Changing the power board did not help in this situation, but changing the signal board did fix it!
Not sure what could go wrong on that board, but I understand that there are electronics companies that can fix the components on that board too if I had needed to do that.
This is a 2009 HDTV, not subject to the famous 2008 recall for bad capacitors on the 'A' models.
The problem started last week when the power button on the front of the TV would not turn the TV on or off, but the remote control still could. Now suddenly the remote control can't do it either. Ditto for the Blu-ray player's HDMI power on feature also. The behavior is still different, however. When the power button on the TV is used, the red standby indicator does not go off or begin to flash. However, when the remote's power button is used, the standby indicator goes off and does not come back on. The power button on the TV is not dead, however. If I press the power button, then the remote's button also does nothing.
It seems very much like the TV is getting hung in software during the power on process. The power-on musical chime never sounds, and there is no clicking noise either. I opened the back and did not see any exploding capacitors, and both ceramic fuses were not blown.
The big questions is could this still be a power board issue? I really don't want change the signal board; that's the guts of the TV! The different behavior between the power button on the TV and on the remote is what bothers me the most ...

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