The power amplifier shall be a Bogen Model MT250D
Power Amplifier. It shall meet UL 1711 standard for
Fire Protective Signaling Systems and shall be designed
to operate from 120/240VAC (50/60Hz), and from a
24-volt battery backup system. It shall include a battery
saver circuit which shall automatically reduce idling
power requirements after at least 20 seconds of no sig-
nal.
The amplifier shall provide a rated output power of 250
watts with less than 2% total distortion at rated power,
50 to 15,000Hz. Frequency response shall be ±2dB
from 20 to 20,000. The noise level shall be 90dB below
rated output and regulation shall be better than 2dB
from no load to full load.
The front panel power switch shall be disabled such
that the amplifier remains “on” regardless of the posi-
tion of the switch. (An internal jumper shall be provid-
ed to enable the switch.) The unit shall be protected
against AC line surges, overloads, shorted output ter-
minals, and abnormal heat buildup.
The amplifier shall accept input from a high-impedance
unbalanced source or balanced low-impedance source
(requires accessory transformer).
Input impedance
(nominal, Hi-Z) shall be 50 kilohms; input sensitivity
shall be 1 volt for full rated output. Input impedance
(nominal, Lo-Z) shall be 600 ohms (requires the use of
an accessory transformer). Input sensitivity shall be
200mV with the input selector switch in the HIGH
LEVEL position, and 70mV with the switch in the TEL
LINE position. Provisions shall be included for bridging
input (requires accessory transformer).
Five output transformer taps shall be provided on the
rear panel: 12.5V, 25V, 8-ohm, 70.7V and 100V. A polar-
ized output receptacle shall be provided for the 100V
output. A low-cut filter switch and input level control
shall be provided.
The amplifier shall be housed in a sturdy 11-gauge
metal enclosure.
The front panel shall include
predrilled mounting holes for installation in standard
equipment racks. Front panel dimensions shall be 19”
wide x 5-1/4” high. Shipping weight shall be approxi-
mately 60 pounds.
Architects
and Engineers
Specifications
50 Spring Street, P.O. Box 575, Ramsey, New Jersey 07446
(201) 934-8500 FAX: (201) 934-9832
C O M M U N I C A T I O N S ,
I N C .
Rated Output Power:
250 watts rms
Total Harmonic Distortion:
Less than 2% at rated power, 50 to 15,000Hz
Frequency Response:
±2dB, 20 to 20,000Hz
Hum and Noise:
90dB below rated output
Regulation
:
Better than 2dB from no load to full load
Input Sensitivity:
1 volt for rated output, 200mV with Model TL600 transformer
70mV with Model TL600 transformer and HIGH LEVEL switch in
TEL LINE position
Input Impedance:
HI-Z 50,000-ohms nominal; LO-Z balanced 500/600 ohms with
Model TL600 transformer; 1:1 bridging with TL100 transformer
Controls and Indicators:
INPUT LEVEL control, illuminated POWER switch, LO-CUT
filter switch, HIGH LEVEL/TEL LINE sensitivity switch, OVER-
LOAD indicator
Constant Voltage Outputs:
12.5V, 25V, 70.7V, 100V
Speaker Impedance Output:
8 ohms
AC Power Consumption:
120VAC, 60Hz/240VAC, 50Hz, 650 watts, 30 watts standby
DC Current Consumption (24 - 28VDC):
18 amp; Standby with battery saver, 55mA; Standby without
battery saver, 1.6A
AC Line Fuse, Slo-Blo:
12 amp
DC Battery Fuse:
20 amp
Circuit Protection:
Thermal cutout, electronic overload circuit, power supply fuses
on AC & DC inputs
Auxiliary Receptacle (not switched*):
Three-wire grounded, 300 watts @ 120 volts
(except in 240V models)
Overall Dimensions (including removable feet):
19”W x 12-1/2”D x 5-1/2”H (48.3 x 31.7 x 13.9cm)
Front Panel Dimensions:
19”W x 5-1/4”H (48.3 x 13.3cm)
Finish:
Flat black
Shipping Weight:
60 lbs. (27.2 kg)
Accessory Equipment:
Model TL600, 600-ohm line matching transformer; Model TL100,
1:1 ratio transformer
*This receptacle will be grounded only if the power amplifier has been properly grounded.
Technical
Specifications
