68kMLA Classic Interface

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145B LCD recapped with tantalums
Posted by: PB145B on 2019-01-03 05:05:38
Never seen one of these done in all-tantalums before, but it seems to work great! The contrast drifting has almost completely vanished. Once I recap the inverter, it should be perfect. I also noticed that the overall image quality is better.

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Posted by: AwkwardPotato on 2019-01-03 10:06:16
Nice! That screen looks surprisingly sharp for a passive-matrix display.
Posted by: PB145B on 2019-01-03 10:11:42
Nice! That screen looks surprisingly sharp for a passive-matrix display.
Thanks! Yes, it does actually look really good. 
Posted by: techknight on 2019-01-04 19:19:10
Yea itll improve the image quality by an order of magnitude. Main reason is the passive matrix LCD requires a high driving voltage. around 40V or so for the sinusoidal signal to keep the crystals from developing a memory effect. If the caps are bad, it distorts that voltage and signal, seriously compromising the image quality. 
Posted by: PB145B on 2019-01-05 00:06:09
Yea itll improve the image quality by an order of magnitude. Main reason is the passive matrix LCD requires a high driving voltage. around 40V or so for the sinusoidal signal to keep the crystals from developing a memory effect. If the caps are bad, it distorts that voltage and signal, seriously compromising the image quality. 
Very interesting! I knew it improved the image quality by quite a bit, but didn’t really know exactly why. Now I do! 🙂  
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