paging lesson 2

Question 1

70v output amplifiers are used _________

Answer 1

primarily for paging systems

Question 2

Constant voltage systems use how many wires and what are they for?

Answer 2

2 wire

audio power is supplied from the centralized amplifier

Question 3

the raw 24v DC power needed by a self amplified system can be carried in a ___________since it carries no interfering signals

Answer 3

telecom cable

Question 4

a self amplified system audio signal is the same as you would find on any _________

Answer 4

analog telephone

Question 5

how many wires does a self amplified system require and what are they for?

Answer 5

2 pairs of wires

one pair for audio and one pair for 24v DC power

Question 6

what are speaker taps for?

Answer 6

select peak power that the speaker will consume

Question 7

lower current =___________

Answer 7

less voltage drop

Question 8

a slc provides a simple and cost effective way to remotely control volume of a network of up to______ speakers

Answer 8

150

Question 9

reducing the current flow in a wire by a factor of ____ will reduce the power loss by a factor of ______

Answer 9

2

4

Question 10

direct output amplifiers are used with _____________

Answer 10

low impedance speakers

Question 11

microphone cable is always _____

Answer 11

shielded

Question 12

low signal levels prevent _______

Answer 12

crosstalk

Question 13

25, 16, and 8 ohm amplifiers are used __________

Answer 13

for strict building code requirements

Question 14

do not run 70v system cables with__________

Answer 14

analog phone lines

Question 15

limit AUX input cables to ________ feet. longer cables equal ___________

Answer 15

6 feet

more noise

Question 16

step down audio transformers are located_______

Answer 16

on the speaker and tapped at various levels

Question 17

bufex

Answer 17

local volume controls for a group of speakers

Question 18

when sending power signals over long distances it is important to minimize the amount of _________ in the wire

Answer 18

current

Question 19

Aux inputs have a ___________ signal

Answer 19

unbalanced

Question 20

what are 2 ways to acomplish paging

Answer 20

• 25v or 70v centralized amplifiers with passive speaker

- self amplified speakers operating with a 24v power supply

Question 21

reducing the current in a wire will reduce _________

Answer 21

power loss

Question 22

SLC

Answer 22

signal level control

Question 23

what is the formula used to determine the amount of current flow in the speaker wires?

Answer 23

I = √(P/R)

Question 24

a slc provides a simple and cost effective way to remotely control ________ of a network of up to 150 speakers

Answer 24

volume

Question 25

how many cables does a microphone have ___________. what are they?

Answer 25

3

2 for a balanced signal and 1 for ground/shield

Question 26

why use a 70v outputs

Answer 26

low current allows long runs

Question 27

MIC inputs have a _______ signal

Answer 27

balanced

Question 28

what feature allows emergency announcements to be heard at higher levels than the volume setting on the volume control?

Answer 28

bypass