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PIN Diode RF Attenuation

Microwave Switch

What is used to control the attenuation of RF signals by a PIN diode? A. Forward DC bias current B. A sub-harmonic pump signal C. Reverse voltage larger than the RF signal D. Capacitance of an RF coupling capacitor [E6B11] This question from the new Amateur Extra question pool dives head first into the operation … Read more

What is a Telecommand Station?

What is a telecommand station in the amateur satellite service?

What is a telecommand station in the amateur satellite service? A. An amateur station located on the Earth’s surface for communication with other Earth stations by means of Earth satellitesB. An amateur station that transmits communications to initiate, modify or terminate functions of a space stationC. An amateur station located more than 50 km above … Read more

Amateur Radio Exam Passing Score

Amateur Radio Exam Passing Score

Part of the Amateur Extra exam is meant to prepare you for the possibility of becoming a VEC or Volunteer Exam Coordinator, and so they want you to know and understand some of the mechanics of the exams themselves. So, here’s one: What is the minimum passing score on amateur operator license examinations? A. Minimum … Read more

Amateur Extra: Crystal Oscillator Frequency

Crystal Oscillator

Which of the following must be done to insure that a crystal oscillator provides the frequency specified by the crystal manufacturer? A. Provide the crystal with a specified parallel inductanceB. Provide the crystal with a specified parallel capacitanceC. Bias the crystal at a specified voltageD. Bias the crystal at a specified current A crystal oscillator … Read more

Sporadic E Propagation : Amateur Extra

Sporadic E Propagation

At what time of year is Sporadic E propagation most likely to occur? A. Around the solstices, especially the summer solsticeB. Around the solstices, especially the winter solsticeC. Around the equinoxes, especially the spring equinoxD. Around the equinoxes, especially the fall equinox Sporadic E Propagation refers to the phenomena where radio signals bounce off of … Read more

Amateur Extra: Gray Code

Gray Code

What is an advantage of Gray code in digital communications where symbols are transmitted as multiple bits? A. It increases security B. It has more possible states than simple binary C. It has more resolution than simple binary D. It facilitates error detection Firstly, what the heck is “Gray code” anyway? The reflected binary code … Read more

Amateur Extra: Circular Polarization

Circular Polarization

What is meant by circularly polarized electromagnetic waves? A. Waves with an electric field bent into a circular shapeB. Waves with a rotating electric fieldC. Waves that circle the EarthD. Waves produced by a loop antenna To answer this we need to understand what’s going on inside an electromagnetic (or EM) wave.  In an EM … Read more

Amateur Extra: Variable-Length Coding

PSK Traces

Which of the following HF digital modes uses variable-length coding for bandwidth efficiency? A. RTTYB. PACTORC. MT63D. PSK31 Now, I guess this answers my question about last weeks Extra question. Mainly why is it important.  It’s important because it does matter in transmission efficiency.  So which mode would be a good and efficient method of … Read more

Amateur Extra: Using ASCII Code

What is one advantage of using ASCII code for data communications? A. It includes built in error correction featuresB. It contains fewer information bits per character than any other codeC. It is possible to transmit both upper and lower case textD. It uses one character as a shift code to send numeric and special characters … Read more