PERFORMANCE TEST
4 - 13
4.3.10
Vertical deflection; high-frequency response
This test verifies the upper transition point of the vertical bandwidth.
Test equipment:
Fluke 5500A mode: levsine (Alternative: constant amplitude sine wave generator
SG 503).
Test set-up:
Settings/procedure:
1
-
Apply a 50 kHz sine wave signal of 600 mV (pp into 50
Ω
) to input CH1,
and press the AUTOSET key.
2
-
Use an external 50
Ω
termination. Use the internal termination of the
oscilloscope, when available (if active, the text ’LZ’ is visible in the lower
part of the viewing area). Internal 50
Ω
termination is attainable via the
VERT MENU key (PM3390B/94B).
3
-
Set CH1 to 0.1V/div.
4
-
Adjust the input signal to an amplitude of exactly 6 divisions.
5
-
Slowly increase the frequency to 200 MHz (PM3390B, PM3394B),
100 MHz (PM3384B, PM3380B) or 60 MHz (PM3370B) and verify that the
displayed amplitude does not drop below 4.2 divisions.
6
-
Switch the frequency of the sine wave signal back to 50 kHz.
-
Press the ACQUIRE menu key.
8
-
Select BW LIMIT ’on’ via the VERT MENU key.
9
-
Slowly increase the frequency to 20 MHz and verify that the vertical
deflection has decreased to 4.2 div approximately at 20 MHz.
10 -
Switch the bandwidth limiter to ’off’.