TB 9-6625-2144-35
(b) Slightly increase or decrease toward 8.5 GHz (15.8 GHz) SIGNAL FREQ
control setting and readjust PHASE control to maintain peak indication of power meter.
(c) Continue process of (a) and (b) above until a sharp dip occurs when
FREQUENCY MC/10 dial indicates 850 (1580).
frequency and adjust POWER SET control for indication of SET POWER on SET
POWER meter.
(5) Set receiver system (A4) controls to establish a reference at 8.5 GHz (15.8 GHz).
(6) Set TRAN/TEST/RECV switch to RECV and adjust DBM control to -45.
(7) Measure attenuation with receiver system. The receiver system will display an
indication between 33.5 to 36.5 dB, add power meter Indication recorded in 10a(3) above
and total value will be between -43.5 to -46.5 dBm and record value (if making a new
correction chart, value recorded in this step will be expressed as a negative number
example: -46.5 dBm).
(8) Adjust receiver system controls to establish a new reference.
(9) Adjust DBM control to -50 and measure attenuation. receiver system display
will indicate a reading between 3.5 and 6.5 dB. Add power meter indication recorded in
10a(3) and receiver system indication recorded in 12a(7) above, total value will be between
48.5 to 51.5 dBm (if making a new correction chart, value recorded in this step will be
expressed as a negative number example -51.5) and record value.
(10) Repeat technique of (9) above for settings listed in table 6. Total recorded value
will be within limits specified.
Table 6. Attenuation Dial Accuracy
Test instrument
Total recorded value
DBM control indications
Min
Max
-55
8.5
11.5
-60
13.5
16.5
-65
18.5
21.5
-70
23.5
26.5
-75
28.5
31.5
-80
33.5
36.5
-85
38.5
41.5
1Total
recorded values are derived by adding power meter recorded indications in 10a(3), receiver system recorded indications
in 12a(7), and receiver system recorded indications in 12a(10) (Example -10 -35 -10 = -55 dB).
b. Adjustments. No adjustments can be made, however, a new correction chart will
be prepared and attached to TI if necessary.
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