Apple Lisa I/O board diodes

[Adrian Graham]

On 19/02/2016 01:02, "drlegendre ." <drlegendre at gmail.com> wrote:

> FYI, I get a 403 on that link.
> 
> As for the diode, unless the leads are seriously rotted, why not just make
> a +note+ of it - and leave it alone? It's a hermetically sealed package
> (glass+metal, right?) and not likely to have suffered in any way, aside
> from the cosmetic issue.


Fixed, I don't normally put things in the root of my webserver and forgot
about the permissions. The diode does still check out with my DMM, but it
looks plastic to me which is why I mentioned it - it's not your usual 1N4001
glass type and I don't have another I can compare it with since my other
Lisa is a 2/10 and the I/O board is different.

A

> On Thu, Feb 18, 2016 at 6:51 PM, Adrian Graham <witchy at binarydinosaurs.co.uk
>> wrote:
> 
>> 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?
>> 
>> 
>> 

-- 
Adrian/Witchy
Binary Dinosaurs creator/curator
Www.binarydinosaurs.co.uk - the UK's biggest private home computer
collection?