Fluke 6060B Instruction Manual page 154

MAINTENANCE
TROUBlESHOOTING AND REPAIR
The four groups (denoted by the A's, B's, C's and D's) in the self-test report corr
different test categories. These tests are described below, including a tabulation of the
Generator instrument state and the test codes that result if any test fails to achieve the
expected result. Unders
results and can assist in understanding how they relate to other symptoms. A successful
self test is reported with all zeros.
During the self test, the step attenuator is programmed to maximum attenuation and the
internal frequency reference is seiected. The analog circuit tests m
(UNLVL) and unlocked (UNLOK) status detectors, whereas the digital circuit tests make
use of write/ read techniques.
4D-18.
AAA is the result of the AM and FM tests
During the four AM tests, a normal AM depth, which should produce a leveled
condition, and an abnormally high A M depth, which should provide an unleveled
condition, is set for each modulation fre
deviatio n is set, which should produce a locked condition, and then an abnormally high
performed ifthe Option -65 1 Low-Rate FM is installed. Table4D-3 shows theAAA Field
deviation is set, which should produce an unlocked condition. The two FM tests are not
AM and FM tests.
4D- 1 9.
BBB is the result of the synthesizer tests. I n the first three test steps, the Synthesizer
assembly's main
This should cause a momentary unlocked condition that should
settles to the new frequency.
AAA
( COOEl
001
002
004
01 0
020
040
In the next three steps, the synthesizer is checked by programming 225 MHz, which is
outside the normal operating frequency range, and should result in an unlocked
condition. Then 385 MHz is programmed, which should result in a locked condition.
Next 550 MHz is programmed, which is again outside the normal range, and should
result in unlocked condition.
Finally, all frequency reference circuitry is turned off, which should
condition, and then turned on, which should produce a locked condition. Table 4D-4
shows the BBB Field test results.
4D-20.
CCC is the result of the digital tests. The I EEE-488 option (if installed) is verified b y
writing data to the IEEE-488 chip, A3A3Ul,
expected response.
checksum.
40-6
g
andin how these tests are done can pr
t
FI ELD
AAA
BBB FIELD
P L L
operation is verified by programming a large change in frequency.
Table 40-3 AAA Field AM and FM Tests
MOD
FREQ lEVEl AM
m
<MHZ) (OBM)
3 0
1 050 1 0 . 7
1 050 1 27
1 4
3 0
1 05 0 1 0 . 7
1 27
1 050
1 4
-1 0
2 80 n/a
280 -1 0 n/a
CCC FIELD
Each
memory location of the N on-Volatile RAM is checked with
o
vide more meaning to the
a
.
During these tests, level correction is applied.
q
uency. During the two FM tests, a no
clear
FM
FREQ KV
OAC
<HZ) DAC
n/a
400 n/a
n/a n/a
400
n/a n/a
1 000
n/a n/a
1 000
Normal
1 023
400
1 023
400
1 023
then
by reading it back and checking for the
e
spond to
ke use of the unleveled
mal FM
r
as the frequency
FM
EXPECTED
RANGE
RESUlT
Leveled
n/a
unlevelea
n/a
n/a
Leveled
a
n/
Unleveled
Locked
4
U n l ock�d
4
p c
rodu e an unlocked
a
t