Tektronix ECO422D, Инструкция по эксплуатации

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Performance Verification
5- 10
ECO422D SD/HD Changeover Unit Instruction Manual
3. PAL Black Burst Check for Channel 1 Primary
Switch between 2 and 4 dB down from nominal
Connect the equipment as shown in Figure 5--1.
Set the Channel Configuration switches to Disabled (signal not checked) for
all channels (set all the DIP switches on S2 through S11 to “open”).
Set the Channel Configuration switch to PAL Black Burst for Channel 1 (set
S1--1 to “open,” S1--2 “closed,” and S1--3 through S1--8 “open”).
Set the step attenuator to 0 dB of attenuation.
Set the TG700 BG7 to output a PAL black burst signal.
Press Reset.
CHECK -- that there are no errors shown for either the Primary or Backup
ECO422D sync sources.
Set the ECO422D to “Primary” Sync Source and Auto Switch “Switch on
Fault.”
Add attenuation, 0.5 dB at a time, to the Primary input signal until the signal
source switches to the 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 ECO422D does not continue to show the
Primary signal in error after the reset, continue adding attenuation until the
Primary signal switches to Backup again.
CHECK -- that the ECO switches between 2 and 4 dB down.
4. NTSC Black Burst Check for Channel 1 Backup
Switch between 2 and 4 dB down from nominal
Connect the equipment as shown in Figure 5--1, except swap the Primary and
Backup input signals at the ECO422D so that the step attenuator is on the
Backup channel.
Set the Channel Configuration switches to Disabled (signal not checked) for
all channels (set all the DIP switches on S1 through S11 to “open”).
Set the Channel Configuration switch to NTSC Black Burst for Channel 1
(set S1--1 to “closed” and SW1--2 through S1--8 “open”).