Bram Jacobse

Tinkering CD Players & Digital Audio

CD 100 With Repair Attemps

by · Published · Updated

This CD 100 is still not working after severeal repair attempts by others  , If i could have a look.

First check

  • LM317 for +5 volt gets very hot.
  • LM337 for -18 volts gets very hot.
  • Found repair on two traces
  • Capicitors have been replaced
  • found a dead wasp

 

 

Processors are working 😉

 

 

 

 

Repaired tracks

150 µf on modification board placed wrong way around

Laser is working Peak 82.7

found something ,  misaligned lightpen

Added some measurement wires

Tweaking the laserpen

Some progress , after some  hours  adjusting the lightpen and tighting the screw , without moving the lightpen 😉

There is something strange this player has a SAA7010 / SAA7020 with modification board ,  instead of a SAA7011(M4290a)  / M4281  , Replaced the SAA7010 with a M4290A still trouble reading TOC , why the eye-pattern looks good enough. okay, lets check the data lines from SAA7011 to the SAA7020.That is looking funny. Looks like a schort circuit to me

Here its is small wire between the Pins 26 & 27

 

After removing the short between pin 26 & 27  , Table Off Content reading is as normal again..:-) , and there is Audio !!

 

“It arrived and works perfectly! Thanks again for your service!”

“Hij is binnen, en werkt perfect! Nogmaals erg bedankt voor je service!”