CLASS B - ELEMENT VI

Which of the following is a Yagi antenna design variable that could be adjusted to optimize forward gain, front-to-back ratio, or SWR bandwidth?

• the physical length of the boom

• the number of elements on the boom

• the spacing of each element along the boom

• the physical length of the boom, the number of elements on the boom, the spacing of each element along the boom

What is an advantage of downward sloping radials on a quarter wave ground-plane antenna?

• They bring the feed-point impedance closer to 50 ohms

• They increase the antenna's height

• They reduce the antenna's bandwidth

• They increase the antenna's weight

When the polarity of voltage is incorrect, the diode acts as a very high resistance that does not allow conduction and is said to be in what condition?

• Forward bias

• Reverse bias

• Breakdown

• Avalanche

What is meant by the term ROM?

• Read Only Memory

• Random Output Memory

• Read Operation Memory

• Reverse Output Module

What is meant when memory is characterized as 'non-volatile'?

• The stored information is lost when power is removed

• The stored information is maintained even if power is removed
  

• The memory is resistant to changes

• The memory is volatile at high temperatures

What is the primary purpose of antenna traps?

• To reduce noise

• To permit multiband operation

• To improve signal strength

• To prevent interference

In order to emit light, an L.E.D (light emitting diode) must be _______ .

• reverse biased

• forward biased

• unbiased

• in series with a resistor

The simple and lowly neon lamp technology has enjoyed a revival in recent years with the invention of ______ .

• LED bulbs

• Plasma television

• Fiber optics

• Laser diodes

In what values are RF feed line losses usually expressed?

• dB per foot

• dB per 100 ft

• dB per meter

• dB per km

In general we expect a circuit composed of common emitter NPN audio transistor amplifier stages to have _______ .

• positive ground

• negative ground

• floating ground

• no ground