FM SOLID STATE AMPLIFIER KFS 1000

FM SOLID STATE AMPLIFIER
KFS 1000
° General. This FM amplifier is designed to operate on 87.5 - 108 MHz frequency range for FM radio
broadcasting appliances. It gives 1 kW of output power in continuous service.
° Lowest dimensions and weight in the market. A new coupling architecture permits a
dramatic reductions of, dimensions, weight and cooling, simplifing transport, installation and maintenance.
The amplifier height is only 132 mm (3U).
° COLD FET technology. This revolutionary technology is used in the KFS 1000 amplifier to optimize
the input matching of MOS-FET transistors in order to obtain
broadband amplification stages without any RF component. This means:
- high RF efficiency > 85%
- lower heating
- higher devices safety
- higher total reliability
- low AC power consumption
° Extraordinary RF efficiency: the COLD-FET technology allows to obtain from the amplifiers
the full power rating reducing of almost 20% the devices recommended operating DC voltage and current.
° Uninterrupted service. A proportional foldback protection circuit reduces the output power
without any on-air interruption, keeping the RF devices always within the safety conditions in case of:
- load mismatching
- environmental over-temperature
- cooling failure
- failure in one or more RF stage
- failure in power supply modules
° High modules redundancy: The KFS 1000 1 kW amplifier is composed of 4 x 300 W stages
coupled with high isolation combiners. This architecture assures the highest module redundancy.
° High gain 18 dB gain permits the full output power with low input driving.
° Broadband: no adjustments are required for the full power operation in the 87.5÷108 MHz band.
° The automatic power control circuit adjusts and stabilizes with precision (±1%) the maximum
output power in the whole band.
° The switch-mode power supply is largely oversized and guarantees a regular operation even
in the presence of wide main voltage fluctuations: the switching converters contribute to obtain a very
high AC to RF efficiency (67% typ.)
° Low overheating. The high cooling system efficiency limits at only + 10°C the heatsink
overheating respect to the environmental temperature. This permits the service even in overheated sites.
° Low consumption. The high overall efficiency means a reduction of AC power consumption and
operating costs.
° Reduced maintenance. Easy accessibility of all parts, no RF failure, no power supply failure,
external serviceable air filter reduce dramatically the maintenance costs.
° Metering. A complete metering system placed on the front panel permits the precise reading of: all
currents and voltages of each MOS-FET stage, forward power, reflected power.
° Remote control. It is available as option a remote control interface for the following parameters:
voltages and currents of each RF stage, forward power, reflected power, alarms status, on/off, stand-by.
° Meets or exceeds international standards for safety and electrical specifications.

KFS 1000
TECHNICAL CHARACTERISTICS
RF Specifications:
Operating frequency range
87.5 ÷ 108 MHz
Output power
0 - 1000 W adjustable
Input power
0 ÷ 20 W
Input connector
N
Output connector EIA 7/8” or DIN 7/16”
Input and output impedance
50 Ω
Harmonics and spurious emissions (ref. to carrier)
≤ -72 dBc
Synchronous AM (ref. 100% mod.)
< - 50 dB
Asynchronous AM (ref. 100% mod.)
≤-50 dB
RF probe
-50 dB, 50 Ω, SMA
Power stability < 2%
RF efficiency
78% typ.
Overall efficiency
64% typ.
Measures:
Forward power
Reflected power
DC supply voltage of each RF stage
DC supply current of each RF stage
Protections:
The internal logic circuitry provides proportional foldback protection, without on-air
interruptions, for:
- VSWR
- Air over-temperature
- Insufficient cooling
- Fault of RF stages (unbalancing)
Automatic power control:
The automatic power control circuitry regulates the output power with a precision of
2% over the whole band.
Remote control interface:
I-O connector
DB-25
Monitored & controlled functions:
- Stand-by
- Forward output power
- Reflected output power
- DC supply voltage of each RF stage
- DC supply current of each RF stage
- Alarms status

KFS 1000
TECHNICAL CHARACTERISTICS
AC Power requirements:
Operating voltage
Power drain at maximum power
110-220-240 ± 15% Vac 50/60 Hz, single.phase
1560 VA typ.
Other characteristics:
Cooling
forced air by internal fans
Service
continuous 24/24 h
Operating temperature -5 ÷ +45 °C/ 5 ÷ +104 °F
Relative humidity max. 95%
Max. Installation altitude 4000 m o.s.l.
Operating conditions:
Cooling
Temperature range
Humidity
Weight
Dimensions (W x D x H)
air forced, 12Vcc axial fan
-10° - +45° C
95% max
8 kg
483 x 430 x 90 mm
Mechanicals:
W x H x D 540 x 350 x 720 mm
Weight Kg 60
Options:
KFA/RC
Rack 19” - 6U
KFDC-48
full remote control interface
driver 19”-6U cabinet
48 VDC power supply
Features and specifications subject to change without notice.