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Re: AppleColor RGB all-red display



Michael J. Mahon wrote:
> D Finnigan <dog_cow@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/transistors-bjt-single/1376376?k=c2688>