Ariel I created a notebook specifically for mistakes, including those I frequently made and those that looked similar but were easily confused. I would regularly review this notebook, for example, my notes from that time:
Q Concise Language
QRP reduces power, QRO increases power – QRP expert, so QRO newbie.
QRQ accelerates speed, QRS slows down speed – QRQ is fast, while QRS is slow.
QRL? Is anyone there? QRL, are you there? I'm busy.
QRM - Interference from another station
QRN - Interference from atmospheric electrical activity
QRT - Please stop – Please someone
QRU? Is there anything else? QRU is okay.
QRV is ready – ✌️
QRZ Who is calling me – Prepare to send a QSL card to qrz.com
QSK gap reception
QSP transmits message to xx radio station – Passed
QSX listens attentively – Q trusts QSX.
QSY changing frequency – Y is an antenna.
QSA signal strength
The QSB signal is fading – you idiot.
The QSD technique has a flaw – your SD.
Communicated with QSO via xxx.
Frequency usage
There's no pattern; you need to remember the numbers.
7 MHz LSB occupies the frequency range of 7030-7200
14 MHz USB occupies the frequency range of 14100-14350
18 MHz USB occupies the frequency range of 18.1105-18168
21 MHz USB occupies the frequency range of 21125–21450, excluding 21.1495–21.1505.
24 MHz USB occupies the frequency range of 24.9305 - 24.99
29 MHz USB occupies the 28.3-29.3 frequency range.
29 MHz FM occupies the frequency range of 29.51–29.7
The 28 MHz band should not occupy the 29.3-29.51 range (as stated in the question... it shouldn't occupy this range, actually this range is for satellites; the question is missing a comma).
Launch category
Since rote memorization doesn't work, we need to understand what each letter represents:
First letter: F-FM tuning, J-single-sideband, A-double-sideband, G-tuning
Second letter: 1 - No subcarrier; 2 - Subcarrier; 3 - Single channel
Third letter:
A - Manual telegraph
B - Automatic telegraph
E - Voice broadcast
CW A1A, double-sided A, no subcarrier, manual Morse code A, so find the last letter that is A.
SSB J3E, SSB (Single-Sideband) receiver, single-sideband radio, voice transmission over E, therefore J3E.
RTTY F2B, automatic, so the last letter is B, then tune to frequency F, with 2 carriers, therefore F2B.
PSK31 G2B, automatic, so the last letter is B, followed by the tuning frequency G, resulting in G2B.
FM F3E, frequency-modulated FM, so look for F as the prefix, a single channel, and voice E.
RC circuit
Suddenly being powered on, meaning a gradual increase in power; suddenly losing power, meaning a gradual decrease in power.
The RC series suddenly becomes energized: — There's a capacitor, so the entire circuit initially has power and then loses it. Finally, the capacitor has voltage but no current, while everything else is off.
- C Voltage 0-->U, current 0->U/R>0
- R voltage 0->U-->0, Current 0->U/R>0
RC series suddenly loses power: — In the instant when it abruptly disconnects, the capacitor will suddenly become a battery, but eventually everyone will gradually run out of power.
- C Voltage U-->0, Current 0->U/R>0
- R voltage U-->0, Current U/R -->0
The RL series suddenly became energized: – The inductor provides a path for current, so the entire circuit gradually becomes energized, but the inductor acts as a conductor and eventually has no voltage.
- L Voltage 0->U-->0, Current 0-->U/R
- R voltage 0-->U, current 0-->U/R
RL suddenly loses power: – Gradually losing power.
- L Voltage U-->0, the rest don't matter; there is no question bank.
Distortion series
Frequency distortion, changes in amplitude ratio.
Phase distortion, delay difference changes
Non-linear distortion, resulting in new quantities.
Calculation problems
1/4 wavelength, phased array antenna: 48.8/f – select 48.8 if the frequency is within the 4 band, otherwise select 71.3.
Half-wave dipole antenna: 71.3/f
When the transmit power is 20 dBW, the reading is S9. When the transmit power is 0.098 – select 98 if it contains a "9", otherwise select 156.
When the transmit power is 10 dBW, the reading is S8. When the transmit power is 0.156
A hobby radio station, operating voltage DC 13.8V, current consumption 0.091 – find the second smallest number.
A small amateur radio station, operating at an AC voltage of 220 volts and a current of 0.0057 – find the second smallest number.
A small amateur radio station, with an FM transmission method, has a radio frequency output carrier power of N watts. Power consumption: 0.0000035 – find the one with the most 0s.
Frontend bandwidth vs. mirror suppression ratio
Deciding on a receiver that can tolerate interference from strong signals with frequencies significantly different from its operating frequency, particularly in terms of front-end bandwidth.
The receiver's rejection ratio and operating frequency are twice apart, at a frequency in the mid-band: The image suppression ratio is.
1/4 wavelength
In a specific orientation, the antenna has a horizontal dipole with a main radiating element, and the total length of the resonator is a fractional odd multiple of 1/2.
The dipole antenna's two arms are at their optimal positions, achieving maximum gain, with a factor of 1/2.
The necessary and sufficient conditions for a dipole antenna to resonate with a given frequency are: 1/2 integer multiple.
A quarter wavelength odd multiple, will definitely have the best effect.
For a symmetrical half-wave oscillator, each arm is 1/4 of the wavelength.
Constant; Unchanging
The signal amplitude remains constant and unchanging; select the option that does not include the word "amplitude".
The carrier frequency amplitude remains constant and unchanged; it includes the terms "carrier frequency" and "amplitude of two words." It refers to AM (Amplitude Modulation).
The period remains constant and unchanged; select PM.
Sectioning
The commonly referred to 40-meter amateur band, with its frequency range in ITU Region 1, 2, and 3, and its usage status for amateur and satellite amateur operations, is: 232 dedicated.
The International Telecommunication Union (ITU) has three regions, with particular attention being paid to Region 2, which covers the Americas.
Our CQ 23 24 27
Which of China's ITU selections has the most entries?
The Huangyan Island CQ zone has the numbers 27, 24, and 24. Dongsha and Diaoyu Islands are located next to Taiwan, while Huangyan Island is further away, so the numbers for Dongsha and Diaoyu Islands are the same, but the numbers for Huangyan Island are different. This applies to ITU as well.
Huangyan Island, ITU Zone 50 44 44
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