THM500 Series Performance Verification
Bench Test Instruments and Handheld Oscilloscopes Basic Service
23
The following check assesses the DC offset.
1.
Use the THM500 series instrument menus to select
RESET ALL
. This sets
the vertical position to zero.
2.
Return the THM500 series instrument to
SCOPE
mode.
3.
Use the THM500 series instrument
UTILITY
menu to select
CH 1
OFFSET
. This automatically adjusts the channel offset.
4.
Use a patch cord to short the THM500 series instrument COM and CH 1
inputs as shown in Figure 11.
THM5xx
CH 1
COM
Patch cord
Figure 11: DC offset test setup
5.
Press the THM500 series instrument
POSITION/SCALE
button until the
readout shows
SCALE
in the lower-right corner; then use the
Y
and
B
buttons to set the CH 1 vertical scale to
5 mV/div
.
6.
Verify that the offset is less than four pixels from the center graticule line.
7.
Use the
Y
and
B
buttons to set the vertical scale to the next range.
8.
Repeat steps 6 through 7 above until you have checked all ranges (10 mV/
div through 500 V/div).
9.
If your THM500 series instrument is equipped with two channels, repeat
steps 3 through 8 above for CH 2.
10.
Disconnect the test setup.
11.
Use the menus to return the THM500 series instrument to the factory default
settings; select
RESET ALL
.
NOTE
. Return THM575 products to the initial language selection (if you changed
the language selection). You will find these selections in the Utility menu.
DC Offset
