XLERB

“I am holding: Safety sneakers, Sack of crackers”

I have ”Sorcerer” in the original box.

Fight on! K.F.G., as they say in my support group (Keep F'in Going!) I've been dealing with prostate cancer since November. Fighting the fatigue and other side effects. I've really appreciated the work you've done on Yesterday's News.

So… end of the story. Working, with the ancient floppy drive (now quieted down) and even the p-Code card working fine (so that wasn’t the cause of my problems). Quiet, seems to run cool enough. I won’t be running this system 24/7, by any means. (Wish I hadn’t given away the extra flat screen monitor we had kicking around the basement. That old CRT is heavy).

Will do that, thanks! .. This is a drive I bought from a guy as a spare back in 1988 or so and it’s been sitting in the basement in a box. The rails and related parts are right there to see. At least it works, unlike my original Shugart from the PEB combo sale from TI in 1984 or whenever that was. I feel like an archeologist. The guy I bought it from had a sticker on it saying “Dsk2” but it works as DSK1. I think he removed the jumper that made it DSK2.

I’ll defer to those who know more on this voltage regulator issue, but I do have a working disk drive so this is now a fully functioning spare system, albeit with a single ancient SSSD drive that makes some interesting sounds while in operation.

Thanks for the caution, I appreciate it. I’m going by the extensive discussion up-thread, and don’t plan to run this as my main box until I can make sure the cards aren’t running hot. I know it’s less than ideal, but I hope it will do. I’m counting on the fact that people have run BBS systems continuously this way without problems. I guess we have to live with the fact that TI made one of its more boneheaded decisions (out of many) to supply everything with 16v and 8v and then have the cards regulate that down. The other broken PEB will be my attempt to properly replace components on the original board, if I can manage to get them unsoldered. I have new capacitors and voltage regulators. That should occupy my next couple months. If that works, it’ll be the one that I feel comfortable using continually.

Yes! Clunking disk drive and all! Thanks to all who helped, especially jedimatt42 and insanemultitasker. IMG_2210.MOV

I still remember the “clunk” of the original Shugart drive that was my sole disk drive back in the day. I still have it in the basement - I should try it in this repaired PEB just to hear the sound again. (I mention the PEB so I won’t be off topic in my own thread 😇). By the way, it’s kind of funny that the Molex connector for the floppy drive (or whatever) has survived in these new power supplies. Kind of like how USB-A is still everywhere. I had a little trouble stuffing that hydra-headed bouquet of SATA and whatnot connectors into the PEB since I didn’t want to cut them off.

Wow! I imaged a new card with 3.1 and hit “Upgrade” and it went to 3.4 before I’d even seen this post. Rapid progress! And all my files got restored perfectly. One nice touch- In the “Files” tab on the webUI, I like the link-trail to “You are here” to replace the old ftp-style “one level up” button.

I got it all back together (managed to save the push-button switch with careful soldering and some epoxy glue to hold the joint securely), and it’s putting out the expected voltages. Still have to try my spare cards in it - 32K and disk controller for now. My only glitch is that the PSON pin didn’t seem to work properly, and I think it’s because the breakout board I bought has a built-in on/off switch that interferes with it. And of course that switch is inaccessible once I put the PEB back together. However, the “standby” pin seems to work when I wire it to the push-button switch. Except it works in reverse - the power is on when the push-button is disengaged, and off when it’s engaged, and only when the internal switch on the board is on. But that’ll do. Odd but seems to work. i kept the rocker switch from the new power supply and put it in the hole on the back of the PEB where the fuse holder used to be, after enlarging the opening to be a rectangle. I like the idea of being able to kill the power completely without unplugging it. Gee, I’ll miss the jet airplane sound when I turn it on now.

So following JediMatt42's lead, I am installing the ATX PSU and the breakout board in pretty much the same locations. I don't have a 3D printer so I cut up an old CD holder and put it where the plastic TI bracket was, and used a scrap of Plexiglas from a window repair to make a base for the breakout board. Now wiring the 115V socket and switch. That original push button switch is fragile - the lugs break off when I try to un-solder it. But I'll see what I can do. The fan from the new power supply had longer screws than the length or=f the TI bolts so I had to grind down the plastic on the corners of the fan housing but that will work. If the switch isn't usable, maybe one like this one - with a blue LED built in - would fit. But it might be hard because the old switch doesn't actually attach to the front panel, just protrudes through a hole.

Nice idea, maybe I will do that!

One other update: I’m still working on trying to replace the caps and voltage regulators on the other PEB circuit board, but even with generous applications of flux, it’s hard to get all of that solder off (and I’m sure the heat is frying the bigger voltage regulator since I heard it “singing”). But I’ll keep after that one (that’s my original rocker switch PEB, purchased during the great TI clearance in 1984 when my kids were all toddlers/preschoolers, so it kind of has sentimental value). All this fiddling around is keeping me busy during and after my radiation treatments for prostate cancer, which is a welcome distraction. (They’re finished, and I’m told I have an 85% chance it’s gone for good). But my wife wishes that I would get the tree trimmer out and get a new front door before I order any more electronic parts from Amazon and eBay.

Wow, that’s exactly what I was trying to do only better! I have the ATX power supply and I’ve removed the fan, transformer, and circuit board from my old-style PEB. I’ve also puzzled out the penciled-in color notations on the old schematic (yellow for -16VDC was especially hard to read). I’m at the point of thinking about grinding off those TI bolts, and I may end up doing that since I don’t have a 3D printer. I was hoping to avoid deconstructing the ATX power supply but the box it’s in is just too big to comfortably fit in the PEB. The breakout board I’ve ordered is very similar, and I was fixing to wire the push button switch to pins 15 and 16 of the 24-pin ATX connector as well. I’m going to study your method of fitting everything in. Absolutely impressive! Glad my questions sparked this project! One more comment - you could start a cottage industry with those 3D printed mounting parts!! EDIT: The ATX PS comes right out of its case, so I won’t worry about that. I might even be able to use the plastic bracket from the TI board with a few new holes drilled to hold in in just the right position. The breakout board can be mounted somehow, I’ll figure something out.

Thanks, Matt, this is all really great advice. I will try all of these.

Well, I thought I might also try repairing the power supply board as Plan B. But when I went to desolder the components, I discovered that TI used that military-grade solder that doesn't melt until it reaches 1000 degrees. They used the same thing in the RF modulators, as I discovered when I went to disassemble and use one of them to hold a composite cable I was making. It's more like welding than soldering. I may have to just cut the leads of the old capacitors and solder the new leads to the old ones instead of to the circuit board. And I don't know what I'll so with the two surface-mount voltage regulators. What a pain.

Wow! That looks exactly like a PC tower that my son left in our basement when he moved to Kansas. My wife made me get rid of all that stuff he left behind (including a bunch of power supplies). Oh well…

The other approach would be to start replacing components on the existing power supply boards, starting with the capacitors on the one that didn’t display fireworks, and see if it still blows fuses. I believe it was a p-code card that caused these failures, but I don’t know how to test any of the components on that. There are no obvious shorts. UPDATE: Ordered the capacitors and voltage regulators to replace the ones on the original PEB power supply board. Can't hurt to try. If that doesn't work then the AT power supply is plan B. I appreciate all the information and suggestions.

Thanks to everyone for all the information. I have a pretty fair idea of what needs to be done, but being a slow learner in matters circuit-wise, I want to be sure I’m being careful. Jedimatt42, your links to the datasheets should be very helpful. My fantasy that someone could make a step-by-step tutorial or video (similar to the 12v cooling fan instructions) is part of my insecurity but I may just need to trust myself and jump in. I have a spare 32K card and disk controller card that I can try first before I risk anything from my main setup with the TIPI and SAMS card.

I hadn’t mentioned the TIPI but that would be a huge concern for me. Thanks so much for all that information, it’s really helpful.

Good to know, thanks! I'm trying to stick with the existing firehose, but this is another possibility.\!

Hi all: I have a PEB with a fried power supply board (Diodes at least are shot, judging by the fireworks). I’ve been seeing and hearing that it’s possible to replace the big transformer and the PSU board with an ATX power supply, with the Mean Well PT-45 power supply mentioned several times. I’ve been scouring the threads (including Shift838’s massive tower project, which is far beyond my capabilities), looking for more information. I’ve also seen references in a couple threads to Tim Tesch’s way of connecting an ATX power supply, but can’t locate anything on that (apologies that I don’t know Tim’s handle on here). It seems (and I’ve gotten indications from Arcadeshopper) that the ATX voltages (+5v, +12v, and -5v, rather than TI’s 18v and 8v) can be used with TI peripheral cards and most others (except the HRD) without modifying the cards, since the cards will still handle the lower voltage OK. There was some controversy in this thread, but the prevailing opinion seemed to be that it can be done. But I haven’t been able to find any details about how this might be done, especially by someone who has done it. I’m pretty handy with a soldering iron and making physical modifications to devices, but my circuit knowledge is pretty rudimentary. Can anyone steer me to some more detailed directions, or even a schematic (beyond the PEB schematic)? I’d like to have a backup (that won’t damage my precious cards) so I won’t have to go back on eBay (and add another broken PEB to the growing pile in my basement) when something goes wrong - and I figure this may be of use to the community as working PEBs dwindle in the wild… Thanks!

Good to know!

I ran across the link to IRATA on another thread and got the CALL TIPI address from the website. It works great! The characters are really hard to read on my monitor (a composite-to-VGA adapter plugged into a stock console) but I’ll be anxious to see how it looks when I can finally get an F18A board. I’m really impressed with the speed of the terminal text and graphics and the fact that the TIPI USB mouse works with it right off the bat. I’m glad to get the key mappings, after fumbling around and trying out different key combinations for those PLATO keys for a half hour with limited success. Thanks, Thom, for all the effort that’s gone into this project. And I thought the pre-Y2K dates were actually kind of retro cool, along with the Control Data Corporation copyrights. I played Yahtzee first thing. The mouse works there, too. Nice.