68k Soft/Hard Power and ATX conversions . . .

[directive0]

It would be in your best interest to read a datasheet. I say "a" datasheet as active components (2n2222, 2n****, TIP120, LM555, etc) sometimes come in different sizes, or packages by different manufacturers. Most of the time these different packages share conventions such as operating envelopes and pin arrangements. Its important to ensure you are looking at the datasheet referring to the package you have. With that in mind, there should be a small metal tab somewhere on the circumference on the cylindrical enclosure. Using this tab as reference you can check the linked datasheet to determine which leads are which.

:beige:

 

[olePigeon]

Ooo, perfect. Thanks! That's exactly the one I have. Now on to solder and tape stuff. (I really need to get heat gun + heatshrink)

 

[techknight]

I havent seen a TO-5 transistor in a looooong time.

 

[Trash80toHP_Mini]

I thought you said your brain didn't do TTL, not backwards compatible from microcontroller tech or some such? )

@ directive0: there's something disturbingly Edgar Allan about your avatar . . . what is it?

 

[olePigeon]

Hmm. Doesn't seem to change anything. My power supply is either on or off when I flip the switch. :?:

 

[zuiko21]

Strange... Please double-check all connections. You did remove the jumper previously used for firing up the PSU, right? Click here for the IIci's PSU pinout -- it's the same as the IIvx, Q800 etc.

Also, make sure that the metallic enclosure of the transistor isn't touching any other contact -- some models have the enclosure connected to the collector. If it's in contact with Ground, will likely show the symptom you describe ("always on"). Ditto if the power button on the IIci is at the "locked" position...

If all of the above fails, you may try to disconnect the end of the 10K resistor from the /PFW line, and connect it temporarily to GND -- PSU should stay OFF all the time. And if you connect that resistor to the violet cable, PSU should go ON -- as long as the hard power switch you installed is ON, of course

@Trash80toHP_Mini: I haven't though about the PS/2 translating microcontroller because it's a bit beyond my capabilities... and all my compacts use ADB anyway. The problem is not the schematic, but programming it 8-o

The compact's video is 60 Hz vertical too... Level switching between TTL and VGA is certainly the easy part here, but the horizontal frequency is 22.254 kHz, way below most multi-sync monitors would accept -- they usually go from about 31 kHz and up, covering at least basic 640x480 VGA (31.5 kHz).

However, back in the day there was at least one monitor capable of displaying these frequencies and some "modern" video modes: the NEC MultiSync 3D, if memory serves, accepted 15-38 kHz -- from CGA to early "super"-VGA, with things like EGA or even Macintosh 13" (67 Hz) in the middle. But they seem very hard to get now :'(

Anyway, if modern technology is allowed there are nowadays some relatively cheap scan converters which take a CGA or EGA signal and output a regular VGA one -- basically they digitize the input signal into some sort of VRAM, which in turn is displayed at VGA rate. Not sure, though, if they'll accept the slight difference on horizontal frequency from EGA (the closest one). According to this page, the "official" range is 23.5-25.5 kHz, thus unsuitable for compacts (but OK for 12" RGB). Maybe with some tweaking...

 

[Trash80toHP_Mini]

I was thinking that tt or or one of the other microcontroller generation of hackers might have suggestions . . .

. . . if you build it . . . the ProtoPCB . . . they will come. [)] ]'>

Besides, the schematic and source code are BSD licensed and available from the creator of the 24th Anniversary Macintosh

To this TTL generation electron plumber, the inverse function of that board ought to be a doable project for one of the gang. Having the 128k/Plus/MicroMac_68030 sitting on the desk with KVM hooked up to the switch, sharing the wireless KBD and Mouse of my main workstation 'puters has been on the long-term wish list for a while now . . .

. . . bonus points for adding ADB output to that board! }

Like I said, Compact video adaptation is a long way off. Modern technology is pretty much all we're talking about for anything but the PSU Conversions. But the scan conversion route is something I didn't think about when I posted: UNDERClocking a Video Card??????

< tangent mode >

Just re-read that thread and realized that I've got to buy the crystal can you suggested for that RCPII/IIsi VidCard. THX! I also need to finish noodling out the spreadsheet for calculating the different timings for the SuperMac Spectrum/24 resolution hacking project . . . more crystals . . .

. . . now where did that thread get to . . . :?:

Does anyone have a link to the video timings for the VGA inputs on 480p, 720p and/or 1080p? I came up w/zilch the times I searched. :-/

< /tangent mode >

Meanwhile, I did a rough listing of the hacks near completion/in progress/planning/parts acquisition stages . . . came up with approx. fourteen involving desktops-n-towers, four of those are stalled by, or patiently awaiting, ATX conversions. The DOA DA needs one too . . .

. . . so many hacks . . . so little time . . . :-/

 

[olePigeon]

Strange... Please double-check all connections. You did remove the jumper previously used for firing up the PSU, right?

Jumper? I haven't removed any jumpers from the ATX PSU. I must have missed that step. Not even sure where to look.

Also, make sure that the metallic enclosure of the transistor isn't touching any other contact -- some models have the enclosure connected to the collector. If it's in contact with Ground, will likely show the symptom you describe ("always on"). Ditto if the power button on the IIci is at the "locked" position...

I covered it in kapton tape. Shouldn't be touching anything.

 

[Trash80toHP_Mini]

The jumper setting was news to me as well, I don't recall seeing it, could have overlooked it as well. :-/

 

[directive0]

@ directive0: there's something disturbingly Edgar Allan about your avatar . . . what is it?

Its the Kestrel from Escape Velocity!'

:approve:

 

[Trash80toHP_Mini]

I like it, but of course to my twisted little brain it looked more like . . . erm . . . someting like . . .

. . . dunno, maybe the top view of a four sided, horizontally oriented Klingon Roulette spinoff from Poe's Pit? }