User's Manual

044-05156 Rev C 25
Note 1: Service loop grounded allows the MCPA to be enabled or disabled by the front panel switch when not
mounted in the shelf.
4.5.5 Pilot Tone Control
The multi-amplifier subracks can be used to control the pilot tone frequency of the installed amplifiers. Pilot tone
frequency selection is based on the intended operational band of the amplifiers per the following table.
Pilot Frequency Setting Based on PCS Frequency Block of Operation
Transmit Frequency Band (MHz)
Block Designator
Base Station Bandwidth Pilot (MHz)
A 1930-1945 15 1945.5 (A)
D 1945-1950 5 1950.5 (D)
B 1950-1965 15 1965.5 (B)
E 1965-1970 5 1964.5 (E)
5 1965-1970 5 1970.5 (5)
F 1970-1975 5 1969.5 (F)
C 1975-1990 15 1974.5 (C)
Block Pairs
A-D 1930-1950 20 1950.5 (D)
D-B 1945-1965 20 1965.5 (B)
B-E 1950-1970 20 1970.5 (5)
E-F 1965-1975 10 1964.5 (E)
F-C 1970-1990 20 1969.5 (F)
E-C Excluding F 1965-1990 Excluding: 1970-1975 25 1974.5 (C)
Notes:
1. If the Block Designator has not been previously selected through serial communication on connector
J10M, pilot defaults to 1960.5 MHz on the G3S-1900-80 amplifier; 1964.5 on the G3S-1900-125
amplifier
2. If the Block Designator is selected through serial interface on connector J10M, pilot frequency is moved
to the appropriate spot and is stored permanently into the microprocessor until another band is
changed.
If the pilot tone is not moved and signals are transmitted in B-band, some traffic channels may transmit directly on
the pilot tone. The pilot tone requires a guard band of 60 KHz for TDMA, 270 KHz for CDMA (IS-95), and 400 KHz
for GSM. Transmitting on the pilot tone will cause the amplifier to go into Loop Fail. This will not damage the MCPA.
However, CDMA customers will experience a Loop Fail in every sector where the amplifiers are installed. TDMA
and GSM customers will experience intermittent Loop Fails in the sectors that use these frequencies.
On the other hand, if the pilot tone is not moved and signals are transmitted in A-band (1930-1945) or C-band
(1975-1990), the instantaneous bandwidth of the amplifier will be exceeded. This will cause equipment operated in
the outer bands of the PCS band to experience higher intermodulation distortion, which may in turn cause them to
exceed FCC emission limits. The lower end of the PCS band presents the farthest frequency span from the pilot
tone, which begins at 1930 MHz; 30.5 MHz away from the pilot tone of the G3S-1900-80 amplifier; 34.5 MHz away
from the pilot tone of the G3S-1900-125 amplifier.
Setting the pilot tone frequency of the amplifiers requires a laptop interface program. The laptop can be connected
to the multi-amplifier subrack’s RS-232 port. The multi-amplifier subrack provides the interface to the amplifiers to
set their pilot frequency and stores this setting in memory. If an amplifier fails, the multi-amplifier subrack programs
the pilot frequency of the replacement amplifier to that of the other installed amplifiers.
Refer to the Site Preparation and Installation Manual or Field Replaceable Units manual for the pilot tone
configuration procedure. Contact Powerwave to obtain a copy of the program and related instructions.