Occasional musings.
PREAMBLE I found myself in need of a bit of mental stimulation over the past few weeks, and wanted to take on a project that would really tax the old grey matter. Something in the universe must have aligned because at the same time I was reading about the Chat64 cartridge developed for the Commodore 64 by Bart Venneker and Theo van den Beld and an idea struck me. Now this post is going to be long…
Straight-off-the-bat, this is not a review of the HD-64. Rather, this is a fairly lengthy description of some modifications I made to the HD-64 installation to better suit my needs, and why. I remember, not all that long ago in fact, stating categorically, that as far as getting decent quality video output from the Commodore 64 was concerned, LumaCode was the only worthwhile solution. I said I…
At the links below, I have declared blind AB Audio tests comparing an original MOS 6581 SID chip with modern SID replacements: Test 01 - 6581 SID versus ARMSID Test 02 - 6581 SID versus Nano SwinSID b Anticipated Questions What is this? It's very simple: an AB audio test allows you to directly compare two or more audio samples. For these tests, I've recorded outputs from an ARMSID, a Nano SwinSID…
A few weeks ago I was watching this YouTube video and thought to myself, "I gotsta get me one of them!" If you haven't watched the video, nor have any intention of doing so then, a brief synopsis goes like this: for 36 minutes Adrian Black extols the virtues of the all new (ish) Des-Test MAX software, brought into the world by programmer, Matthew Desmond which Adrian describes as " the biggest…
Before I bought into the Ultimate II+L for my Commodore 64, my go-to for 1541 disk emulation was a Pi1541. And even though I no longer need the Pi1541, I still like to have it - not least as a backup and for occasional use with my test board. There are many variants of the Pi1541, but the one I liked was the Pi1541 Zero with Epyx Fastload. This one: My original Pi1541 hat As you can see, this hat…
This right here is one of those things you hope you never need for your Commodore 64, but the moment you do, you'll be really glad you went to the bother. Sold by retro8bitshop , the Space Saver Pro is currently retailing for 17.95 EUR (at time of writing). Factor in shipping and PayPal fees and my wallet took a 29.41 EUR hit which converted to 26.12 GBP. Now for a 30cm (11.81 inch) cable, that's…
Please note: this article was published in June 2024. Since then, the RF Replacement V2 discussed here has become obsolete and unavailable. As of December 2024 it's been replaced by V3 (the ARRGH EFF OFF ), therefore this post is now out-of-date. It's finally here, the battle nobody's been waiting for: a head-to-head fight to the death between my JaF Sandwich RF Mod Replacement, and Mark…
As I have mentioned many times in the past, one of my goals with my Commodore 64 projects was to have a machine consisting of 100% new parts. Mostly for the fun of it but also just plain old curiosity, to see if it could ever be done. Well today I get one step closer to that goal as the J-CPU by Jani Laatikainen finally arrived. This is a direct replacement for the original MOS 6510 CPU originally…
Ok, it's been several months since the last update and a lot has changed. First, let's recap. In the first part of this series in which I redesign my JaF64 RF Modulator replacement to become the all new JaF Sandwich I explain why the hell I would want to add an archaic RCA Jack to my design and this can be summarised in one word: LumaCode. In the second part I dedicate some time to dealing with…
Some things really try my patience. And patience isn't something I have an infinite reservoir of in the first place. This here is one of those things. So let's recap. In part one I set out my reasons for wanting to add an RCA Jack to my JaF64 RF Modulator replacement. In part two I got a prototype of my new build, now renamed the "JaF Sandwich", to elegantly pass a LumaCode signal from the…
It strikes me now, and I'm pretty far down the line, that this particular project will only be of use to a very small number of (discerning) readers. Specifically, those with an interest in the Commodore 64, that also have a Kawari Mini VIC-II replacement, that also have an interest in getting LumaCode from that Kawari Mini, that also have a 250466 motherboard in a reproduction C64C case , that…
Rage Against the Machine The single biggest hurdle in this whole exercise can be summed up in one word: retrofitting. If you read the first article in this series , you will be aware that this project is trying to add an RCA (also known as a Phono) Jack onto my JaF64 RF Modulator replacement for the Commodore 64. If you haven't read that article, then now you know. My problem is positioning that…
Well, here's a turn up for the books. I'm sure I'm not the only person who felt pretty darn certain that the RCA Phono Jack on the old Commodore 64 RF Modulator was a relic; past its time, and its usefulness consigned to bygone days. But then Reinhard Grafl (aka C0pperdragon) comes along with another amazing idea and my preconceptions about that jack are stomped into grey rubble on the floor. So,…
I gotta admit, I never thought this day would come. And yet here we are. The myth becomes reality. Our story begins on the 30th July 2023 with an announcement: "J-CIA is finally here! After a long wait, J-CIA is finally released! The released version ("J-CIA64") is only compatible with 6526/8521 - CIA. Amiga compatible version will be released later." This project was started in 2018 and a like…
Please note, since writing this article in April '23 the Ultimate II+ L has had several firmware updates which radically enhance the functionality of the device. I will write a new article to reflect these enhancements soon. Introduction My pi1541 was always a temporary stopgap. When I started getting into the Commodore 64 (after a 30 year hiatus) I really wanted an Ultimate II+ (developed by…
Unless you've been living under a rock for the past couple of years (or have zero interest) you have probably heard of the VIC-II Kawari, the brainchild of Randy Rossi, and, as the name implies, a modern replacement for the venerable VIC-II chip found in Commodore 64 computers. The VIC-II Kawari Mini (Rev 1.4) A few years have passed since the project got off the ground, and the global chip…
The Commodore 64, is many things, but a media centre is not one of them. That said, there is a mighty fanbase for "chiptunes", and if music generated by the SID chip in the C64 is your bag, then there are thousands of hours worth of music to enjoy. Video though, is a whole different ball game. There are pretty insurmountable hardware limitations that mean the C64 can never be a multi-media…
Not content with managing to design and have manufactured a perfectly respectable RF Modulator replacement for my SixtyClone 250466 Commodore 64, I had another itch to scratch. I keep thinking about my "all new" philosophy of these clone boards and whilst I have had to hit the second hand market for a keyboard, CIA chips, the 6510 CPU and the VIC-II there are much smarter enthusiasts than me…
If you've read my series on how I built my SixtyClone Commodore 64, you will know my first build was a disaster, due entirely to the appalling quality of the chip sockets I bought. I initially wrote off that first build, stripping out some components and binned it. Then, after a change of heart, brought it out of the garbage and vowed to resurrect it to use as a test bed for future experiments.…
I am stoked to advise, to those brave souls who manage to read this far, that Revision C of my JaF64 solved all my issues and that this Modulator Replacement now works exactly as planned, with all the correct component values. The odd behaviour I was experiencing with Revision B is gone. In the end I actually made a lot of changes: repositioning a bunch of components in the chroma circuit,…
If you've been following along then you will know that over the previous instalments I have taken you on the bumpy ride of designing and building a brand new RF Modulator replacement (The JAF64) for my 250466 SixtyClone board with no real clue what I'm doing, just to see if I could, and for the LOLs... though to be fair there has been far more cursing than LOLing. Here, in Phase 2, Part 3 and the…
Designing the PCB in KiCad In Phase 2, Part 1 , after much graft, I got the hang of designing my modulator replacement schematic in KiCad. Now I am ready to take all the parts I have specified in the schematic, and import them into KiCad's "PCB Editor" to begin to layout the actual printed circuit board (PCB) I want to have built. This is both daunting, and exciting. Daunting because, as with…
Building the Schematic in KiCad If you've been following along with this series of posts about trying to build an RF Modulator replacement from scratch, you'll know how I got to where I am now. There have been frustrations, confusion, misunderstandings, blind alleys and a memorial service for a Zener Diode. Ultimately though I achieved something approaching a staggering triumph. Some might call it…
Prototyping with a Breadboard Revision B Lets start, as always, with a recap. I had this zany idea to build my own RF Modulator replacement for my SixtyClone C64. In Part 1 I gave my reasons. In Part 2 I messed about with the original schematic to come up with my design. In Part 3 I tracked down my components and in Part 4 I built Revision A on a breadboard and failed to get it to work, blowing a…
Prototyping with a Breadboard Revision A In Part 3 of this lunacy, I sourced what I thought were suitable components for constructing a new RF Modulator replacement. It is entirely possible that certain elements I chose, especially the transistors, diodes and inductors are not suitable but if problems arise we can address them later. I'm also going to repeat my mantra about this not being a…