do those cross reference to something radio shack might sell ? :-)
Thanks for looking at that! Charles On May 3, 2013, at 9:58 PM, Blair Aakre wrote: > Q1 and Q2 are part of the oscillator circuit. They are both identical 2N4258 > PNP transistors according to my CPU board schematic. > > -Blair > > > > On May 3, 2013, at 5:09 PM, Hardware Mack 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] >>> 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. >>> >>> >> >> -- >> -- >> ----- >> 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. >> >> > > -- > -- > ----- > 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. > > -- -- ----- 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.
