Fluke ScopeMeter 123, Service Manual, Page: 37 / 96

Performance Verification
3.5 Input A and Input B Tests
3
3-7
1. Short circuit the Input A and the Input B shielded banana sockets of the test tool. Use the
BB120 banana to BNC adapter, and a 50
Ω
(or lower) BNC termination.
2. Select the following test tool setup:
•
Turn Input B on (if not already on).
•
Press to select auto ranging (
AUTO
in top of display).
( toggles between
AUTO
and
MANUAL
ranging).
•
Fluke 123/124: press / to open the SCOPE INPUTS menu.
•
Fluke 123/124: press to open the SCOPE OPTIONS menu, and choose :
SCOPE MODE: NORMAL | WAVEFORM MODE: SMOOTH
•
Fluke 125: press to open MENU.
•
Fluke 125: press to open the TRIGGER menu, and choose :
UPDATE: FREE RUN
•
Fluke 125: press to open the SMOOTH menu, and choose :
WAVEFORM: SMOOTH
•
Press to leave the menus.
3. Using toggle the time base between 10 ms/div and 5 ms/div.
(the time base ranging is set to manual now, the input sensitivity is still automatic; no
indication
AUTO
or
MANUAL
is displayed).
After changing the time base wait some seconds until the trace has settled.
Observe the Input A trace, and check to see if it returns to the same position after
changing the time base. The allowed difference is
±
0.04 division (= 1 pixel).
Observe the Input B trace for the same conditions.
4. Using toggle the time base between 1
μ
s/div and 500 ns/div. After changing the
time base wait some seconds until the trace has settled.
Observe the Input A trace, and check to see if it is set to the same position after changing
the time base. The allowed difference is
±
0.04 division (= 1 pixel).
Observe the Input B trace for the same conditions.
5. Using set the time base to 10 ms/div.
6. Using toggle the sensitivity of Input A between 5 and 10 mV/div. After
changing the sensitivity wait some seconds until the trace has settled.
Observe the Input A trace, and check to see if it is set to the same position after changing
the sensitivity. The allowed difference is
±
0.04 division (= 1 pixel).
7. Using toggle the sensitivity of Input B between 5 and 10 mV/div. After
changing the sensitivity wait some seconds until the trace has settled.