Telecor Administrative Communication Systems
Page 1
TEL-125, TEL-250
Power Amplifier Manual
1114 Westport Crescent; Mississauga, Ontario; Canada; L5T 1G1
April 22, 1997
Phone: (905) 564-0801 Fax: (905) 564-0806
E:\T2-37\T2-M37.WP
The Telecor TEL-125 and TEL-250 Power Amplifiers deliver 125 Watts and 250 Watts of power, respectively. These amplifiers will accept
either balanced or single ended input sources. A sensitivity “Input Level” switch is provided to select 1 V (0 dB) or 100 mV (-20 dB) input
levels. A 25 V input signal can also be used if the optional PA-AM Power Amplifier Attenuator module is installed (for details, see the
PA-AM Power Amplifier Module Manual
). Output terminals are provided for 4
Ω
, 8
Ω
, 25 V and 70 V speaker lines. The amplifiers have
current limiting circuitry on the output to protect the amplifiers from overloading. The amplifiers also have circuitry to protect them from
overheating. The TEL-125 and TEL-250 Power Amplifiers are both UL approved units (UL 813.)
The various amplifier parts are indicated in the figures to follow:
Figure 1: Front View of Power Amplifier
A
VU METER:
The 30 dB digital VU meter shows 0 dB when the amplifier is operating at its rated output. Exceeding the rated
output will cause the output to be clipped, which will be indicated by the illumination of the CLIP light.
B
HIGH TEMPERATURE Light:
When the internal temperature of the amplifier exceeds its normal operating limit, the “High
Temperature” light will illuminate and the output level will begin to be reduced. The amplifier will continue to operate at a reduced
output level until the temperature returns to an acceptable level. If the “High Temperature” light is illuminated, see the section on
Troubleshooting
.
C
CURRENT OVERLOAD Light:
When the current output of the amplifier exceeds its maximum power output, the “Current
Overload” light will illuminate and the output level will begin to be reduced. The amplifier will continue to operate with the current
limiting circuit reducing the output power. If the “Current Overload” light is illuminated, see the section on
Troubleshooting
.
D
GAIN Control:
The gain of the amplifier can be adjusted using this potentiometer. The potentiometer is concealed behind a snap-
on cover. The cover can be snapped off when the level needs to be adjusted but must be replaced to prevent unauthorized
tampering. The amplifier gain is set by both this control, and the sensitivity “Input Level” switch on the back of the amplifier.
E
POWER Switch:
Turns the amplifier on and off. The switch will illuminate when the amplifier is turned on.
