Crescend Technologies LLC P25XXFF1 Manual Do Utilizador
P25XXFF1
Power Amplifier User’s Manual
1. General Information
Power Amplifier (PA) is a AB/C-class unit. It is intended for amplification of single carrier phase (frequency)
modulated (manipulated) narrowband signals.
VHF range is divided by 4 working subranges:
-
136 – 144 MHz (subrange “DA”);
-
144 – 152 MHz (subrange “DB”);
-
152 – 162 MHz (subrange “EA”);
-
162 – 174 MHz (subrange “EB”).
Subrange code is reflected in the place “FF” of PA coding: P25-XXFF1-C6-001.
Code “XX” shows the input power range:
Code:
R1
R2
R5
1
2
5
10
20
Range, W: 0.1-0.2 0.2-0.5 0.5-1.0 1.0-2.0 2.0-5.0 5.0-10 10-20 20-50
In the normal operating mode the minimum output power is 250 W.
Input VSW R is not greater than 1.6:1.
PA meets all FCC requirements to harmonic and spurious levels.
Input VSW R is not greater than 1.6:1.
PA meets all FCC requirements to harmonic and spurious levels.
The nominal power supply voltage is 13.8 VDC.
DC current consumption does not exceed 50 A in the normal operation at 13.8V.
Working ambient temperature range lies from -30ºC to +60ºC.
DC current consumption does not exceed 50 A in the normal operation at 13.8V.
Working ambient temperature range lies from -30ºC to +60ºC.
Input and output power levels are set up in the factory. Customer has an opportunity to reduce the output power,
adjusting the special trimmer resistor in the unit, or picking up the value of outer resistor, connected to PA control pin.
PA has automatic power control loop that provides the stability of output power during the normal operation and all
necessary changes of power in the case of load mismatch or unit overheating.
PA is intended for rack mounting in the standard 19” cabinet. The front panel is 10” high. The
deepth of unit does not exceed 5”.
Four LEDs on the front panel indicate the status of unit operation.
The hole in the side wall gives an access to the trimmer resistor, which allows reducing the output power against the
The hole in the side wall gives an access to the trimmer resistor, which allows reducing the output power against the
set value.
There are two N connectors on the back of chassis.
There is power filtering DC connector at the back of chassis with four # 6-32 screws: 2 for “+” pole and 2 for “-“ pole.
There are 3 filter feedthroughs on the back of chassis that bring out the alarm signal, as well signals for the outside
There is power filtering DC connector at the back of chassis with four # 6-32 screws: 2 for “+” pole and 2 for “-“ pole.
There are 3 filter feedthroughs on the back of chassis that bring out the alarm signal, as well signals for the outside
power control.
Two fans on the back side of unit perform the forced air cooling.
2. Installation Guide
2.1. Unit installation shall provide proper air access to the unit; no obstacle for air is allowed
closer than 3” from fans.
2.2. Copper wires # 10 AWG shall be use in DC power line. Wires shall be crimped to ring terminals. Two parallel
wires shall be use for the positive voltage and two parallel wires shall be used for the ground side.
wires shall be use for the positive voltage and two parallel wires shall be used for the ground side.
Put terminal under PI-shape shunts on DC connector. Do not remove shunts!
3. Operation Guide
3.1. Power supply voltage shall be in the range 13.8 V + 0.8 V.
3.2. The input power within the working frequency range shall be within the listed above limits.
It is prohibited to apply any RF signal out of the working frequency range with a power, greater
than 10% of the minimum rated one.
than 10% of the minimum rated one.
3.3. Green LED “DC ON” is on, when DC voltage is applied to the unit.