Re: My 2465B has arrived + A5 Board leaky caps cleanup
Hey! Don't muck with the DAC adjustment, unless you are preparedtoggle quoted messageShow quoted text
to do a full calibration!
It is not supposed to be +1.25 and -1.25 volts, but rather a 2.500V span.
Sure, if you are a perfectionist, and diddle with the 10K reference
resistor values, and put in perfect opamps, it can achieve those values,
but that is not a necessary goal: 2.500V span when doing the calibration
routine is the necessary goal. -1.25 and +1.36V references that are *stable*
is the goal, as any errors in them get stored in the calibration constants,
and as such calibrated out, when the scope is calibrated.
Any tweaking, or replacement of DAC parts that you do will require a
full calibration of your scope. Why? Because you have no idea what they
were like when it was last calibrated.
If they were on the low (or high) side of spec when last calibrated, and
you adjust them to be right on, with a DVM that was on the high (low) side
of spec), they errors could add up to be wrong enough to perform poorly.
Hi Tom, thanks very much for your input. Bellow just a quick follow up.