Tektronix ECO 422, Instruction Manual

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Performance Verification
ECO 422
5–15
Set the Channel Configuration switches to Disabled (signal not checked) for
all channels (set all the DIP switches on S1 through S11 to “closed”).
Set the Channel Configuration switch to NTSC Serial Digital Video
Composite for Channel 1 (set S1–3 to “closed,” S1–1 and S1–2 “open,” and
S1–4 through S1–8 “open”).
Set the step attenuator to 0 dB of attenuation.
Set the TSG 170D to output any serial digital signal.
Press Reset.
CHECK – that there are no errors shown for either the Primary or Backup
ECO 422 sync sources.
Set the ECO 422 to “Primary” Sync Source and Auto Switch to “Switch on
Fault.”
Add attenuation, 0.5 dB at a time, to the Primary input signal until the signal
source switches to Backup.
Press the Reset button on the front panel and try to return the signal source
to Primary.
CHECK – that the Primary signal still shows an error and automatically
switches back to Backup. If the ECO 422 does not continue to show the
Primary signal in error after the reset, continue adding attenuation until the
Primary signal switches to Backup again.
Note the attenuation of the step attenuator.
CHECK – that the ECO switches between 2 and 5 dB down.
11. NTSC Serial Digital Composite Check for Channel 1 Backup
Switch between 2 and 5 dB down from nominal
Connect the equipment as shown in Figure 5–3, except swap the Primary and
Backup signals, so that the step attenuator is on the Backup input.
Set the Channel Configuration switches to Disabled (signal not checked) for
all channels (set all the DIP switches on S1 through S11 to “closed”).
Set the Channel Configuration switch to Serial Digital Video Composite for
Channel 1 (set S1–3 to “closed,” S1–1 and S1–2 “open,” and S1–4 through
S1–8 “open”).
Set the step attenuator to 0 dB of attenuation.
Set the TSG 170D to output any serial digital signal. (Do not use the SDI
Check Field signal.)