On Fri, May 3, 2013 at 10:00 PM, Hardware Mack <[email protected]>wrote:
> do those cross reference to something radio shack might sell ? :-) > Website doesn't show 2907s, but it's worth checking your local store. Just don't expect the sales guys to know what they're talking about. Also check for 2N3906, that's also a PNP but may not be a well matched, haven't looked at specs. Mouser or Digikey will have them. If there are any better stocked electronics shops in your area they likely will, too - Fry's Electronics, maybe? > > 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. > > > -- -- ----- 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.
