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.5.5.7
•. :,!" •.
~
.•
:·:;···1·
\
\
3. Set the signal generator for an output of 1.5 MHz, CW at a level 0[-100 dBm.
4. Note the IF output level indicated on the RF voltmeter.
5. Remove the 50 ohm load from the IF output and observe that the indicated output
voltage increases by 6 dB
±
I dB.
6. Connect the frequency counter to IF output jack J2 and measure the IF frequency.
This should be 455.000 kHz.
Fixed and Variable BFO Operation
1. Set the receiver controls as follows:
a. Power
ON
b. Gain Mode
N/A
c. Detection Mode
CW
d.
BW
N/A
e. BFO
ON (word BFO displayed
in
Mode LCD) .
2. Disconnect the A4 module by removing WI OPI.
3. Connect the frequency counter to A4J6 to monitor the BFO frequency.
.
."
.
-
4.
Using the receiver front panel controls,
s~lecteach
BFO indication listed in BFO
Indicator column of Table 5-5 and verify the frequencies listed
in
BFO Frequency
Column are obtained.
.
.
-
-
:
.:
-~
.
.
-
-
.
-
5. Select USB and LSB modes andobseryetheBFO frequency·iS 455.000 kHz: .
. (SSB/ISB receivers flttedwith 08409a.n.d08410 option flltersonly.) ..
" .
6. Disconnect frequency counter and reconnect W10PI to A4 module.
TABLE 5-5. BFO Test Values
BFO Indicator
BFO Frequency
0.00 kHz
455.000 kHz
..
+
1.11
453.890
2.22
452.780
3.33
451.670
4.44
450.560
5.55
449.450
6.66
448.340
7.88
447.120
7.99
447.010
-1.11
456.110
_I ..,,,
457.220
-3.33
458.330
-4.44
459.440
-5.55
460.550
-6.66
461.660
-7.77
462.770
-7.88
462.880
-7.99
462.990
5-14
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