TM 11-6625-2781-14&P-2
Section IV
PERFORMANCE TESTS (cont'd)
4-25. Tuning Dial Accuracy
SPECIFICATION:
Display center frequency is within +1 MHz of indicated dial frequency on the 0-110 MHz tuning range; + 200 kHz on the
0-11 MHz range with FINE TUNE centered and temperature range of 20 to 30 degrees C.
DESCRIPTION:
Dial accuracy is verified by displaying test signals of known frequency accuracy. Test signals are the fundamental and
Figure 4-8. Tuning Dial Accuracy Test
EQUIPMENT:
Comb Generator ................................ ................................ ................................ ................................ ....... HP 8406A
BNC-to-BNC Cable Assembly ................................ ................................ ................................ ................. HP 10503A
Type N to BNC Adapter ................................ ................................ ................................ .......................... UG-201A/U
1. Connect the equipment as shown in Figure 4-8. Make the following control settings:
ANALYZER:
RANGE MHz ................................ ................................ ................................ ................................ ..................... 0-10
FREQUENCY ................................ ................................ ................................ ................................ ............... 10 MHz
BANDWIDTH ................................ ................................ ................................ ................................ ................. 30 kHz
SCAN WIDTH PER DIVISION ................................ ................................ ................................ ........................ 1 MHz
INPUT ATTENUATION................................ ................................ ................................ ................................ ..... O dB
LOG REF LEVEL ................................ ................................ ................................ ................................ ......... -40 dBm
SCAN TIME PER DIVISION ................................ ................................ ................................ ...... 10 MILLISECONDS
VIDEO FILTER ................................ ................................ ................................ ................................ .................. OFF
SCAN MODE ................................ ................................ ................................ ................................ ....................... INT
SCAN TRIGGER ................................ ................................ ................................ ................................ ............ AUTO
LOG-LINEAR ................................ ................................ ................................ ................................ ..................... LOG
8406A:
COMB FREQUENCY- MC ................................ ................................ ................................ ............................... 10 Mc
OUTPUT AMPLITUDE................................ ................................ ................................ ................................ .3 o'clock
2. Turn FREQUENCY to 10 MHz; a comb signal should be displayed +1 division of center graticule line.
-1
+1 DIV
4-11
