[Coco] Buyer beware

[Mark McDougall]

Bill wrote:

> And
> there is a piece of something rattling around inside. 

A note for the future - if something is rattling around inside, it's 
probably _not_ a good idea to turn it on! All you need is for a piece of 
metal to be lying across the wrong two tracks, and you'll never get the 
smoke back in...

Whenever I receive some vintage equipment, the first thing I _always_ do is 
open it up and give it a visual inspection. Disassemble into modules - 
unplug all connectors, unmount all circuit boards etc. Re-seat all the 
socketed ICs. And unless it's pristine (LOL) I give everything a good clean 
- dust off the circuit board, clean the plastics thoroughly etc.

Only then do I re-assemble and power it up (before screwing it all back 
together).

Not only does it look a lot nicer, you'd be kicking yourself if you 
powered-up that long-awaited retro computer that you could _finally_ afford 
and see the boot screen for 2 seconds before it fizzled out and smoke 
billowed out the cooling vents - only to open it up and see an old paper 
clip lying across the power pins of the only custom (non-socketed) IC on the 
board! :(

> I know I'm not the only one to fall for something like this, and I "puts
> down my money and takes my chances" along with everyone else. 

As Neil & Steven said, "untested" and "as-is" mean "doesn't work". You just 
need to learn the lingo! ;)

On the plus side, if it is a minor problem and you manage to fix it (and 
it's evident that there's plenty on the list willing to help), you'll get a 
lot of satisfaction over the fact that _you_ got it working, and that the 
seller actually lost out! ;)

As for your specific problem, if it's more than badly-seated IC's, it's 
_generally_ either RAM or an easily replaced (though less easily diagnosed) 
passive component. I'd be surprised if it were ROM or 6809/6883/6847 - but 
then again I'm not familiar with the failure modes of Cocos...

Regards,

-- 
|              Mark McDougall                | "Electrical Engineers do it
|  <http://members.iinet.net.au/~msmcdoug>   |   with less resistance!"