Jump to content

lisa2

6502
  • Content Count

    105
  • Joined

  • Last visited

Recent Profile Visitors

607 profile views
  1. With all that corrosion damage on the CPU card edge, makes me wonder what condition the socket on the MB is in. Did you replace the MB socket?
  2. This behavior is not normal. Like you stated, both MEM cards sound OK, but maybe possible that one of the memory slots in the MB is bad and only one the slot RAM cards is actually working. The POST would not know better and just test the one card it "sees". May also be an issue with the CPU card in it's MMU section.
  3. The KryoFlux would not be much help here. The Twiggy is 62.5 TPI drive, and I don't know of a "standard" drive that will interface with the KyroFlux that is also 62.5 TPI. Standard 48 TPI or 96 TPI drives will not be able to position the head correctly to read the Twiggy formatting.
  4. My guess is that these are for EMI compliance, I don't think that if you jettisoned these parts it would have much effect. Many-many serial designs ( including the Tecmar Lisa four port card) do not use filters like this and work fine. The Macintosh does have these also, on the schematics they are listed as "DEGLITCH PACKS", and the SE the silkscreen on the Logic board says "FILTER". Rick
  5. Yes, it appears that Bourns have EOL these last year, but Mouser still has them in stock ( the RoHS version ): https://www.mouser.com/ProductDetail/Bourns/4120R-601-250-500L?qs=izxORn%2FBzZchDGI8%2FT4C4Q%3D%3D Rick
  6. These parts are not just resistor networks, they are "RC Networks T-Filters" AKA "EMI/RFI Filters" My modern 2/5 and 2/10 clone boards use Bourns PN# 4120R-601-250/500 More info here: https://www.bourns.com/pdfs/601.pdf Hope this helps. Rick
  7. I have worked on dozens of these boards, and the capacitors have never been the problem for me... Try replacing the voltage 7824CT regulator U1 ( at lower right corner of the board ), an indication that this is failing is that the the resistor R1 will be burned/cooked (and should be replaced also). This is a very common fault on these boards as they age. Good luck!
  8. I am in Chicago, maybe some day we could create a Trans-Atlantic Appletalk network, I can setup my Lisa as a file server..
  9. Another neat thing the gatorbox can do is tunnel an appletalk network between to gatorboxes using tcp/ip. Note: The configuration does work best with classic macs, You must configure it using local talk, and the configurator does not support open transport. also be aware that the early models have no rom or flash and must booted via a sftp server.
  10. As was said, it does not matter if the cabling is LocalTalk or EtherTalk. But note that MacIP is only supported up to System 8.6, System 9 users can not connect using MacIP. Your SE will not support System 9 anyway, so for this case it is moot.
  11. I have done this before. This will work fine, just make sure you don't plug in the "lisa lite" board ( and you won't have a floppy). Rick
  12. Dog Cow, Great! I would be happy to test your project on the Lisa when you are ready. Thanks, Rick PS. I have a copy of the source code for MacPPP 2.01 if it would help you, PM me.
  13. Great! Please keep working on this. I would like to connect Lisa's running MW+ ( 1MB RAM and system 6.03 ) to a serial PPP server. My problem is MacPPP works best with System 6.07 and better (that the stock Lisa can't run) and eats up a lot RAM ( Lisa has 1 MB RAM, but MW+ uses over 256K, leaving less that 700K usable). Also, the stock 5Mhz Lisa runs a little slower than a Mac, causing issues with some PPP clients internal timing. I need a very small, fast serial PPP client that will work with System 6 or System 5. Something like Marina for 68K... Thank
  14. Absolutely! The Macintosh II ( 1987 ) supported as many displays at you had slots to put display cards in ( in this case qty. 6 ).
  15. Just as some background info on the 1.2A Lisa PS, this is a quote from the Sun Remarketing Lisa DYI guide circa 1990: "When the original 1.2-A Lisa 2/5 supply is used with an internal hard drive and a Macintosh XL Screen Kit (described at the end of this chapter), audible transformer ringing results, horizontal retrace lines become noticeable, and a slight screen flicker is introduced. Installing the 1.8-A Lisa 2/10 to Mac XL supply eliminates all of that." I experienced this first hand over 30 years ago. My point is that even when working to original specs, the
×
×
  • Create New...