TB 9-6625-2185-24
Table 7. Upscale Accuracy Measurements
Synthesizer/level generator
Display
Record out-of-tolerance
output
indications
indications and
(dBm)
corresponding range
Min
Max
-24
-23.92
-24.08
Range 1
-14
-13.92
-14.08
Range 2
-4
-3.95
-4.05
Range 3
+6
+5.92
+6.08
Range 4
(28) Calculate upscale corrections for out-of-tolerance ranges using formula as
shown in example below:
Example:
New gain factor = old gain factor + (TI error X 1200)
NOTE
For every 0.01 dB of error, a correction of 12 counts must be
added or subtracted to gain factor. Gain factors were recorded
in (12) above and table 4.
Example:
Display indicates -24.16 dBm
Actual power level is -24.00 dBm
TI error is .16 dB low (add to gain factor)
Gain factor from table is 5032
New gain factor = 5032 + (0.16 X 1200)
New gain factor = 5224
(29) Set control board bit switch to CALIBRATE MODE 2 (AC CAL) (fig. 3).
(30) Press pushbuttons N, RANGE HOLD, XXXX, REF LVL dB.
NOTE
N is out-of-tolerance range, XXXX is new gain factor from (28)
above.
(31) Set control board bit switch to OPERATE MODE (fig. 3).
Repeat
paragraph 9 a above.
(32) Connect equipment as shown in figure 2, CONNECTION A.
synthesizer/level generator output to within RF power amplifier input operating range.
Slowly increase RF power amplifier gain control for a power meter indication of 0 dBm.
(34) Use precision power measurement technique, calculate and record calculated
power as P2.
14