RFL Electronics 9780 - Table 12-2. Receive Frequency Select Switches

RFL 9780 RFL Electronics Inc.
April 8, 2003 12-6 (973) 334-3100
12.4.1 RECEIVE FREQUENCY SELECT
The first mixer stage of the IF/BF Module must be configured for the center frequency of the receive
signal. Switches SW1 and SW2 are used to set the receive frequency. The resolution of the switch
setting is 250 Hz and is selected by switch SW1-1. The next switch (SW1-2) has twice the value of
SW1-1, and so-on. The value of each receive frequency setting switch is given in Table 12-2.
The switches are cumulative (the sum of all of the individual switch values gives the total frequency
setting). The frequency selected by SW1 and SW2 must be set for 2 kHz less than the center frequency
of the receive signal, rounded down to the nearest 250 Hz.
For example, a receive frequency of 68.5 kHz would be set as follows:
68.5 kHz – 2 kHz = 66.5 kHz
SW2-5 OFF 64.0 kHz
SW1-4 OFF 2.0 kHz
SW1-2 OFF 0.5 kHz
TOTAL 66.5 kHz
Table 12-2. Receive Frequency Select Switches
Switch Value (kHz)
Switch ON OFF
SW1-1 0 0.25
SW1-2 0 0.5
SW1-3 0 1.0
SW1-4 0 2
SW2-1 0 4
SW2-2 0 8
SW2-3 0 16
SW2-4 0 32
SW2-5 0 64
SW2-6 0 128
SW2-7 0 256
SW2-8 0 512