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techknight

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  1. If you use a relatively modern copy of a virus program for Mac, I believe it covers all the viruses. like an OS9 early OSX virus protection software for PPC. Scrub your collection, and you dont need any of that crap. Then you do not have to worry about it. Its not like any modern viruses targeted for those old machines are coming out, and if it did, nothing will see it anyway.
  2. techknight

    Help Setting up Retro68 on OS X

    Yea, I am not a C/C++ developer so yep. Wooosh.
  3. techknight

    Help Setting up Retro68 on OS X

    Woooosh
  4. techknight

    SE/30 PDS Adapter Epic Blunder

    You may get lucky and only have lost one of the ABT573 ICs. They seem to buffer what goes in and out of the bus on that card. Thats assuming SIZE0 doesnt run all the way back up to one of the custom ICs, without a schematic you wont know unless you trace it all out.
  5. techknight

    Macintosh SE/30 Sony PSU not working

    Troubleshooting will likely be needed here. If changing all the caps didnt help, then you will need to find out what failed. Not everything fails due to "caps", as power supplies fit that exception. its likely a failed component. Diode, resistor, maybe even an IC. Luckily the schematics are available.
  6. Yea, probably. You accidentally connected signal lines together that arnt designed to be connected in that manner. I am highly surprised you did not kill the ADB IC in the SE. But then there is also the factor of which I have no idea if the keyboard even worked prior, so theres that.
  7. techknight

    SE/30 PDS Adapter Epic Blunder

    LOL. Yep, I am pretty daft. Didn't pick up on it. Anyways regarding the topic, I have blown up so much electronics over the years its not even funny especially when I was younger. I never take it personal anymore otherwise it will eat you alive. Not to mention the time I tried to stick a Nubus ethernet card into an SE, Backwards. It fit, but did it work? um.... you dont want to know. ESD, reverse polarity, experimenting, you name it. I always just chalk it up "in the name of science" for me when I do it experimenting or attempting to repair something. My "E.B Club" is probably larger than the participating members in this thread combined. As for the card, its likely the IC is dead. As Bolle had mentioned the different voltages getting applied to logic lines, Easiest thing to do is grab a DMM and check those lines on the card between VCC and Ground, it likely shorted one of them out to one of the voltage rails. Either VCC or ground. Especially if you hold up one of the /SIZ lines, it'll fail to boot. The power supply has no PTCs in it, not these days. One of the voltages rails was grounded by the mistake, and it tripped the built-in overcurrent protection. Once the comparator latches the D-Flop, there is a capacitor that has to discharge before it clears the latched state, This is all built into the SMPS controller IC. As long as voltage is applied, the timing capacitor stays charged, and the D-Flop stays latched. So before the timing capacitor can discharge, the main input filter capacitor has to discharge, and since there is essentially no load, this can take a long long time. All it takes is a fraction of a microsecond to damage a semiconductor. MUCH shorter than the duration at which the protection will latch in, Trust me. That single pulse from the power supply that is outside the specs is enough to blow the junctions of logic gates. you drive a transistor above or below its maximum limits it will damage it. Most datasheets have an "Absolute Maximum Ratings" section you can take a peek at which shows the limits, as well as the duration of what can happen before a chip cannot tolerate it, Just to help gauge things into perspective.
  8. techknight

    SE/30 PDS Adapter Epic Blunder

    Actually, Yes I do. Google doesnt find anything?
  9. techknight

    SE/30 PDS Adapter Epic Blunder

    What is an E.B. club?
  10. techknight

    Death chime and Simasimac on Mac SE/30

    Its not going to be UE8, or any one of those ICs, I guarantee that. the "stripes" is the initial state of the VRAM at the time of powerup. Each brand of VRAM have their own initial states thats why different brand VRAM used in the various SE/30 boards power up differently when the video circuits are not initialized by ROM. The fact that you have those stripes and they are being displayed properly without being broken up, rules out 90% of the video circuit including UE8. However, that does NOT rule out the PAL ICs entirely, as one of them is responsible for generating the System RAM R/W timing. You need to start looking at address/data/chip select lines between the GLU/CPU and the VIA/SCC/SWIM, RAM Muxes, etc. The 74F258 muxes are known to fail on these boards, you could start there. Also a persons depiction of Fast and Slow chimes could be subjective, without a sound sample I cant tell if its truly slow or fast. Fast chimes could be caused by any one of the VIA's control lines to the CPU, or its interrupt and control lines back to the peripheral ICs. Either way, when I used to work on SE/30 boards, 100% of the death chimes were always caused by RAM access issues. RAM itself, the traces, or the ICs involved therein. But you experiences may be different. the system not being able to access the SCC, SWIM or SCSI would not cause death chimes, it never has for me. Even the ASC, but if it could not access the ASC, you would not get sound at all. The fact that the ROM is not initializing the video means its crapping out really early in the boot process, and thats 99% RAM with the SE/30. If anything, and I mean anything at all is holding up the bus, you would get nothing. no chimes, no nothing. The fact that you get Chimes, and especially if those chimes are clear, rules out the bus.
  11. techknight

    TAM Not Booting Up

    its a little fuse that popped on the LCD itself.
  12. techknight

    SE/30 display crashing to black with a raspberry sound

    The problem with this stuff is you need to know how to do electronics troubleshooting and have the proper tools, as well as knowing how to use those tools. Electronics are different in the fact that you cant physically "see the electrons" moving around and doing there thing, unlike cars and other things in life, which makes understanding electronics really difficult to grasp for some people because you cant put your finger on it. With this kind of stuff, you have to think 4th dimensionally. The glitches are being caused by power supply dropouts. What causes power supply dropouts? Tons of things. feedback circuit issues, loss of the oscillator, overcurrent/overvoltage erroneous detection, tons of things. It could even be down to a faulty noisy transistor causing the oscillator to stop and start again. Could be capacitors. if you had a good superfast scope with 1 shot capture enabled, you could probably pick up the spike or dropout on the power rails when it happens. Tracing the source of the problem would be difficult.
  13. techknight

    Problem with FloppyEmu

    1.44MB support was the reason why I wanted to change out the IWM with a SWIM and then patch the ROM with the SE FDHD disk driver, but I never got around to it. I did by the rominator though. I dont know the differences between the SE and the Plus ROM to see if the Plus would boot an SE rom natively or not. If not, only thing possible would be patching .Sony
  14. techknight

    LC 475 Chip Corrosion: When Standard Methods Fail

    With a single repair, Sure. if your doing dozens, then maybe. I have one at work which I use from time to time, I dont have one personally because as mentioned, I cant justify it personally. But I already have one at work, so...
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