Sometimes knowing what something means is half the battle. Even better is when you can reproduce in real-time and actually *see* the fault on the screen. In this case, I have been unable to see any impact on the operation of the scope. I've been using it on my bench since 2012 as my main scope with this fault. It seems to be working perfectly! Model is an Agilent 54831B (now a 54832B)
That fails the trigger calibration on all four channels.
It reports for each channel (where X = channel #):
CHAN X trigger errors
Pred Delay
Looking through the files it creates from a cal routine for ASCII strings.
Framecal.dat has references to a "Predator Thresh Delay" and a "Predator Prop Delay"
It also creates a file called CalDebug.txt. In it is the following:
Starting ---- Pred Delay Chan 1 ----
PredII Delay:
DacValue 4047, measured value -13.353395 ns
DacValue 4044, measured value -13.341964 ns
DacValue 4041, measured value -13.351937 ns
DacValue 4038, measured value -13.339552 ns
DacValue 4035, measured value -13.332947 ns
DacValue 4032, measured value -13.353590 ns
DacValue 4029, measured value -13.354949 ns
DacValue 4026, measured value -13.360570 ns
DacValue 4023, measured value -13.336095 ns
DacValue 4020, measured value -13.349425 ns
DacValue 4015, measured value -13.347497 ns
DacValue 4010, measured value -13.336314 ns
DacValue 4005, measured value -13.343502 ns
DacValue 4000, measured value -13.341724 ns
DacValue 3990, measured value -13.343192 ns
DacValue 3980, measured value -13.344093 ns
DacValue 3970, measured value -13.341962 ns
DacValue 3960, measured value -13.345629 ns
DacValue 3940, measured value -13.362776 ns
DacValue 3920, measured value -13.340799 ns
DacValue 3900, measured value -13.350159 ns
DacValue 3850, measured value -13.340446 ns
DacValue 3800, measured value -13.356761 ns
DacValue 3700, measured value -13.336536 ns
DacValue 3600, measured value -13.353269 ns
DacValue 3500, measured value -13.349758 ns
DacValue 3400, measured value -13.326202 ns
DacValue 3300, measured value -13.334139 ns
DacValue 3200, measured value -13.346145 ns
DacValue 3100, measured value -13.345421 ns
DacValue 3000, measured value -13.349342 ns
DacValue 2500, measured value -13.342110 ns
DacValue 2000, measured value -13.349216 ns
DacValue 1500, measured value -13.351903 ns
DacValue 1000, measured value -13.340774 ns
DacValue 500, measured value -13.357989 ns
Predator Clock had 36 points
Not enough points to cover to -5.000000e-009
>>Time 6 Seconds
Finished ---- Pred Delay Chan 1 ---- FAILED
It seems to be pointing to a possible DAC failure. Interesting to note that as the DAC count decrements in an orderly fashion, the timing in ns does not. Anybody seen something similar? I do have some parts ACQ boards, my next step is to look at one of them and see just how many DACs on on the board.