3
rd
Generation Dual Channel
Compact RDMS
TM
Telemetry Receiver-Combiner
108
Quasonix, Inc.
7 IF Module
The receiver’s integrated IF filter module, shown in Figure 159, includes eight (8) SAW filters, ranging in
bandwidth from 250 kHz to 40 MHz in approximately one octave steps. The standard eight filters are 250 kHz, 500
kHz, 1 MHz, 2 MHz, 4.5 MHz, 10 MHz, 20 MHz, and 40 MHz. These filters serve as anti-aliasing filters ahead of
the A/D converter in the demodulator itself. In addition, they can provide an added measure of adjacent channel
interference rejection. The measured responses of the eight filters are shown in Figure 160 and Figure 161 (note the
change of horizontal scale between the two figures).
Six additional filters are available allowing for a total of 14. The optional filters are 70 kHz, 1.4 MHz, 3 MHz, 6
MHz, 14 MHz, and 28 MHz. The measured responses of the optional filters are shown in Figure 162 and Figure
163. Contact Quasonix for information about the optional filters.
Based on the receiver’s high level of integration, the proper IF filter is automatically selected based on the current
mode and bit rate settings of the demodulator. Although manual filter selection is available, it is not recommended.
Figure 159
: 70 MHz IF Module in 2” x 3” Chassis
The IF module attaches directly to the demod modules.
