I appreciate this is an old thread but . . . .
I went through this with my Beaver Partsmaster a few weeks back. Totally dead monitor but Heidenhain TNC355 control working fine - spare monitors like hens teeth and even ones with burnt screens fetching prices that sound like telephone numbers. I'm usually pretty good finding electronic faults but this one had me stumped. It was an internal switched mode psu fault but it beat me. Found a chap in the midlands selling drop in TFT replacements for iirc £450 - got one, dropped it in and everything was back working.
Then a couple of days later I got an email in response to a question I'd posed on a forum weeks earlier regarding one of the chips in the smpsu. He pointed me to a very similar (but different) part number & data sheet. In the data sheet was an application note, and darn me if the circuit wasn't practically identical to the Heidenhain monitor. The Heidenhain designer had oviously cribbed the circuit, which allowed me to fix the fault
Net result, I now have a spare monitor all wrapped up and tucked away inside the machine cabinet
I went through this with my Beaver Partsmaster a few weeks back. Totally dead monitor but Heidenhain TNC355 control working fine - spare monitors like hens teeth and even ones with burnt screens fetching prices that sound like telephone numbers. I'm usually pretty good finding electronic faults but this one had me stumped. It was an internal switched mode psu fault but it beat me. Found a chap in the midlands selling drop in TFT replacements for iirc £450 - got one, dropped it in and everything was back working.
Then a couple of days later I got an email in response to a question I'd posed on a forum weeks earlier regarding one of the chips in the smpsu. He pointed me to a very similar (but different) part number & data sheet. In the data sheet was an application note, and darn me if the circuit wasn't practically identical to the Heidenhain monitor. The Heidenhain designer had oviously cribbed the circuit, which allowed me to fix the fault
Net result, I now have a spare monitor all wrapped up and tucked away inside the machine cabinet
Andrew Mawson, proud to be a member of MetalworkingFun Forum since Oct 2013.