Tektronix CSA7404B - Check Input Impedance

Performance Tests
4-90
CSA7404B, TDS7704B, TDS7404B, TDS7254B & TDS7154B Service Manual
H Move the signal to CH 1, set the Trigger SOURCE to CH 1, and
move the 50 Ω termination to the CH 4 input.
H Press PUSH TO SET 50%.
H SettheVerticalSCALEofCH1,CH2,CH3,andCH4to50 mV
H Set the test signal amplitude for about five divisions on screen. Now
fine adjust the generator output until the CH 1 Amplitude readout
indicates the amplitude is 250 mV. Readout may fluctuate around
250 mV.
H Remove the 2X attenuator.
H Repeat substeps a through g.
H Connect the 2X attenuator to CH 1.
H Move the coaxial cable to CH 1, set the Trigger SOURCE to CH 1,
and move the 50 Ω termination to the CH 4 input.
H SettheVerticalSCALEofCH1,CH2,CH3,andCH4to10 mV
H Set the test signal amplitude for about five divisions on screen. Now
fine adjust the generator output until the CH 1 Amplitude readout
indicates the amplitude is 50 mV. Readout may fluctuate around
50 mV.
H Remove the 2X attenuator.
H Repeat substeps a through g.
6. Disconnect the hookup: Disconnect the cable, terminations, and adapters
from the generator output and the input connector of the channel.
Equipment
required
One Digital Multimeter (Item 27)
One Dual-Banana Connector, (Item 5)
One precision 50 Ω coaxial cable (Item 4)
One SMA male-to-female BNC adapter (Item 19)
Prerequisites See page 4--17
Check Input Impedance