User's Manual

TX RX Systems Inc. Manual 7-9469-1.7 02/08/10 Page 1
OVERVIEW
Signal boosters extend radio coverage into areas
where abrupt propagation losses prevent reliable
communication. The system receives an RF signal,
raises its power level, and couples it to an antenna
so that it can be re-radiated. The TXRX model 611-
70A channelized signal booster is designed to
operate in the 450 to 512 MHz range. The system
is based on a module design with each module
capable of handling one uplink and one downlink
channel simultaneously. The size of the system
can be tailored to the customers needs by increas-
ing or decreasing the number of modules used.
Each module is bi-directional with one downlink
and one uplink signal branch. Each of the two
branches in a module are independently tunable to
their required pass frequency via software inter-
face. Specifications for the 611-70A family of chan-
nelized signal boosters are listed in Table1.
Down / Up Conversion
A channelized signal booster has much in common
with a superheterodyne (superhet) receiver. The
incoming signal is converted to a lower frequency
so that single channel selectivity can be obtained.
It is then filtered. Unlike the superhet receiver how-
ever, the signal is not demodulated. Instead, it is
up-converted back to its original frequency where it
is further amplified to reach a useful power level.
Intermediate
Frequency
Signal
Processing
1st Mixer 2nd Mixer
RF OutRF In
Local
Oscillator
Figure 1: The down converter / up converter process.
Frequency Range 450 - 512 MHz
Number of Carriers
per Channel
1 Uplink
1 Downlink
Nominal Passband Gain
Downlink
Uplink High Power
Uplink Low Power
120 dB
120 dB
100 dB
Channel Bandwidth
Standard 25 KHz;
can be programmed to
meet group delay require-
ments
(User Selectable)
Rated Power
Downlink
Uplink High Power
Uplink Low Power
+ 39 dBm ERP
+ 39 dBm ERP
+18 dBm ERP
Maximum Input Level -40 dBm
RF In/Out Impedance 50 Ohms
Alarms
Form-C Contacts
Module LED’s
Power
90 - 250 VAC, 50/60 Hz
or
28 VDC (+/- 5%)
Operating Temperature
Range
-30°C to +60°C
Table 1: Specifications