Transmitters and Receivers

True/False
Indicate whether the statement is true or false.

____	1.	A Tx crystal that is 75.4 Mhz is close enough to an Rx crystal labelled 74.5 to allow the transmitter to work with the receiver.

____	2.	Resonance is a factor that only occurs in electronics

____	3.	An antenna is a transducer designed to transmit or receive electromagnetic waves.

____	4.	In order for a signal to be transmitted, received, and used, it often must be amplified.

____	5.	RF waves radiate out from most antennas in a circular wave similar to those created when you drop a rock into a pond.

____	6.	When building a robot, it is a good idea to take the flimsy wire of the Rx antenna and wrap it around a support beam and tape it tight to keep it from getting caught in the wheels.

Multiple Choice
Identify the choice that best completes the statement or answers the question.

____	7.	The entire electromagnetic set of frequencies is referred to as the _________________      __________________.
a.	electromagnetic spectrum	c.	electromagnetic band	
b.	electromagnetic frequencies	d.	electric frequency waves	

____	8.	Electromagnetic waves most often take the shape known as a ____________      _______.
a.	square wave	c.	sinusoidal wave	
b.	frequency wave	d.	electromagnetic frequency	

____	9.	The faster a wave oscillates, the ___________ the wavelength.
a.	longer	c.	flatter	
b.	shorter	d.	sharper	

____	10.	The most popular type of antenna is the _____________ antenna
a.	passive	c.	dual polar	
b.	active	d.	dish	

____	11.	If a signal from a 27.119 Mhz Tx crystal is received and sent down the system to an amp and then sent to a 27.695 Mhz Rx crystal, that crystal will ________________________________.
a.	not oscillate because the antenna will not pick up the signal.	c.	oscillate slightly since the signal is close, causing the robot to react in a jerky motion.	
b.	oscillate since it is close enough to the Tx frequency.	d.	not oscillate and the signal stops there.	

____	12.	Frequency equals one divided by time.         
One is a representation of one  _______________________.
a.	pulse	c.	minute	
b.	cycle	d.	second	

Matching

a.	Remote	e.	Propagate	
b.	Frequency	f.	Hertz	
c.	Antenna	g.	Amplitude	
d.	Crystal	h.	Spectrum	

____	13.	A unit of frequency equal to one cycle per second

____	14.	A controller acting on a robot from a distance 

____	15.	A component  used in electronics as a frequency-determining element.

____	16.	A metallic device (as a rod or wire) for radiating or receiving radio waves

____	17.	The extent of a vibratory movement measured from the mean position to an extreme in one direction, then back through the mean to an extreme in the oposite direction.

____	18.	To transmit (as sound or light) through a medium (as air or water)

____	19.	The entire range of wavelengths or frequencies of electromagnetic radiation extending from gamma rays to the longest radio waves and including visible light

____	20.	The number of repetitions of a periodic process in a unit of time: as the number of complete oscillations per second of energy (as electromagnetic radiation) in the form of waves.

Transmitters and Receivers
Answer Section

TRUE/FALSE

	1.	ANS:	F	PTS:	1

	2.	ANS:	F	PTS:	1

	3.	ANS:	T	PTS:	1

	4.	ANS:	T	PTS:	1

	5.	ANS:	T	PTS:	1

	6.	ANS:	F	PTS:	1

MULTIPLE CHOICE

	7.	ANS:	A	PTS:	1

	8.	ANS:	C	PTS:	1

	9.	ANS:	B	PTS:	1

	10.	ANS:	A	PTS:	1

	11.	ANS:	D	PTS:	1

	12.	ANS:	B	PTS:	1

MATCHING

	13.	ANS:	F	PTS:	1

	14.	ANS:	A	PTS:	1

	15.	ANS:	D	PTS:	1

	16.	ANS:	C	PTS:	1

	17.	ANS:	G	PTS:	1

	18.	ANS:	E	PTS:	1

	19.	ANS:	H	PTS:	1

	20.	ANS:	B	PTS:	1