Sensitivity And Burst Check, Channel - Racal Instruments 9916 Workshop Manual

TABLE 7
LF Decimal Point Check
Resolution
Display
Switch Setting
With LF Option Tolerance
Wit~out
LF Option
·100 Hz 00000.000 kHz
+ 1
count
88888.888 kHz
10 Hz 0000000.0 Hz
+ 1 count
8888888.8 Hz
1
Hz 000000 .00 Hz
+
5 counts 888888.88 Hz
O. 1
Hz
00000 .000 H z
+
50 counts 88888.888 Hz
. Sensitivity and Burst Check, Channel
IB I
5.19 Equipment required:
Item
Signal Generator
T piece
Terminating pad
Coaxial leads
Table 3 Item No.
4
6
7
8
5.20 Connect the T piece to the '8' Channel input socket of the UUT. Connect the
signal generator qnd the terminating pad to the T piece.
5.21 Set the controls of the UUT as follows:
(1) NORMA.ljBURST/CHECK switch to NOR/w\
L.
(2) OPERA TE/STAN )BY switch to OPERATE.
(3)
(4)
Channel 'B' selected.
RESOLUTION switch to 10Hz.
5.22 Set the signal generator output to 62 MHz at a level of 10 mV r.m.s. Set R85 to the
mid point of the range over which counting is- stable. Apply the frequencies shown in
Table 8 at a level of 8 mV r.m.s. (-29 dBm) '!Jith the RESOLUTION switch set as indicated.
Verify that a stable and accurate display is obtained at this level./
NOTE: If it has been necessary to change IC30 measure the input level reguired to give stable
counting with both C12 and R170 fitted. If the level is less than 4.5 mV r.m.s. remove
C12. If the
:\eveJ
is greater than 7.5 mV recnove R170.
5-8
?916Vol.2