vintage computers

the-upside-down-capacitor-in-mid-‘90s-macs,-proven-and-documented-by-hobbyists

The upside-down capacitor in mid-‘90s Macs, proven and documented by hobbyists

Apple, capacitors, classic mac, Mac LC III, Macintosh, restoration, Tech, vintage computers, Vintage computing / /

Brown notes that the predecessor Mac LC and LC II had the correct connections, as did the LC 475, which uses the same power supply scheme. This makes him “confident that Apple made a boo-boo on the LC III,” or “basically the hardware equivalent of a copy/paste error when you’re writing code.”

Making sure rehabbers don’t make the same mistake

Why was this not noticed earlier, other than a couple forum threads seen by dedicated board rehabbers? There are a few reasons. For one thing, the rail was only used for a serial port or certain expansion card needs, so a capacitor failure, or out-of-spec power output, may not have been noticed. The other bit is that the original capacitor was rated for 16V, so even with -5V across it, it might not have failed, at least while it was relatively fresh. And it would not have failed in quite so spectacular a fashion as to generate stories and myths.

As to whether Apple knew about this but decided against acting on a somewhat obscure fault, one that might never cause real problems? By all means, let us know if you worked at Apple during that time and can clue us in. Ars has emailed Apple with this tremendously relevant question, the day before Thanksgiving, and will update this post with any comment.

By posting his analysis, Brown hopes to provide anyone else re-capping one of these devices with a bright, reflective warning sign to ignore Apple’s markings and install C22 the electrically correct way. Brown, reached by email, said that he heard from another hobbyist that the reverse voltage “would explain why the replacement cap” they installed “blew up.” Some restoration types, like Retro Viator, noticed the problem and fixed it pre-detonation.

Modern rehabbers tend to use tantalum capacitors to replace the fluid-filled kind that probably damaged the board they’re working on. Tantalum tends to react more violently to too much or reverse voltage, Brown wrote me.

Should C22 or other faulty capacitors destroy your LC III board entirely, Brown notes that 68kMLA member max1zzz has made a reverse-engineered full logic board schematic.

The upside-down capacitor in mid-‘90s Macs, proven and documented by hobbyists Read More »

40-years-later,-kontrabant-2-for-zx-spectrum-is-rebroadcast-on-fm-in-slovenia

40 years later, Kontrabant 2 for ZX Spectrum is rebroadcast on FM in Slovenia

adventure games, cassette, cassette tapes, gaming, Text Adventures, text games, vintage computers, zx spectrum / /

Cassettes are back, baby —

Celebrating radio waves, magnetic tape heads, and smuggled 8-bit computers.

–

Kontrabant 2 title image on ZX Spectrum

Enlarge / In 1984, the year 2000 was so promising, students made entire games promising to take you there.

Radio Student

Software is almost impossibly easy to download, distribute, and access compared to 40 years ago. Everything is bigger, faster, and more flexible, but there’s a certain charm to the ways of diskettes and cassettes that is hard to recapture. That doesn’t mean we can’t try.

By the time you read this, it’s likely that Kontrabant 2 will have already hit the airwaves on Radio Študent in Slovenia. At 9: 30 pm Slovenia time (UTC+2 in Daylight Savings Time), if you are tuned to 89.3 FM, hitting record on a cassette tape will capture a buzzing sound that will run until just over 50KB have been transmitted. If all went well, you can load the tape into your working ZX Spectrum or bring it to the Computer History Museum in Slovenia and use theirs to try it out.

<em>Kontrabant 2</em> box art.” height=”388″ src=”https://cdn.arstechnica.net/wp-content/uploads/2024/05/kontrabant3.jpg” width=”324″></img><figcaption> <p><em>Kontrabant 2</em> box art.</p> <p>Radio Student</p> </figcaption></figure> <p>It’s the 40th anniversary of <em>Kontrabant 2</em>, which was originally published by Radio Študent, both in physical copies and in similar over-the-air fashion. The game is in Serbian, as it was originally made for what was then Yugoslavia, for ZX Spectrums mostly smuggled in from Western Europe. Smuggling was something that lots of Yugoslavs did, in somewhat casual fashion, and it inspired <em>Kontrabant</em> and its sequel, text adventure games with some graphics.</p> <p>That I understand any of this is thanks to Vlado Vince, a Croatian/Yugoslavia native who wrote about Yugoslavian adventure games for a Spanish magazine, Club de Aventuras AD, and <a href=reposted it on his personal site. Kontrabant, which is text-only, has the player travel about the country (“and beyond!”) to collect all the parts of a ZX Spectrum. You meet famous smugglers from Slovene history, get a picture of yourself so you can leave the country for certain parts, and at one point obtain an Austrian porn magazine, which, in typical adventure game style, is later traded for something else.

A Kontrabant 2.” height=”720″ src=”https://cdn.arstechnica.net/wp-content/uploads/2024/05/kontrabant1.png” width=”960″>

A “Yugosaurus” in Kontrabant 2.

Radio Student/Vlado Vince

Kontrabant 2, from 1984, added the kinds of garish colors and flashing graphics that ZX Spectrum enthusiasts can recognize from a hundred yards away. This time you’re trying “to make your way to the year 2000 and to the amazing computers of the future,” Vince writes, and the game layers in political and social subtext and critiques throughout the journey. Also, the original Radio Študent cassette tape version had punk rock songs by “the Kontra Band” on it, which is neat as heck.

Kontrabant and its sequel were written by Žiga Turk and Matevž Kmet, students at the time, who are talking about the games and the times at the Computer History Museum Slovenia today. If you have a chance to visit that place, I think you should do so, given the impressive number of working vintage computers listed. Turk would go on to found Moj mikro magazine, a monthly computer magazine running from 1984 to 2015. He started the Virtual Shareware Library, which later became shareware.com (now a Digital Trends site I don’t quite recognize), and WODA, the Web Oriented Database. He’s now a professor of construction informatics in Ljubljana, Slovenia.

You can play Kontrabant 2 on the Internet Archive’s emulator if you can read or translate Serbian and understand the text prompts. YouTube lacks a playthrough of the game with graphics, though a later port to a native platform, the Iskra Delta Partner, is available in Apple-II-ish green-on-black.

40 years later, Kontrabant 2 for ZX Spectrum is rebroadcast on FM in Slovenia Read More »