Motorola BLE*/* - Manual (Page 18)

Overview 2-7
BLE*/* Installation and Operation Manual
Forward Path
The operational gain of the E-GaAs BLE*/* amplifiers is 28 dB or 32 dB (depending on model)
with 16 dB of return loss. The operating gain includes provisions for the insertion loss of the
input cable equalizer and required reserve gain to operate the Bode equalizer in the middle of
its range. The low-noise figure, pre-amplifier stage, is a conventional 870 MHz hybrid followed
by a power-doubled output stage. Between the two stages is a JXP-*B pad socket, the Bode
board, and the flatness and equalizer board. Because these losses are located interstage, the
noise figure is only significantly impacted by the insertion loss of the forward cable equalizer or
broadband cable simulator, and the input pad if its value is increased from zero.
Figure 2-7 illustrates the interconnection among these components:
Figure 2-7
BLE*/* block diagram
Input
port **
** ** ** **
SFE
or
SCS
JXP-B JXP-B RCB PP PD
-20 dB
TP
**
Manual
**
LDR
H
L Auto
ADU/
TDU
-1.0 dB
-1.0 dB
-1.0 dB
24 dB -6.5 dB -1.0 dB
-1.0 dB
(~0.0 dB
with jumper)
RF/
AC
AC
RF
Std Gain E-GaAs: 18 dB
High Gain E-GaAs: 23 dB
TP
Return
injection point
-20 dB
Output
port
**
H
L
**
SRE
-16 dB
LPF
**
Therm
TP
-20 dB
** **
**
ICS JXP
** JXP-B
TP
-20 dB
24 Vdc
DC test point
AC test
point
Power
supply
Fuse
Power
Block
Jumper
** Plug-in module
FTEC
**
-1.0 dB
-1.0 dB
-0.5 dB
+25.0 dB L
+30.0 dB H -0.3 dB
-0.4
dB
-0.4 dB -0.4 dB
RF/
AC
AC
RF
-1.7 dB
FWD
-1.7 dB
FWD
-1.0 dB
RTN
-1.0 dB
RTN
OnBrd
Atten
**
Status
monitor
BODE
Return Path
The circuit board of the BLE*/* accommodates the optional return path. The return path kit,
model RA-Kit/H or RA-Kit/L, includes the return amplifier hybrid (illustrated in Figure 2-8) and
jumpers. This equips the BLE*/* to pass signals in the return or upstream direction. The
standard circuit board contains all components including the diplex filters with extended return
bandwidth for the amplifier input and output. All items are plug-in and easily installed.
Optional SRE-*-* return equalizers compensate for cable attenuation and are available in 1 dB
increments for S-split, and 2 dB increments for all other splits, from 0 dB through 12 dB.