Eurostile and SECAM vic 20!

Unfortunately I just couldn’t find any color TV or monitor from the early 80s…

I also plan on getting a printer, a 1541 and a WiFi modem

This was my first "difficult" CRT repair (which isn't saying much; I didn't need to adjust purity or anything crazy like that). TLDR: bad -20V rail due to open resistor; three weeks of diagnostics could've been saved by just measuring voltages on all neck board connectors.

• Unit looked like it does in the picture. From inexperience, I assumed it was at normal output levels with vertical retrace lines visible.
• Methodical multi-stage shotgun recap didn't fix.
• Reflowing all flyback, neck board, and PSU-side solder joints didn't fix.
• I suspected the vertical blanking pulse, but it looked completely fine coming out of the vertical IC all the way through the sandcastle into the TDA3505 IC Pin 10.
• I discovered the SCREEN pot was cranked high (the retrace lines always show up at some point with that much push), likely by the former owner to compensate for the real fault: extremely dark screen; contrast and brightness couldn't compensate. I put the SCREEN pot back to its normal position, leaving the picture erroneously dark.
• I inspected the tube's neck; saw all three lights as anticipated.
• I measured the heater pins; proper voltage.
• I decided to play with some solid colors using a C64, alternating between the BASIC 2.0 screen with a black background, white background, and red background. On the black background, after 2 seconds, the screen actually came up to normal picture (the text was at proper brightness). When I would then switch to red or white, I would get normal output for about 1 second maximum, before the darkness would reassert.
• I considered that the tube might be tired. However, that brief flash of normal operation made it seem like it was perfectly capable and being held down. I measured the cathode voltage swings between a black vs. white screen; on a good unit, it swung +30 volts, but on this bad one, it moved about 2V. So the drive wasn't even properly really reaching the cathodes.
• I then thought maybe the beam limiter was erroneously engaging. However, the bad unit TDA3505 contrast pin (19) stayed identical regardless of output (the good unit swung from 3.6V to 3.3V on white). So it didn't seem like the TDA3505 was meaningfully even triggering that logic.
• To clear the TDA3505 once and for all, I tested the outputs of pins 1, 3, and 5 (RGB) and they were totally healthy.
• Since those signals were seemingly good, I moved to the neck board to see if they survived all the way up to there, or if a common rail was causing an issue across all three channels. The three transistors all tested great (11.4, 12, 125).
• I then tested connector M7. All good, though +12 V read +11.5 V. Still, the neck board transistors were all testing fine.
• I then tested the collector resistors just to try and locate where the fault was coming in, common to each channel (R714, R715, R716, biggest ones on the neck board). They showed hardly any change on a black vs. white screen (VOM, probes on each side of the resistor). When I would flip black to white, I noticed the voltage try to increase before falling back, which was consistent with the actual visual result (black works at normal output; white flashes for a second and then the fault reasserts).
• So I then tested connector M6. The -20V rail came back +6.3V. I moved back to earlier in the -20V rail at R636 on the main board; same. So I went all the way back to the flyback transformer, Pin 4, which was OK, but the fusible 1.5 ohm resistor right in front of it (R484) had failed and was completely open.
• I checked out the diode/capacitor in front of that in turn, but they seemed OK, so I presume R484 may have failed due to age, or some unknown event in the unit's past life.

I feel like an idiot for spending so much time on this, when just checking the rails at the neck board connectors would've immediately exposed the fault.

My understanding of why this tanked the brightness: there's a couple places after the TDA3505 where the channels intersect or reference -20V. The first intersection goes back into TDA3505 Pin 26. The second hits the main board transistors' emitters. With R484 dead, the -20V rail floats to +6.3V.

From here, it gets a little complicated for me, since I'm still pretty new, so any elucidation here would be great for learning:

• The cathodes need more current to display a brighter screen, which means the voltage goes down in tandem with current going up, for a given quantity of electricity. This is facilitated via the -20V rail as the "drainpipe". The failure of this behavior was totally evident from some of the probing I did above. With -20V floating at +6.3V, that current can't be pulled. The drain is clogged.
• G1, on the schematic, also ties into the -20V rail. With +6.3V, it can't fully switch the beam off, so cranking the screen pot up to remediate the darkness immediately pops the retrace lines. (But I'm not sure about this one; on my good 1902A, the retrace lines also become visible in the upper one-third of the pot, which is pretty consistent with the bad unit).

Now I just need to summon the courage to loosen the clamp screw to correct the small screen tilt...

I decided to make a start on its restoration so I got my boxed VIC-20 on the bench this week. Before turned it on I checked the power supply, the plug and the fuse and measured the output 4.7V DC. It came out fine. The cursor froze once, but after a restart all the keys, sound worked and the original joystick worked too, which I didn’t expect.

About 20 minutes in it just switched itself off. Power LED has gone off and black screen. I turned it off and on again, it came back and a couple of minutes later it went off again. So I unplugged it and started the strip-down.

The board (250403 Rev D) is cleaner than I expected. No burn marks, no water marks, nothing obviously resoldered. The one odd thing is this black wire running across it, from one of the outputs over to the power side. I’m not sure it was fitted at the factory.

Has anyone seen this wire on their VIC-20? And does the switching off sound like the power supply to you, or something on the board? I’ll post updates as I go.

TLDR – Today I’m relaunching my site https://amigasource.com/. For the past 25 years I’ve been endlessly cataloging Amiga related websites and now the site is even better! The current link count is 5431 of 99.95% pure Amiga goodness. So hop on over and enjoy!

Thanks

Scott P

More…

In celebration of the site’s 25th anniversary and in conjunction with a complete rewrite of the codebase, I’m happy and proud to reintroduce AmigaSource.com back to the Amiga community.

Born from the ashes of the once great Amiga Web Directory, the site is an attempt to hand catalog every Amiga website on the web. At least that’s the plan. The current count is 5400+, of which I’ve been tirelessly working on revalidating 4900+ and the initial cataloging 3500+ of those. HOLY CRAP is this quite a task!! I should have started this part a DECADE AGO!!! LOL! Feel free to help out by clicking on the SUGGEST EDIT link.;-)

The BEST part is at least they‘re in the main database for you to search and explore. No 2nd page google/bing non related ai slop Amiga links found here. Just 99.95% pure Amiga love found on EVERY PAGE!!

Now as you can imagine in the past 25 years A LOT has changed in Amiga land. Back in 2001 my initial category count was just 37. Today it’s grown to over 130. OUCH I know, but I’m working on this. Any suggestions in this department would be GREATLY appreciated. Turns out in 2026 there’s more to the Amiga than ever!

The other big change is the countless number websites that are no longer with us. Over the years I’ve still been adding and cataloging them, via https://archive.org/, so their efforts have not been lost to the passage of time and their stories and knowledge will still live on. I think these pages are the TRUE jewels of the site and the direct link to our Amiga heritage. Go search for a site created in 1985. I dare ya! ;-)

The bottom line… I’m a Amiga/Commodore guy, the site’s BETTER than is been for the past 24 years and I’m happy with it! I just hope someone else out there finds my little contribution to the Amiga community useful too!

Well that’s about it. For now please tread kindly to all the GLARING mistakes you come across. I’ll get to them… eventually. The site is STILL undergoing last minute tweaks and more features will soon be added. If you have any click the ‘Let Us Know’ link.

Thanks, enjoy and help spread the word!

Scott P

To learn more, please visit:

https://www.kickstarter.com/projects/darkagesoftware/eldemar-a-new-first-person-rpg-action-game-for-the-amiga

Eldemar takes you from the forests around the village of Cerro down into ancient crypts and burial mounds, and on to the city of Nharuk. You explore, fight, talk to the people you meet, trade with merchants and solve the puzzles the land throws at you.

The design draws on two classics we grew up with: the open exploration of The Legend of Zelda on the NES, and the first-person action game Doom. Combat is real-time, so corridors full of skeletons need your faster reflexes.

The engine is hand-written in 68k assembly, built for AGA and RTG. No ports, no emulation layers. Eldemar is a native Amiga game, designed in 2026 by veterans of the demo scene.

What makes it possible... Only Amiga!

Hi everyone, I’ve built this C64 emulator and would love to hear what you think. It was an experiment to test a programming language I created, called GEKO...

I keep my C64 collection on a PC and got tired of the extract, convert, copy, mount loop, so over the past while I've been building a Norton/Total Commander style file manager where a disk image just opens like a folder. It all started when I got my C64 Ultimate in May, so I built support for that great machine in it too.

What it does right now:

• D64 (incl. 40-track), D71, D81, D80, D82 and DNP open as folders and are writable. Copy files in and out, rename with F2, scratch with F8, reorder directory entries, undo with Ctrl+Z. G64 and T64 open read-only.
• The directory shows in real PETSCII the moment you land on a disk, without mounting it.
• Search across disk images, including ones still packed in a zip, 7z or rar.
• Launch in VICE (or another emulator): mount the disk, or inject a PRG straight into memory.
• Ultimate 64 / Ultimate-II+ / C64 Ultimate: it finds the device on your LAN, lets you edit disks on its storage and run PRGs on the real machine.
• Directory art: a small editor to draw logos and separators in the C64 font and drop them into a directory.
• Keyboard first, everything works without the mouse.

Version 1.0 is a rewrite of my earlier 0.9 beta as a native app: about 3.5 MB instead of 63 MB, no .NET runtime. Windows 10/11 x64 only, installer or portable zip. It isn't code-signed, so SmartScreen will ask you to confirm.

It's a beta and there are rough edges. What I'd really like to hear from people here:

• Disk images that open wrong or that it refuses (odd track counts, non-standard directories, copy-protected stuff).
• Whether the PETSCII directory preview matches what you see on real hardware.
• What you'd want from a tool like this that it doesn't do yet.

Download and screenshots: https://retrocommander.dev/download

Please note: using the tool requires creating an account (e-mail + password). If you don't like that, don't bother.

Happy to answer questions in the comments.

I'd like to write content on the C64U, which publishes directly to a html-only website and can browse other websites made by the C64U. The content would be compatible with most ancient browsers also, so you could maintain something like a basic page or blog.

I couldn't find anything that performed exactly how I wanted, so I thought it would be a relatively straightforward process to use AI to generate most of this stuff which is based on very old tech.

Turns out it's actually a pain in the arse, and a couple of months later I have something that allows you to write text with basic markdown style formatting, and it can upload files directly to my server, with a few simple php scripts which convert things to html content.

However, it will need a lot more work to be a practical, functional and a decent user experience.

Before I continue working on it, I'd like to make sure there isn't an easier way, because I'd happily jump ship and use someone else's tools.

Have I missed something? Are there already tools out there which can achieve what I'm after?

Again, the goal is write on C64U -> publish online directly from C64U -> browse my own and other sites from C64U.

For some this might seem like a waste of time and I get that, this is not a commercial or practical product. This is simply a hobby project which is reaching a level of complexity I didn't anticipate.

Was the VICmodem the first million-selling modem? I've seen that assertion without evidence, so I dug into it. In this blog post, I estimate how many units Commodore built and I share my methodology. Spoiler: If you own serial number 124308 or higher, I'd really like to see a photo. https://dfarq.homeip.net/how-many-vicmodems-commodore-sold/

I'm producing a set of artwork used to promote important computers. Sadly, Commodore's adverts and cover art wasn't attractive enough to hang on a wall. Then I discovered this post from nearly a decade ago. Does anyone have a better quality version? This one appears to be scanned from a two-page spread and is missing a central band from the image.

What is the best site for disposal of these copied C64 games?

Chapter 9 devlog of my C64 Polychrome Raycast Game engine. PETSCII sprites learn to flip as 1 Mhz of p(doom ) takes over the C64 in 3D polychrome and with PETSCII powered emergent sound effects generation.

Check full devlog vid before the p(doom) eliminates it forever:
https://www.youtube.com/watch?v=Yb9bQubac1M

. . . this is how it started in CHristmas of 1983.

VCF Swap Meet: Sat. Oct. 17 - Wall, NJ

https://vcfed.org/vcf-swap-meet/

Has anyone bought this build from mini-itx.com? I'm very curious about it, I love retro things and would like an actually cool mobile computer but I can't find any reviews or people talking about it. I don't plan to do any gaming on it, it would be mainly used for music production.

Thanks in advance.

On the lower corner of my c128, there appears to be some sort of strange discoloration on the case. I’ve already tried wiping it down with some household chemicals but no change. I’m more curious as to what could have caused it. I do know that the key caps can stand for a cleaning though as I just got the keyboard itself functioning properly with carbon paint.

Dunno if you all are active on facebook groups, but theres been developments in the "RAD SCPU Testing" group of a raspberry pi 3 married to the RAD expansion unit, providing a recreation of the SuperCPU 64. Its not perfect, but its looking really good and he's working on an FPGA version for the Commodore 64 and 128 along with another guy providing the necessary MMU unit. Cool stuff.