Jump to content

BadGoldEagle

68000
  • Content Count

    1985
  • Joined

  • Last visited

Everything posted by BadGoldEagle

  1. BadGoldEagle

    Color Classic Restore

    Good to know. So that’s probably why mine won’t start anymore. I know I should have recapped it by now but that’s just one of the many issues it currently has.
  2. Ladies and Gentlemen, Today, I would like to talk about the rapidly decreasing population of working Quadra 9x0 (900 and 950) specimens. If no action is taken within the next 5 or 10 years, the entire specie will soon disappear. Although the exact cause of death is still unknown, most researchers have concluded based on the symptoms that failing PSUs play a major role in the evolution of this disease. Experiments have proved that transplanting PSUs from younger compatible individuals saved almost all affected Quadra 9x0s. At this point in time, only one did not survive the transplant, with all other attemps being successful. The goal of today’s discussion is to specify a new effective PSU transplant procedure to save the remaining individuals from extinction. Joke aside, my objectives are the following: 1/ To provide an easy solution/kit to replace the dying original PSUs. I’m pretty sure ALL are bad at this point and the lack of schematics makes repairing them uneconomical and replacing caps before failure proved to be not enough in my case. I will be using @GeekDot’s brilliant write up as a base for my mod. 2/ Make it so that there won’t be any drawbacks (which means creating a daughterboard to add back the square molex connectors as well as the monitor pass through feature) 3/ Make it silent. 4/ Meet or exceed the original PSU’s specs. But first, some additional background: The Delta PSU in the Q9x0 computers is a very strange animal. Because motherboard and CPU design changed so much in the last 29 years since the Quadra was first introduced, traditional modern PSUs don’t actually meet the old PSU’s specifications in some areas. While the original could happily deliver (back in its heyday) up to 33A on the 5V rail, modern high power PSUs struggle to output more than 25A. Some industrial-grade ATX PSUs on the other hand have to be compatible with old school systems, and that means that there are modern PSUs out there that are as powerful as the old Delta unit was. I plan on using a Bicker BEA-630 because it’s a modern, efficient, quiet (has a temperature controlled fan controller and operates most of the time without any fan at all) relatively small factor (ATX) PSU designed for 24/7 use (MTBF: about 20 years). I’ve found it for as low as 50 euros (which is really not bad for a brand new ATX PSU). There are unfortunately a few problems that need addressing: (ELECTRICAL ENGINEERING HELP NEEDED) - The 'minimum output current‘ problem. Industrial grade ATX PSUs usually have a 'minimum output current‘. This is a common problem for ATX bench PSU modders. Basically (if I understood it correctly), the rail won’t be able to maintain the proper voltage unless there’s a minimum load. In the case of the Bicker, the minimum output current for both 5V and 12V rails is 0.5A. Some people suggest taking one wire of each rail and wiring it to ground through a 5 or 10 ohm, 10 watt resistor. If my math is correct, I’d need a 10 Ohm resistor for the 5V rail (5V = 10 Ohm x 0.5A), and a 24 Ohm resistor for the 12V rail (12V = 24Ohm x 0.5A). Is this correct? If so the additional power consumption would be about 8.5W, right? - The 'there’s not enough pins' problem. ATX has 5x Ground and 5x 5V pins. The original PSU had 10 of each. Geekdot suggests to only populate every 2nd slot in the Q9x0 plug. In his excellent post, he proved that this arrangement worked and he was able to power up the Quadra. But with only half the pins, it probably halves the maximum current the board can take (‚probably‘ because we don’t know what the power repartition between the pins really is, so let’s assume it’s the same for each pin). Apparently ATX PSUs are designed so that each individual wire can deliver up to 6 Amps. So if I split one wire/post in two outputs, I can get about 3A max for each pin (assuming full load and without burning the PSU). Now the theoretical max. deliverable 5V amperage to the logicboard would be balanced across all pins and equal to 3A x 10 (# of 5V pins) = 30A which is almost the max. rated amperage (33A) of the original PSU for the whole computer. Of course, on the original Delta unit, not all 33A can go into the motherboard. So using one 5V pin from the Becker’s ATX 24 pin connector for two quadra 5V pins should be safe and will match or exceed the original specification. Any comments? I am no electrical engineer, so what is above might be completely wrong… - There are other small problems but they’re easily solvable so I won’t bother you with the details right now. I’ll have to learn how to use Kicad properly and will probably end up taking lessons. But hey, that might turn out beneficial for me professionally so I think this is a cool and easy enough first project. If you made it this far, kudos to you!
  3. BadGoldEagle

    BGE's take on the Quadra 900/950 ATX PSU Mod

    The real hard work would have been trying to fix these old beasts, not gutting them... but at least, like Geekdot said, it’ll run cooler, be more reliable and easily repairable in the future...
  4. BadGoldEagle

    Macintosh portable clutch mechanism

    Hi all I have bought a Mac Portable last week end. Since it was VERY dirty, I started disassembling it to wash the plastics. I used the Macintosh Portable service guide to take it apart. I washed everything using soap and hot water. I left the parts in water about 5 minutes to get rid of the soap completely. It's been a week now. But I CAN'T OPEN the display any more! I managed to disassemble the display once more and I realised the clutch mechanism was to blame. It doesn't rotate anymore... Now I know that I shouldn't have dipped the clutch mechanism in hot water like the other plastic parts but what can I do? I followed this guide: http://appletothecore.me/files/mac_portable_disassembly.php He washed the clutch mechanism and nothing happened...
  5. BadGoldEagle

    BGE's take on the Quadra 900/950 ATX PSU Mod

    @olliec420 Parts. 8 bucks would be a little too cheap for a complete mod... those boards will be BIG. Instructions/files will be free once I finish it. Hopefully I'll have a new schematic ready next week.
  6. BadGoldEagle

    3D Printed SE/30 ROM Clips

    Nice work. Now do one for the RAM slots that’ll cover the entire length
  7. Definitely following this one. I too had started listing the custom chips on the SE/Pluses, but you took a step further and that's impressive work! Keep it up @Kai Robinson It'd be particularly useful to reverse engineer that RTC chip. The ATTiny85 seems like a great place to start. The SE/30 uses the same chip and and it's generally what makes these boards impossible to repair once they've been bombed.
  8. BadGoldEagle

    BGE's take on the Quadra 900/950 ATX PSU Mod

    Thanks @mietek 22uF, 16V. Casing is probably C or D.
  9. BadGoldEagle

    BGE's take on the Quadra 900/950 ATX PSU Mod

    When you're dealing with tantalum caps, only replace the ones that are damaged. The rest of them (for now at least) are ok. I don't remember on top of my head what value that cap was and my 950 is currently buried under a pile of stuff... Maybe someone else can help? I think your PSU is what blew that cap.
  10. BadGoldEagle

    BGE's take on the Quadra 900/950 ATX PSU Mod

    @mietek sure thing... and that makes 10! Now, unless someone wants to buy 5 more, I'll stop the "pre-order" here. @Ton I feel your pain. It was pretty much the same thing for me but instead of RAM that was with the DOS card. And the damn PSU also tried to kill me (to be honest it was probably my fault). I'm really starting to think there aren't any original working PSUs left... And now, for the less fun part. A couple of weeks ago while casually browsing the web, I noticed that the MIC502 supplies aren't as high as I initially thought. I'll have to rethink the fan controller yet again (only for the 5th time). This on top of other life related issues, Apple ditching intel (which in itself almost caused me to fall into a depression), lead me to pause this project for a bit. I need to sort out the life stuff first, but when I'll get back to it (hopefully in the next couple of weeks), I'll most probably pay someone to design the new circuit for me. I just can't handle another failure emotionally. This time, I'd like to use a 555 PWM generator type of circuit, but I can't figure out which one (there's at least 4 different variants) to choose. I'd like it to be still temperature controlled, and to have a minimum speed threshold (duty cycle) of about 40% so that the fan can't possibly stall. More to follow...
  11. BadGoldEagle

    BGE's take on the Quadra 900/950 ATX PSU Mod

    I've had to revise the fan controller bit again... Big thanks to the guys over at eevblog.com for their help. Although this still hasn't been 100% approved/verified, it's looking pretty good now! We've mostly redesigned the LED controller circuit - Now we won't be frying op amps with voltages that are too high at the inputs (updated R8 and Vcc for U1). - I've switched to an LM393 (U1)as this is a proper comparator. The 358 wasn't. - Inverting Schmitt Trigger built-in (R5, R6, R11, R12). LED will light up at 84°C and will turn off at 79°C. Just like your engine waring light, it should never light up. If it turns red, please stop carefully and contact your nearest service center (i.e. me). FYI If you don't want temperature control just remove TH1 and replace it with a 10k resistor. If you don't want the Overheating indicator circuit, just leave R5, R6, R8, R9, R11, R12, U1, Q3 and D1 out... this is not recommended but the fan will still work without it. Leave those components out at your own risk. Edit/PS: I'll probably buy a bench supply and a breadboard to test this circuit before I send the boards to production...
  12. BadGoldEagle

    BGE's take on the Quadra 900/950 ATX PSU Mod

    Hallo Bunsen Thanks a lot for pointing out what it's called. The documentation will look a lot more professional now. Zur Info, diese Dinge heißt 'ne Durchführungstülle. En Français (I'm a french dude living in Germany after all...), ça s'appelle un oeillet ou bien un passe-fil... And yes, this mod is only compatible with Quadra 900/950s as they are (AFAIK) the only Macs with a 24 pin Molex Mini Jr (ATX motherboard) connector. In other news, I've had to scrap the previous fan designs (they weren't compatible with high wattage fans and wouldn't work with all PSUs...). It's now fully PWM and has a thermistor for fan control. A LED lights up once the thermistor reaches a temperature of 80°C/176F. It's still work in progress but it's lookin' good!
  13. BadGoldEagle

    BGE's take on the Quadra 900/950 ATX PSU Mod

    Proposed Comparator/Controller circuit: I had to take into account the different 2/3-pin fan control strategies (namely, PWM and Modulated ground) for the ATX PSU fan connector because since this isn't standardized, it has to work with them all. That's C1, R5-8 (on the right) and Op Amp #3. The other three Op Amps are used to compare the Potentiometer fan voltage to the ATX PSU fan signal. For those with Op Amp background, there's two comparator and one follower setups. Two power transistors Q2 and Q3 will effectively switch the two fan signals either on or off based on the table in the post above. I added a slide switch to disable/enable the comparison circuit (it disables the LM324's Vcc input and the circuit will function like before ie Potentiometer control only). For those who don't want to bother with this whole thing, just short 5 and 6 on SW1. You don't even need to buy the switch, I'm currently thinking about adding pads like on the IIc to short those pins: © Big Mess o'Wires Edit: For once, it was easier done than said. Kicad has some built-in solder jumpers! I'll double check everything again and I'll update the PCB.
  14. BadGoldEagle

    Radius Pivot SE/30 color monitor requirements?

    Can you post a picture of your card? Most SE/30 Pivots can only do greyscale. The color cards are pretty scarce. You should also check your ColorSync profile. Maybe it’s set to some odd greyscale monitor... My IIsi Pivot works on a wide range of monitors, including TVs with VGA inputs... so I don’t think the monitor is the problem here. FYI, there’s only one version of the IIsi Pivot (which can do color) and it’s “compatible” (to some extent) with the SE/30.
  15. Hi all. I couldn't sleep last night because of a damn mosquito that kept buzzing around my ears so I relocated to the adjacent room's floor (there are only two beds and a couch in my one bedroom apartment, one bed was already in use and the room with the mosquito had the couch and the second bed.) ANYWAY, my life is very exciting as you can tell. Obviously it was impossible to get some sleep so I did the next best thing: day (or rather night?) dreaming about some new Mac hacks. The SCSI2SD is great and all, but I miss the old hard drive sounds. I was thinking that it could be possible to record some sounds and then play them back. When you think of it, there are only two things that make noise: the heads moving back and fourth and the platters rotating. With the proper audio equipment, we could record some sample sounds (stepper motor initialisation if applicable, platters starting to rotate, platters rotating at a steady 3600rpm or whatever and also a couple of head movements). The first part of the said emulator would play a couple of mp3 files in some order: first stepper motor initialisation, then platters starting to rotate and finally platters rotating. That's easy. Any mp3 player can do that. Then for the actual head sound, we could use the LED activity light as a trigger. Every time the light flashes, that means the heads are moving, so if we play a couple of different head movements in a random order every time the light flashes, we should get pretty close to the sound an actual hard drive would make when used. As for the hardware part, there are some mp3 players for the Arduino, so I was thinking we could use one or two of them boards and then mix the two audio channels together. Add a speaker on top of that and that would be it. The best thing about this is that it would work with any emulator with an LED activity light (scsi2sd, scsi2cf, drem mfm emulator and so on...) So, what do you guys think? I'm not sure I can pull this off myself, so if someone else is interested in this project, let me know. I'm gonna do some more research on the mp3 player extension and see if it could play two mp3s at once... I'm also going to ask advice from some of my teachers. I hope they can help.
  16. BadGoldEagle

    BGE's take on the Quadra 900/950 ATX PSU Mod

    And the checks are done! Phew! I am still not particularly proud of my fan circuitry. I am currently thinking about upgrading my dumb controller to at least PWM. But I am also tempted to go with a full-blown temperature controlled circuit that reuses the PSU's built-in controller... but for someone with limited electrical engineering background like me, that's rather complex. Here are my (rather basic) system requirements: The minimum speed setting shall be controllable with a potentiometer or when possible trimmer. The fan speed while unit is in operation shall be regulated automatically based on the PSU's internal temperature. The actual fan speed shall be defined as the maximum between the temperature controlled speed and the minimum fan speed, whether the unit is on or not. The fan shall be able to run at a fixed speed if the PSU's built-in controller is not plugged in. Truth Table: FAN SPEED Cold PSU Hot PSU Quadra ON Always on and at minimum ATX controller OR minimum Quadra OFF 0 ATX controller* * May be used to cool down the PSU after the Quadra is switched off.
  17. BadGoldEagle

    Macintosh SE unusual screen pattern

    I remember there being a part on the CRT neck board that caused this when it failed. Don't remember which one though...
  18. BadGoldEagle

    BGE's take on the Quadra 900/950 ATX PSU Mod

    New pictures! Final checks are still in progress... but the new AC board design is now much "safer".
  19. BadGoldEagle

    BGE's take on the Quadra 900/950 ATX PSU Mod

    Hey there. You guessed the steps right . I'll come up with a more detailed guide later but that's pretty much it. At the moment I'm investigating the DC board clearances and I still have a few other small questions/issues before I can give JLCPCB the go ahead. I've never sent anything to Australia but I think it'll still be cheaper than having boards made yourself (of course you'll still be able to do that if you want... I'll upload everything to GitHub once's everything done and tested). PCB Way was WAY overpriced and it still costs 30 bucks to have the boards sent out of China with JLCPCB (since the minimum order quantity for ONE board is 5, that makes 10 boards minimum and copper is heavy!)... A set will weigh 120g. It'll have some light padding but hopefully that'll help you estimate the shipping costs. Tell me if you're still interested in getting a set. Back to the Quadra. Your 950 PSU exhibits the exact same symptoms as mine did after the recap. In my case, the 5V rail was causing this. I tried powering it on on its own with no load and there was 0v where there should have been 5. So don't worry, the logic board isn't to blame here. I had a professional PSU specialist look at the Delta unit and he couldn't find what was wrong with it... The diagnostic and the recap cost me a lot of money so I decided to cut my losses and start working on this mod.
  20. BadGoldEagle

    mac plus

    Give it a (small) whack on the left side. There are solder joints on the analog board (more specifically on the CRT coil connector) that often go bad. The display may briefly come back to life.
  21. BadGoldEagle

    BGE's take on the Quadra 900/950 ATX PSU Mod

    Apparently the voltage drop and added resistance are really negligible. This version of the board will replace the older design.
  22. BadGoldEagle

    BGE's take on the Quadra 900/950 ATX PSU Mod

    I have created a new version of the AC board with the filter at the input (instead of at the output). Any comments or remarks would be well appreciated. I'm concerned about the track lengths... The Neutral track (Net- (FL1-Pad2) ) is 13cm (5 inches) long. May be too much... What do you think?
  23. BadGoldEagle

    Mac Portable Help with Serial Number

    I'm afraid no one really knows. It doesn't seem to have anything to do with the name of place it was manufactured. I've seen Mac Classics with no text, with the actual production date (aka Chassis date) or with this "Serial Number" + letter text... The sticker on my Quadra 950 (made June '92) says Serial Number S...
  24. BadGoldEagle

    BGE's take on the Quadra 900/950 ATX PSU Mod

    I have good news. I was able to find cheap wires for both the logicboard harness and the AC input (AC board to ATX). 18AWG for LB: https://www.arrow.com/en/products/1430-18-1-0500-004-1-ts/cnc-tech-llc 16AWG for AC: https://www.arrow.com/en/products/1430-16-1-0500-001-1-ts/cnc-tech-llc Available in all colors, so the original aesthetic will be preserved. Black and red: 14ft each (that's 10x 40cm for each color) Rest: 2ft each -> price including terminals ($2.5 for 24): $16,52 Do you think it's too expensive? Another option would be to skip buying new cables altogether and re-use the original cables. Unfortunately for me, I'll have to order new ones as I kinda damaged the original harness... Technically the Becker also uses 18AWG for AC so you could theoretically use LB wires for AC. But for the price difference (80c), I'll sleep much better knowing that the AC wires are thicker. The 18AWG wires are a tiny bit smaller compared to the originals (16AWG), but they are more than enough (current wise) and they'll will fit better through the black cable tie thing. They're about 0.23mm smaller in diameter, which results in 5.5mm extra leg room! Awesome. The black cable tie thing is adjustable (it's just pretty much saturated with the OG wire config), so the harness will still be nice and snug. I'll update you guys with a BOM (list of parts) soon.
  25. BadGoldEagle

    BGE's take on the Quadra 900/950 ATX PSU Mod

    Don't worry @CC_333, I understand. I have been in almost the same situation for the past year . I thankfully found something recently that'll keep me busy and afloat. I'll keep the extra sets on hand until someone wants them. Don't worry, one has your name on it. In the meantime, if you want to try your luck with the old PSU, I would recommend using a power strip that has a switch on it (plug everything in and then switch the outlet on). That arcing sound when you try to plug it in "casually" doesn't seem right. In other news, I've had some issues with the AC board. As you can see from the previous pictures, there used to be an earth plane pretty much everywhere but on the DC side of the relay. Apparently this can cause issues and it's best to remove it. Thanks to alumbrado on r/vintageapple for suggesting it. I have since done more research on the matter and it is indeed not recommended to have one. Here is the new current design (v0.6): The minimum distance (clearance and creepage combined) between AC and DC is now 10mm. Apparently (and according to a post on this thread), the minimum safe distance for 240V AC (in this case 240V is critical, not 120V) is 5.5mm so there shouldn't be any issues. I am now sure that I over dimensioned pretty much everything. The minimum clearance between the AC tracks (Neutral, Phase, Earth) is now 4.5mm. But we're talking tracks, not plated holes, so this is well above the 'acceptable distance' of 1.6mm. I've also had to take another look at the original board because depending on the type of load (inductive, resistive...), snubbers may be required. Delta didn't use anything to protect the relay from the monitor, so it should be fine without it. I am still having issues with the cables for this mod. I've found the original specs: https://www.wontex.com/products_3_b.php?gid=7 but I can't find new cheap ones that aren't bigger... I am now considering using 18 or 20AWG. More to follow.
×