Tektronix WFM601, Руководство по обслуживанию

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Performance Verification
WFM 601 - Service Manual
4–15
f. CHECK – that there are dots in all targets.
15. Check Bowtie Interchannel Matching
REQUIREMENT – Null must occur within
$
2.0 ns of center marker.
a. Select the high frequency (2.5 MHz) bowtie signal from the serial digital
component generator.
b. Turn on WFM 601 BOWTIE VIDEO DISPLAY.
c. Turn on SWEEP MAG.
d. Position display to place the null and center marker of the Bowtie
display onto the graticule area. See Figure 4–3.
20 ns
4 ns
NULL
Figure 4–3: HF Bowtie Magnified to Measure Null Offset
e. CHECK – that the Bowtie null point occurs within 0.5 divisions (2.0
ns) of the Bowtie center marker. See Figure 4–3.
16. Check Analog Audio Display Mode
REQUIREMENT – Audio Mode Full Scale Accuracy:
"
0.5 dB.
a. Select AUDIO DISPLAY.
b. Enter the GAIN menu and select 0 dBu.
c. Center the display dot using the VERT and HORIZ POS controls.