Re: C128 problem

From: Terry Raymond <traymond20_at_gmail.com>
Date: Thu, 25 May 2017 14:38:52 -0600
Message-ID: <CAEFCF-p_K0=61WA-X-gEcWPtb-aDL+XJkijpET8jU0NzJS6=Zg@mail.gmail.com>
Hi Thanks gives me a starting point.

Terry Raymond

On May 25, 2017 12:50 PM, "Francesco Messineo" <francesco.messineo@gmail.com>
wrote:

> On Thu, May 25, 2017 at 9:11 PM, Mike Stein <mhs.stein@gmail.com> wrote:
> > I assume the fuse does not blow when the supply is disconnected from the
> > computer? Voltages OK?
> >
> > Relatively unusual that a chip would blow the fuse; I'd check the caps
> > first, especially any tantalums.
>
> I have a 6569R1 that instantly blows the fuse on a C64 (this chip gets
> +12V and +5V from a separate 7805 inside the C64).
> But I agree, it's best to first test capacitors. Even a bypass ceramic
> could get shorted.
>
> Frank
>
> >
> > ----- Original Message -----
> > From: Terry Raymond
> > To: cbm-hackers@musoftware.de
> > Sent: Thursday, May 25, 2017 2:38 PM
> > Subject: C128 problem
> >
> > Hi,
> > My C128 has a problem with blowing the fuse in the power source what
> could
> > cause this?
> >
> > This C128 is dead, black blank screen, C64/C128 modes won't work, nothing
> > She's completely dead.
> >
> > I was told to check all logic chips, can this be done with a meter or
> logic
> > probe, does this require and voltages on Logic chip pins?
> >
> > I found jnfo on how to build a simple logic probe, maybe a different post
> > later since this
> > Has something to do with TTL/CMOS LOGIC OR LS logic, very interesting.
> >
> > Terry Raymond
> >
>
>        Message was sent through the cbm-hackers mailing list
>


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Received on 2017-05-25 21:01:20

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