Checking For Continuity; Power Supply Check On The Terminal Pcb - Wyse WY-60 Maintenance Manual

Checking for Continuity
Sometimes you can fix the problem without opening the terminal.
The problem could be a damaged cable or power cord. Sometimes,
you may need to open the terminal to check the fuse or internal
connections. Check this list, then
r
with an ohmmeter, check the
continuity of the components listed below.
Outside the terminal, check the
o Power cord
o Communication cable (supplied with the computer)
Inside the terminal, check the
o Fuse
o AC power input receptacle (on the rear panel of the
terminal)
o Terminal PCB to the CRT/yoke wiring harness
Hold the probes in place for five seconds, or until the ohmmeter
settles, to ensure an accurate reading. If the part in question
is open, replace it.
Power
Supply Check on the Terminal PCB
You can quickly isolate problems if you check power supply
voltages on the terminal PCB.
Tools required:
o No.2 Phillips screwdriver
o Digital multimeter
o Nonconductive video alignment tool
To check the voltages, follow these steps:
1. Turn the terminal off.
2. Remove the terminal enclosure.
3.
Attach one lead from the DMM to the chassis as ground.
4. Turn the terminal on.
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