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APPLICATION
APPLICATION
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It is possible to install long speaker runs
with the
CPA-7B
,
M15W
and
PA-2A
.
To minimize the loss of audio power in long
speaker runs, a transformer is required at
both the amplifier end and at the speaker
end of a long wire run. A minimum of two
transformers are always required (Parts
Express 1-800-338-0531, part # 300-040).
The transformer at the amplifier is referred to as the step-up trans-
former; the transformer at the speaker is referred to as the step down
transformer.
Long Speaker Runs
with the CPA-7B,
M15W and PA-2A
August 29, 2005
Minimize the Loss of Audio in
Long Speaker Runs
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At the amplifier, connect the
8 OHM AUDIO OUTPUT
to the
8 OHM
and
COM
taps of the step-up transformer’s secondary coil as shown.
See chart below for pin selections.
Model CPA-7B
Model PA-2A
Model M15W
PAGING - LOUD RINGING
AMPLIFIER SYSTEM
VIKING
ELECTRONICS
HUDSON, WI 54016
VIKING
©
MODEL PA-2A
POWER 13.8
V
AC
1 2 3 4 5 6 7 8 9 10
NIGHT TRAN
SFER
SWITCH INP
UT
PA
G
ING
HORN
600 OHM AUDIO OUTP
UT
TRUNK / P
AGING
PO
RT
DR
Y CONT
ACT
CLOSURE IN
PUT
RINGING
VOLUME
MAX
MIN
1 - 3
4 - 6
RINGING LINES
1 2 3 4
TALK BATTERY
ALERT TONE
WARBLE / CHIME
PAGING
VOLUME
MAX
MIN
POWER
JP1
Step-Up
Transformer
Step-Down
Transformer
Long Wire Run
Parts Express part # 300-040
(or equivalent)
8 OHM
COM
A. Step Up Transformer
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1. Connecting the Audio Output
Select the step-up tranformer’s primary coil tap, which closest
matches the amplifier’s rated wattage output and connect
these taps to the beginning of the long wire run (see the chart
to the right).
Model
CPA-7B
M15W
PA-2A
Wattage
6
15
2
Tap
5
10
2.5
2. Selecting the Coil Tap
Model
CPA-7B
M15W
PA-2A
Pins
1 & 2
1 & 4
9 & 10