My CPU board (for a Mac XL) reads: 419 2 N 5771
Both Q1 and Q2 are identical. Hope this helps. On Friday, May 3, 2013 6:09:44 PM UTC-4, Notgoing Totellyou wrote: > > thank you for that great information! > > Can anyone look at their lisa cpu board and let me know what you have in > that spot? > > Thank You! > Charles > > > > On May 3, 2013, at 6:01 PM, Doug McNutt wrote: > > > 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. > > > > > > -- > > > > Fe++ > > // \ > > Fe++ Fe++ > > | || > > Fe++ Fe++ > > \\ / > > Fe++ > > > > -- > > -- > > ----- > > You received this message because you are a member of the Vintage Macs > group. > > The list FAQ is at http://lowendmac.com/lists/vintagemacs.shtml and our > netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml > > To post to this group, send email to > > [email protected]<javascript:> > > To leave this group, send email to > > [email protected]<javascript:> > > For more options, visit this group at > http://groups.google.com/group/vintage-macs > > > > Support for older Macs: http://lowendmac.com/services/ > > --- > > You received this message because you are subscribed to the Google > Groups "Vintage Macs" group. > > To unsubscribe from this group and stop receiving emails from it, send > an email to [email protected] <javascript:>. > > For more options, visit https://groups.google.com/groups/opt_out. > > > > > > -- -- ----- You received this message because you are a member of the Vintage Macs group. The list FAQ is at http://lowendmac.com/lists/vintagemacs.shtml and our netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml To post to this group, send email to [email protected] To leave this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/vintage-macs Support for older Macs: http://lowendmac.com/services/ --- You received this message because you are subscribed to the Google Groups "Vintage Macs" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/groups/opt_out.
