Broadcast Electronics FX-50, Instruction Manual

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©2011 Broadcast Electronics
1.5.2 STATUS DISPLAYS.
The FX-50/E exciters are designed with front-panel LEDs to indicate the status of three main exciter operating
potentials, three preset limits, and operating frequency stabilization. Additional LEDs are incorporated on the
AFC/PLL circuit board assembly to indicate the status of operating potentials and monitor reference oscillator
and modulated oscillator circuit conditions.
1.5.3 AUTOMATIC FREQUENCY CONTROL.
A temperature compensated reference oscillator and a dual-speed phase-locked-loop controlling the carrier
frequency locks the frequency of the modulated oscillator to the precision reference frequency oscillator
allowing prompt on-frequency operation of the exciter from a cold start. The FX-50/E will achieve frequency
lock from a cold start in less than five seconds.
1.5.4 CONTROL CIRCUIT.
The control circuitry provides automatic control of RF output to maintain a preset power output. In addition,
the control circuitry eliminates adjustments after the initial setup, protects the RF output circuitry from excessive
temperatures, high VSWR conditions, over-voltage conditions, and short circuit conditions.
RF AMPLIFIER.
The RF amplifier is a broadbanded 3 to 50 watt amplifier covering the entire commercial FM broadcast band.
Tuning of the amplifier is not required. An optional low-pass filter can be installed in the exciter to convert the
exciter to a low power transmitter for connection to an antenna.
1.6 EQUIPMENT SPECIFICATIONS.
Refer to Table 1-1 for electrical specifications and Table 1-2 for physical and environmental specifications of the
FX-50/E FM Exciters.
Table 1-1. FX-50/E Exciter Specifications
PARAMETER SPECIFICATIONS
AC INPUT POWER REQUIREMENTS
FX-50
FX-50E
97 to 133V AC or 194 to 266V AC, 50/60 Hz, 230W Maximum
240V AC Nominal, 50/60 Hz, 230W Maximum.
RF OUTPUT IMPEDANCE 50 Ohms.
POWER OUTPUT 3 Watts to 50 Watts, Continuously Variable (BNC Connector)
Open and Short Circuit Protected.
R.F. HARMONIC AND SPURIOUS
SUPPRESSION (CONDUCTED) Meets or exceeds all FCC, DOC, and CCIR standards.
FREQUENCY RANGE 87 MHz to 109 MHz Digitally Programmable in 10 kHz
increments.
FREQUENCY STABILITY + 300 Hz, +32˚F to +122˚F (0˚C to +50˚C).
MODULATION TYPE Direct FM at the Carrier Frequency.
MODULATION CAPABILITY +350 kHz.