TDS684C won't boot up - front panel lights stay on


Ryan Scott
 

Hi All:
I've acquired a Tek TDS 684C and it won't boot properly.  I'd like to fix it, but there is limited information available, and only to the module.  I followed the troubleshooting procedure from a 684a manual downloaded from Kurts w140 site.  Following the troubleshooting procedure, to the front panel/processor I have the clock signal and all the voltages are present at J2.  It states to replace the front panel module.  I pulled the module and could not find anything amiss.  I cleaned the menu buttons as they appeared dirty.  (thinking a leaky switch could hang the uP when it boots) When I powered it back up, it had more signs of life, but now it halts with a clock showing 9pm in the upper left hand side of the display.  
The display on the A11 board has the bottom horizontal segment lit.  - No other signs of life.
I cycled the power again (front panel) and it actually booted up.  
A quick power cycle (front panel) and it hung.  I don't think it's the front panel, when it booted the scope functioned as it should.  But now it's hung again.
Pulled the AC plug and cycled power again.  Boots.  Power on self test passed, signals displayed.  
It has the surface mount electrolytics on the front panel, but no leakage.  It also has the Dallas SRAM chips with the battery on chip.  

Power supply problem causing the uncertain boot?
Any other advice or ideas from the group?  
Thanks,Ryan ScottN7QJ

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