Re: AppleColor RGB all-red display

[Grent <grent3@gmail.com>]

On Oct 18, 1:41 pm, dog_...@macgui.com (D Finnigan) wrote:
> Michael J. Mahon wrote:
> > D Finnigan <dog_...@macgui.com> wrote:
> >> The story continues:
>
> >> Yes, it was a bad transistor for the red channel. It tested differently
> >> compared to the blue and green transistors. Using better light, I could
> >> also
> >> see scorch marks on the PCB from where I'd apparently made a short
> >> circuit
> >> the other day.
>
> >> Next step now is to find out what kind of transistor it is, and get a
> >> replacement part.
>
> > Glad you found it.
>
> > I'd guess a high voltage (50-70v) medium beta NPN. After replacement you
> > may need to adjust the red brightness ("screen") and contrast ("gain") to
> > get the colors right again.
>
> I just researched the transistor number, and it appears to be a standard
> part: C2688.
>
> <http://search.digikey.com/us/en/cat/discrete-semiconductor-products/t...>

Yes thank you for posting the information