Slightly out of topic question

[cyborg0 at GlobalEyes.net]

yknow, you *could* try oven cleaner to dissolve the epoxy.. Some of the new
oven cleaners seem like they could etch hardened steel...I had a run in with
some stuff that ate paint AND good chrome plating off of the broiler of my oven
and turned some of the plastic fixtures to goo...
wow!
Rob

Jay Martin wrote:

> Usually removing a cartridge while the unit was on would cause the power
> supply to spike.  The C64 used a 7805 type regulator that does not contain
> protection for this.  What usually happens is the power supply suddenly
> decides to oscillate at around 8 volts.  This then fries most of the RAM
> chips (they didn't have much protection in those days).  You will probably
> have to replace the power supply and the RAM chips.  But try just the power
> supply first.  Believe it or not, even though the power supply is
> non-fixable (unless you got a real early one) and has a "brick" of epoxy
> covering all the components (causing the eventual demise of the regulator
> due to it's inability to dissipate the heat) they then put a FUSE in there
> (in the middle of the epoxy).  It **COULD** just be that blew..but you will
> most likely not be able to replace it (unless you have some solvent to eat
> the epoxy away.)
>
> Try the power supply and then the RAM chips.
>
> Jay Martin
> P.S. I speak from a ton of experience, I used to work as a repair tech for
> Commodore equipment.
>
> > -----Original Message-----
> > From: gronda_a at starnova.it [SMTP:gronda_a at starnova.it]
> > Sent: Monday, October 05, 1998 4:53 PM
> > To:   synth-diy at mailhost.bpa.nl
> > Subject:      Slightly out of topic question
> >
> > Hello, I've got an old Commodore C64 (that it's also in some way an
> > analogue synth!) to repair.
> > Does anybody know what get fried pulling off a cartridge while the unit
> > is powered on?
> >
> > Thanks.
> > Andrea