Tektronix 410, Service Manual

Page: 96 / 275

Performance Tests
TDS 410, TDS 420, & TDS 460 Performance Verification
1Ć27
Checking the bandwidth of each channel at all vertical scale settings
is time consuming and unnecessary. You may skip checking the
remaining vertical scale settings in Table 4-3 (TDS 410 and TDS 420)
or Table 4-4 (TDS 460) (that is, skip the following substep, h) if this
digitizing oscilloscope has performed as follows:
H
Passed the 100 mV vertical scale setting just checked in this
procedure.
H
Passed the Verify Internal Adjustment, Self Compensation, and
Diagnostics procedure found under Self Tests, on page 4-4.
NOTE
Passing the signal path compensation confirms the signal path for
all vertical scale settings for all channels. Passing the internal
diagnostics ensures that the factory-set adjustment constants that
control the bandwidth for each vertical scale setting have not
changed.
h. Check remaining vertical scale settings against limits (optional):
H
If desired, finish checking the remaining vertical scale settings for
the channel under test by repeating substeps d through g for
each of the remaining scale settings listed in Table 4-3 (TDS 410
and TDS 420) or Table 4-4 (TDS 460) for the channel under test.
H
When doing substep e, skip the subparts that turn on the CHx
Pk-Pk measurement until you check a new channel.
H
Install/remove 10X attenuators between the generator leveling
head and the channel input as is needed to obtain the six division
reference signals listed in the table.
i. Test all channels: Repeat substeps a through g for all channels.
3. Disconnect the hookup: Disconnect the test hook up from the input con-
nector of the channel last tested.
Check Delay Match Between Channels
Equipment Required: One medium-frequency leveled sine-wave generator
(Item 11), one precision coaxial cable (Item 5), one 50
W
terminator (Item 3),
and a dual-input coupler (Item 9).
Prerequisites: See page 4-13.
Procedure:
DO NOT use the vertical position knob to reposition any channel
while doing this check. To do so invalidates the test.
1. Install the test hookup and preset the instrument controls: