From: jjhudak@gmail.com   
      
   On Sunday, December 24, 2023 at 11:22:45 AM UTC-5, legg wrote:   
   > On Sun, 24 Dec 2023 05:01:17 -0800 (PST), "Peter W."    
   >  wrote:    
   >    
   > >If you had done your Consumer Reports back in the day, you would have found   
   that Sharp has notoriously frequent display issues. With this in mind, you   
   might contact Sharp for suggestions. They know their reputation, and are   
   counting on the consumers    
   not knowing.    
   > >    
   > >Peter Wieck    
   > >Melrose Park, PA   
   > Peter,    
   >    
   > I don't buy microwave ovens, I just fix them.    
   >    
   > This model of microwave R21LV has a few variants    
   > which have been mfred since before Y2K.    
   >    
   > It's service manual illustrates a panel with a    
   > completely different display on the control board,    
   > possibly even LED, vs the LCD variety present here.    
   >    
   > I've got nothing but respect for Sharp stuff. My    
   > pocket calculator from the 90s has been through the    
   > laundry twice, without permanent damage. It has an    
   > early type of LCD display.    
   >    
   > I've seen LCDs that have obvious damage/discoloration    
   > and flakey elements before, but never something that    
   > was permanently, uniformly dark.    
   >    
   > There's no carbon press strip to degrade, just 15    
   > solderable in-line pins.    
   >    
   > I would suspect the controller chip, or its ceramic    
   > resonator, but the chip seems to be performing normally.    
   > The unit runs.    
   >    
      
   "All necessary wiggles being delivered to solderable pins" - Not sure what   
   this means so I'll make an inference: All the LCD segment lines change state   
   appropriately?  Checked voltages on all segment pins at the same time (with   
   perhaps a 16 line digital    
   analyzer)?  Bias voltage on the LCD correct? If all true then the LCD is   
   dead.     
   Does this model have a separate LCD controller chip or does it use a micro   
   with a number of DIO lines?   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)