Yes, the Protek 506 is discontinued, and Protek no longer gives support. Because it was my "good" multimeter, I kept it in reserve, so I was much miffed when it developed a fault after so little use. Because of that fact, I heroically soldiered forward, much like Don Quixote! Sigh.......Looks as though this meter is discontinued so you might have had your money's worth.
Unless there is something obvious on the board, it might be time to let it go.
I don't think I would trust it other than for very approximate readings.
The only things I've bothered to fix on a DMM (Fluke 83) were a slightly iffy display that just needed to be reseated and kept in place with epoxy, cleaning up the elastomer keypads or replacing fuses.
It's a real workhorse and is the only DMM I have that I trust.
by Aaron Carman
by Aaron Carman
by Jake Hertz
by Aaron Carman