Re: Fluke 77 ohms reading cal off

"Bob Urz" <sound@xxxxxxxxxxxx> wrote in message
news:1182134706_15407@xxxxxxxxxxxxxxxxxxxxxxxx


carneyke wrote:

You may have something causing the offset (bad solder connection). The
unit may have been damaged. The pot is for calibrating the 300 mv dc
range. As you have found it is the only adjustment. You either put in
an accurate 300mv or 3Volts and adjust the pot. Everything else falls
in to place (unless it has been damaged). Good Luck.

I took it apart and resoldered the studs for the input leads. I also took both
fuses out and used emery cloth on the contacts.
It now reads about .8 to 1 ohm leads shorted. My other 75 reads about .2 ohms
leads shorted. And yes i swapped the leads to see if it made a difference. (it
did not).

Voltage readings was about .1 volt difference between the two on DC volts. The
meter is not useless, i just cannot use it to reliably test very low value
resistors.

I wonder what could affect the ohms scale and not the DC volts?

Bob




For a digital meter, that 0.1V difference could be significant (unless you're
measuring an unstable source). What voltage range did you check on the meter?
If the lowest range, then I'll bet that's your problem.

--
Dave M
MasonDG44 at comcast dot net (Just substitute the appropriate characters in the
address)

Life is like a roll of toilet paper; the closer to the end, the faster it goes.


.

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