Apple Lisa I/O board diodes

Forbidden You don't have permission to access /LisaIOBoard.jpg on this server. 2016-02-18 22:51 GMT-02:00 Adrian Graham <witchy at binarydinosaurs.co.uk>:

> Hi folks, > > 'Decaying battery' panic led me to unearthing my Lisa 2/5 to check the > state > of the batteries on the I/O board since it hadn't been out of its box or > powered up since 2005. Fortunately the damage is very minimal and is only > restricted to track discolouration and external rotting of one particular > diode which I can't find mention of on my schematics. > > Anyone with a 2/5 care to check their I/O board for me please? The diode is > D8, just above the battery location. It's in the board in such a way as to > make its markings pretty unreadable in the pictures I took before cleaning, > but it's the only white diode in the machine and I'm guessing it might be a > 5.6V 1N4734A based on what I can see. Fortunately it still works for now, > 0.7V voltage drop. > > Pic of the board before cleaning is at > http://www.binarydinosaurs.co.uk/LisaIOBoard.jpg > > Cheers! > > -- > Adrian/Witchy > Binary Dinosaurs creator/curator > Www.binarydinosaurs.co.uk - the UK's biggest private home computer > collection? > > >