At 12:56 -0700 5/3/13, Notgoing Totellyou wrote:
>I have the CPU card here and its missing a transistor.
>
>i can't find a replacement anywhere.
>
>Anyone have any lisa parts laying around?
>
>it reads : AMPS 4258 EBC
>
>you can see the spot behind it, it's missing .
>
\
Transistor Data Book edition 48, 1980
MPS4258 CRI, SPS, MOTO p 153 line 15 which says:
Silicon PNP low power
350 mw collector dissipation
V cbo 12 V
Collector max 800 mA
Hfe (gain) 15
I would recommend a very common 2N2907 as a replacement.
>From the picture it's not altogether clear that transistors Q1 and Q2 are
>supposed to be the same type.. A pretty common circuit uses PNP and NPN pairs
>close together. The pair to the 2N2907 is NPN type 2N2222, also very common.
>(I have a bunch of both here. Use dmcnutt at above off list with Lisa
>somewhere in the subject.)
A look at a working Lisa would be worth while. Anybody here ??
I also have no idea what the A in front of the very common Motorola MPS means.
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