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Bolle

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  1. My bet is you won't be able to set this up correctly by using just the pots.
  2. Any reason for opting for one of the more expensive (and still chinese) hot air stations? For soldering down tantal caps you are better off using just a soldering iron. For removing them I am against using hot air as well, others might argue that because it is not correct by the book to just clip/twist/wiggle them off the board. Heat transfer into corroded solder spots is extremely bad and I end up with caps that start to boil and pop right into my face before the solder even thinks about melting (still happens with proper preheating and everything...) The health risks are just not worth it for me to maybe weaken a solder pad by mechanically removing caps. If you want to use hot air get a 858D (have used one for years and it is still going strong) and invest the money you saved in a decent soldering iron, good flux, dry cleaner, wick and good (leaded) solder. EDIT: oh and instead of digikey you might want to consider reichelt.de - they ship to sweden and shipping should be cheaper as well than digikey
  3. Use tantals as they are the easiest to work with. What soldering gear do you own to begin with?
  4. Bolle

    Extra confusing Classic checkerboard

    On most Macs the CPU reset line is controlled by the sound IC. Some models use the DAC to check if the clock signal (and maybe the 5V supply) are stable and once that's the case the chip will get the whole system out of reset. Default state is that the CPU reset is held low by the sound IC. There should be a pullup resistor somewhere on the CPU reset line. See if you can find that and check if it actually works. I would not recommend jumpering the reset line right to 5V as you might send a lot of current through wherever it is tied to ground. EDIT: Not totally sure and don't have my Classic at hand right now to check but it looks like there is one of the Sony soundchips on there. Those can go bad (or weak) resulting in glitchy reset behaviour. I think Larry Pina described that you can add a second pullup resistor somewhere in the 1k-10k range right to the sound IC to get around the issue while maintaining a working reset switch.
  5. Those two NEC chips are the VRAM. The eight DRAM ICs are the built in RAM.
  6. Not really. I studied communications engineering but my everyday job is only slightly related to anything electronics anymore For reading that ROM I simply hooked it up to an Arduino and wrote some code to cycle the address lines through all possible combinations and reading the data lines dumping the raw binary output to the console. Next up I will hook up the analyser to the PROM and see when (or if at all?) it is used. I would imagine it patches something into the original ROMs early in the boot process. I wonder why if it even does anything as I already have the upgraded HD floppy ROMs in my Mac II (which should be identical to the IIx ROMs I think) and the IIx adapter does not have any logic on it and does not need any ROM patching at all to work with the PowerCache. While the analyser is out I will see if I can figure out the address decoding PAL - shouldn't be too hard as it is combinatory - leaving the most fun part of the probably registered GAL as the final challenge.
  7. And the ROM on there: aaaa55555800002e24436f7079726967 ..UUX...$Copyrig 68742031393931204461795374617220 ht.1991.DayStar. 4469676974616c2c20496e632e004e7a Digital,.Inc..Nz 00020280000020000080000008084e7b ..............N{ 000241fa0008f01040004ed600000000 ..A.....@.N..... 00000000000000000000000000000000 ................ 00000000000000000000000000000000 ................ 00000000000000000000000000000000 ................ 55aaaa5550f800aa500200020b564552 U..UP...P....VER 53494f4e20322e300452534620000452 SION.2.0.RSF...R 44472000044d4b4220000c3800010cb1 DG...MKB...8.... 6634487a003621df002c11fc00030cb1 f4Hz.6!..,...... 21fc408000500cb421fc000000400cb8 !.@..P..!....@.. 42a7f01740002ebc58008607f0170c00 B...@...X....... 11fc0003012f59894ed12f002f08206f ...../Y.N././..o 000a20100c80f000400067280c80f01f ........@.g(.... 4c006632f02f4c00001058883f6f000e L.f2./L...X.?o.. 00162f4800123f6f00080010205f201f ../H..?o....._.. 508f4e73f02f4000000458882f48000a P.Ns./@...X./H.. 205f201f4e73205f201f2f3800304e75 ._..Ns._../8.0Nu 00000000000000000000000000000000 ................ 00000000000000000000000000000000 ................ 00000000000000000000000000000000 ................ 00000000000000000000000000000000 ................ 00000000000000000000000000000000 ................ 00000000000000000000000000000000 ................ 00000000000000000000000000000000 ................ 00000000000000000000000000000000 ................ 00000000000000000000000000000000 ................ 00000000000000000000000000000000 ................ 00000000000000000000000000000000 ................ 00000000000000000000000000000000 ................ As always with rare gear you should take a soldering iron to it before even really using it Reading the ROM was a bit of an adventure as those old small PROMs are not supported by my chinese ROM burner:
  8. As an 1/8th German. I have arrived here at your site on request from one of your members. My interest is the Mac SE/30. I am trying to upgrade it. I have a twin Spark adaptor and are looking for a Daystar Turbo 40 card. Last time I looked  in 2009 the SI cards were priced between $2 and $40 US, they are not now. I am trying source a card at a reasonable price. I am a collector. I have six Mac computers SE/30. G3 tower, G4 tower, G5 tower, two early 2009 xserve's and an ipad Pro

  9. BTW: The II flies with a 50MHz PowerCache. Did not yet try the Turbo040 but 40MHz 040 with 6 Nubus slots does sound like something everyone should have
  10. As there was some interest in that trading post thread over here I thought we might gather some information on the Mac II and the Daystar adapter here. One difference this adapter has compared to all other Daystar adapters is that it (besides going into the CPU socket) plugs into the MMU socket that's only found on the Mac II. Reason for that is that most of the address bus of the logicboard is cascaded behind the MMU like shown in the MC68851 user manual: For the accelerator to be able to access the whole logicboard bus it has to connect right to the physical address bus (behind the MMU) as well as to the logical address bus (between 020 and MMU). The adapter itself looks pretty straight forward: All MMU control signals are disconnected as 030 and 040 upgrades don't need those because they have built in MMU features. Most of the bus control signals connect straight through between the accelerator slot and the 020 socket. There is a tiny 4096 byte PROM on the adapter (still gotta find a way to read it - it looks like my TL886 does not support the AM27S29 or any of the similar DIP20 512*8 ROMs. Next to that we have a PAL20L8 that's doing address decoding to generate the chip select for the ROM - that's going to be easy once I find time to hook up the logic analyser. The trickiest part is going to be the GAL16V8 that looks like it's generating address/data strobe signals to translate between the different busses (physical/logic on logicboard and accelerator) Any takers for some guesses what the GAL might be doing exactly? *looking at @joethezombie*
  11. Bolle

    Mac II Battery Issue

    If you have one of the later logicboards it needs to be recapped. Got a picture of your board?
  12. What happens when you set it to 256 colors? It's possible the image in the installer was made for 256 colors and gets thrown off with thousands of colors.
  13. Bolle

    Macintosh SE/30 with Radius Card

    As said machine will need a recap and most probably one of the video address multiplexers/shift register/counter ICs is bad (UE8 most of the time but the others in that row go bad as well)
  14. Bolle

    Macintosh SE/30 and lines

    RAM SIMMs not having contact would give you slow chimes though. The ROM is the culprit here.
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