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General: Quad Antennas

Quad Antenna

Approximately how long is each side of the reflector element of a quad antenna? A. Slightly less than 1/4 wavelength B. Slightly more than 1/4 wavelength C. Slightly less than 1/2 wavelength D. Slightly more than 1/2 wavelength So lets look at what a “quad antenna” entails.  As you might have guessed from the name, … 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

General: Sine Wave Oscillators

RC phase shift oscillator

What are the basic components of virtually all sine wave oscillators? A. An amplifier and a dividerB. A frequency multiplier and a mixerC. A circulator and a filter operating in a feed-forward loopD. A filter and an amplifier operating in a feedback loop To answer this question, lets look at what makes up a sine … 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

General: Uses For An Antenna Analyzer

What is a use for an antenna analyzer other than measuring the SWR of an antenna system? A. Measuring the front to back ratio of an antennaB. Measuring the turns ratio of a power transformerC. Determining the impedance of an unknown or unmarked coaxial cableD. Determining the gain of a directional antenna Well, you’re not … Read more

General: Peak Inverse Voltage

Halfwave rectifier

What is the peak-inverse-voltage across the rectifier in a half-wave power supply? A. One-half the normal peak output voltage of the power supplyB. One-half the normal output voltage of the power supplyC. Equal to the normal output voltage of the power supplyD. Two times the normal peak output voltage of the power supply [G7A04] To … Read more