Instruction Manual
Page 9 of 25
TRANSMITTER
No.
Parameter
Requirement
Comments
1 Modulation Type
DC/MA®
16QAM (2 level 8 phase) – Digital
Channel/Multicarrier Architecture
2 Output Power
4 Watts Pulsed Average
(Maximum)
3 Output Impedance
50
Ω
3 Harmonic Distortion
-57dBc
Two tone, third order products.
4 Microphone Impedance
3 k
Ω
5 Microphone Input
750
Ω
Parallel of microphone input and
microphone impedance is 600
Ω
6 Frequency Stability
Initial = 0.1 PPM
Temperature = 2.5 PPM
Aging = 1 PPM/yr.
Improved stability when synchronized to
the repeater. The repeater clock is stable
to ± 0.002 PPM.
7 Channel Frequency spread
18 MHz
8 Adjacent Channel Power Ratio
60 dBc
9 Occupied Bandwidth
20 kHz
An 800 MHz, 25 kHz DC/MA® channel is
divided into four sub-channels with
channel offsets of ±2400 Hz and ±7200
Hz. Each of the individual sub-channels
is about 4 kHz.
10 Transmitter Carrier Attack Time
< 0.5 msec
< 2 symbols with each symbol being 0.25
msec
RECEIVER
No.
Parameter
Requirement
Comments
1 Modulation Type
DC/MA®
16QAM (2 level 8 phase)
2 Sensitivity
0.45
µ
V (-114 dBm)
Based on 6% BER.
3 Input impedance
50
Ω
VSWR < 2.5:1
4 Intermediate Frequency
1
st
IF 86.85 MHz
2
nd
IF 450 kHz
5 Frequency stability
Initial = 0.1 PPM
Temperature = 2.5 PPM
Aging = 1 PPM/yr.
Improved stability when synchronized
to the repeater. The repeater clock is
stable to ± 0.002 PPM.
6 Channel frequency
spread
18 MHz
7 Spurious rejection
>70 dB
8 Adjacent Channel
Selectivity
>70 dB
Adjacent-channel FM-signal rejection
measured 25 kHz from the receiver
carrier.
9 Receiver IM Margin
>70 dB
Intermodulation of the receiver. Based
on cellular alternate channel definition
with F
1
at 50 kHz and F
2
at 100 kHz
from test channel.
10 Image rejection
>70 dB
11 Rated Audio output
0.5 W RMS into 8
Ω
(internal)
3.5 W RMS into 8
Ω
(external)
At < 5% @ 1kHz THD
