environmental Protection Agency
D. The American National Standards Institute
*
164D-11-2.2B 8-19 Sets how much RF exposure is ok
What is the purpose of the ANSI RF protection guide?
A. It protects you from unscrupulous radio dealers
B. It sets RF exposure limits under certain circumstances
C. It sets transmitter power limits
D. It sets antenna height requirements
*
165D-11-2.3B 8-19 VHF
The American National Standards Institute RF protection
guide sets RF exposure limits under certain circumstances.
In what frequency range is the maximum exposure level the
most stringent (lowest)?
A. 3 to 30 MHz
B. 30 to 300 MHz
C. 300 to 3000 MHz
D. Above 1.5 GHz
*
166D-11-2.4D 8-19 Wavelengths at VHF are close|to whole-body resonance
The American National Standards Institute RF protection
guide sets RF exposure limits under certain circumstances.
Why is the maximum exposure level the most stringent (lowest)
in the ranges between 30 MHz and 300 MHz?
A. There are fewer transmitters operating in this frequency range
B. There are more transmitters operating in this frequency range
C. Most transmissions in this frequency range are for an
extended time
D. Human body lengths are close to whole-body resonance in
that range
*
167D-11-2.5B 8-19 Most hand-helds are around|Five Watts on high power
The American National Standards Institute RF protection guide
sets RF exposure limits under certain circumstances. What is
the maximum safe power output to the antenna terminal of a
hand-held VHF or UHF radio, as set by this RF protection guide?
A. 125 milliwatts
B. 7 watts
C. 10 watts
D. 25 watts
*
168D-11-3.1C 8-19 Do you use your microwave|oven with the door open? |Replace the shielding
After you make internal tuning adjustments to your VHF power
amplifier, what should you do before you turn the amplifier on?
A. Remove all amplifier shielding to ensure maximum cooling
B. Connect a noise bridge to eliminate any interference
C. Be certain all amplifier shielding is fastened in place
D. Be certain no antenna is attached so that you will not cause
any interference
*
169E-1-1.1 D 3-6 Resistance is the opposition(resists)|to the flow of current in a circuit |that does not contain reactance
What is meant by the term resistance?
A. The opposition to the flow of current in an electric
circuit containing inductance
B. The opposition to the flow of current in an electric
circuit containing capacitance
C. The opposition to the flow of current in an electric
circuit containing reactance
D. The opposition to the flow of current in an electric
circuit that does not contain reactance
*
170E-1-2.1 A 3-6 The basic unit of resistance is|the ohm and the symbol is Ω
What is an ohm?
A. The basic unit of resistance
B. The basic unit of capacitance
C. The basic unit of inductance
D. The basic unit of admittance
*
171E-1-2.2 D 3-6 The basic unit of resistance is|the ohm and the symbol is Ω
What is the unit measurement of resistance?
A. Volt
B. Ampere
C. Joule
D. Ohm
*
172E-1-3.1 B 3-9 Resistors in series add directly |Rt = R1 + R2 + R3... For two equal|value resistors, Rt = 2*R1 or 2*R2
Two equal-value resistors are connected in series. How does
the total resistance of this combination compare with the
value of either resistor by itself?
A. The total resistance is half the value of either resistor
B. The total resistance is twice the value of either resistor
C. The total resistance is the same as the value of either
resistor
D. The total resistance is the square of the value of either
resistor
*
173E-1-3.2 D 3-9 Resistors in series add directly|Rt = R1 + R2 + R3...
How does the total resistance of a string of series-connected
resistors compare to the values of the individual resistors?
A. The total resistance is the square of the sum of all the
individual resistor values
B. The total resistance is the square root of the sum of the
individual resistor values
C. The total resistance is the sum of the squares of the
individual resistor values
D. The total resistance is the sum of all the individual
resistance values
*
174E-1-4.1 B 3-9 In general 1/Rt = 1/R1 + 1/R2 + 1/R3..|For two resistors Rt = (R1*R2)/(R1+R2)|If R1 = R2 then Rt = R1/2 or Rt = R2/2
Two equal-value resistors are connected in parallel. How does
the total resistance of this combination compare with the value
of either resistor by itself?
A. The total resistance is twice the value of either resistor
B. The total resistance is half the value of either resistor
C. The total resistance is the square of the value of either
resistor
D. The total resistance is the same as the value of either
resistor
*
175E-1-4.2 C 3-9 For two resistors Rt = (R1*R2)/(R1+R2)|Less than the smallest-value resistor
How does the total resistance of a string of parallel-connected
resistors compare to the values of the individual resistors?
A. The total resistance is the square of the sum of the resistor
values
B. The total resistance is more than the highest-value resistor
in the combination
C. The total resistance is less than the smallest-value resistor
in the combination
D. The total resistance is the same as the highest-value resistor
in the combination
*
176E-2.1 D 3-8 A mathematical relationship between |voltage, current and resistance in a|circuit. It is E = I * R
What is Ohm's law?
A. A mathematical relationship between resistance, voltage and
power in a circuit
B. A mathematical relationship between current, resistance and
power in a circuit
C. A mathematical relationship between current, voltage and
power in a circuit
D. A mathematical relationship between resistance, current and
applied voltage in a circuit
*
177E-2.2 A 3-8 I = E / R
How is the current in a dc circuit calculated when the voltage
and resistance are known?
A. I = E / R
B. P = I x E
C. I = R x E
D. I = E x R
*
178E-2.3 C 3-8 R = E / I |R = 12/.25|R = 48 Ω
What is the input resistance of a load when a 12-volt battery
supplies 0.25 amperes to it?
A. 0.02 ohms
B. 3 ohms
C. 48 ohms
D. 480 ohms
*
179E-2.4 D 3-10 Electromotive force, EMF is|another term for voltage
The product of the current and what force gives the electrical
power in a circuit?
A. Magnetomotive force
B. Centripetal force
C. Electrochemical force
D. Electromotive force
*
180E-2.5 B 3-8 R = E / I |R = 12/.15|R = 80 Ω
What is the input resistance of a load when a 12-volt battery
supplies 0. 15 amperes to it?
A. 8 ohms
B. 80 ohms
C. 100 ohms
D. 800 ohms
*
181E-2.6 D 3-8 I = E / R |I = 120/4700|I = .026 A
When 120 volts is measured across a 4700-ohm resistor,
approximately how much current is flowing through it?
A. 39 amperes
B. 3.9 amperes
C. 0.26 ampere
D. 0.026 ampere
*
182E-2.7 D 3-8 I = E / R |I = 120/47000|I = .0026 A
When 120 volts is measured across a 47000-ohm resistor,
approximately how much current is flowing through it?
A. 392 A
B. 39.2 A
C. 26 mA
D. 2.6 mA
*
183E-2.8 A 3-8 I = E / R |I = 12/4700 |I = .0026 A
When 12 volts is measured across a 4700-ohm resistor,
approximately how much current is flowing through it?
A. 2.6 mA
B. 26 mA
C. 39.2 A
D. 392 A
*
184E-2.9 A 3-8 I = E / R |I = 12/47000|I = 2.6E-4
When 12 volts is measured across a 47000-ohm resistor,
approximately how much current is flowing through it?
A. 255 µA
B. 255 mA
C. 3917 mA
D. 3917 A
*