HP54520 Logic Trigger Problem

[mwbarth36]

Update.  The board from RamondMack arrived on the 22nd.  Thanking him for packing it so well, as the package looked like a Tank had run over it.  The board was not damaged only due to excellent packing job. 

I first changed the 3V battery as it measured 0.78 Volts.  Next, I put the three atten's from the old board into the same channel locations on the new board.  After a brief warmup period, loaded the Default values as required, and started the calibrations procedure.  Everything passed with not a problem, including the 'Logic Trigger' calibration.  I monitored the AC Cal. output as the LT Cal. was in progress, and the signal does not change at the 582 count.  This is where the old board would terminate the Cal. and put up the error message (Failed). 

So, I now have the scope operating 100%.  Would still like to know exactly what the problem is with the old board, but not going to put much more energy into it unless I can somehow get hold of the schematics for the scope, or the meaning of the error code. 

Thanking everyone for their Input!

[RaymondMack]

Sorry to hear about the box getting beat up. USPS is usually pretty careful with light weight packages.

I'm happy the replacement mainboard came out unscathed and worked. It's always satisfying to see something get fixed and even more so to have helped out.

I've been procrastinating with repairing my 54542C. But hopefully I'll do it this weekend.

If you're interested, Leo Bodnar makes a little pulser that can be used to calibrate the input rise time.

https://eevblog.com/forum/projects/yet-another-fast-edge-pulse-generator/

I plan on getting one of them to calibrate my inputs after replacing the attenuators.

[MarkL]

Glad to hear the replacement board worked instantly!

But I do hate unsolved mysteries, so if you ever get back to it please let us know...