"John Miles" wrote in message
...

I'm not sure what would cause random or non-standard power-up settings
besides a flaky keyboard controller that doesn't respond to the CPU's
first few accesses after power up. The 496 doesn't have the capability
to store its settings in NVRAM like the 494 and later models, so it
shouldn't be a case of corrupted memory. The EPROMs are checksummed, so
if you don't receive any power-up error messages, they are OK.

I suppose one worthwhile test would be to make *sure* that the UNCAL
light is on for no good reason (as opposed to invalid startup settings).
Power it on, rotate TIME/DIV back and forth leaving it in 5
seconds/division (the slowest setting), and manually set the other
controls for 1 MHz RBW and 100 MHz/division sweep with no video
filtering. The UNCAL light should definitely not be on at that point.
If it is, you can disregard it for the time being if everything else
works right.

I'll poke around in my 492 manual and see if anything leaps out at me.

-- jm

I tried it, it all works fine or at least seems to, but the "Uncal" LED is on.

I'm reluctant to open it and see where this LED leads to check the logic.
If it goes to the microcontroller and the port is fried, it won't help me much
anyway. Besides, everything else works at this point. I hope its not an early
sign of something else going to hell later on.

Thanks for your help so far.

SioL