How To DIY Commodore 64 AV Cable

Inside the Commodore 64, the VIC-II creates the chrominance signal in a way that is impossible to convert it back to any form of RGB. The solution to get RGB out of this information is to listen in to 22 pins of the VIC-II to determine what signals it intends to generate. This is done with a smallish Altera FPGA connected to the VIC-II through a ribbon cable. On the FPGA, the luminescence and all the color information is generated, then converted into true YPbPr. For the complete mod, the RF modulator is removed, and the original A/V jack is still functional. This is effectively a very in-depth mod that rids the C64 of the TV connector and channel selector (that no one uses anymore) and replaces it with a professional-grade video output.

Each Galaksija Kit includes a power adapter, an AV cable, and all the parts you need to get up and running. This Kit does require assembly and soldering, there are no pre-populated parts.

Ok. Maybe that was a melodramatic and totally false account of the process. Had I simply paid attention to the few technical books and blog posts I had read regarding making my own S-Video cable, I wouldn't have been so challenged getting a clean signal to my LCD display. The issue I was facing was that there was way too much noise in the signal. Text was almost unreadable and the picture, overall, was just plain annoying to look at. So, I figured, if I had misinterpreted something along the way, surely, at least one other person could have done the same thing.

Once it dawned on me to try pin 6, Chroma, I went to work on a custom connector. I started by heating up individual pins of a 5-pin connector and pulling them out of the black plastic housing. I only needed three pins for testing: Luminance (pin1), Chroma (pin6) & Gnd (pin2). I had them sticking gently into the proper pins of the 8-pin port, connected the S-Video connector on the other end of the cable to the S-Video-> VGA converter and turned on the C64. The result? Perfection. Aside from the vertical lines I've read can't be dealt with, all of the jpg-like artifacts were magically gone. It looked pretty close to the Vice C64 emulator. I was ecstatic, to say the least!

I instantly logged into commodoreserver.com's chat so I could tell someone who would understand and appreciate that I figured out my video issue. While explaining it to AgentFriday (who so nicely congratulated me on overcoming my stupidity) I started talking about how I pulled the pins from a 5-pin connector etc.. that the Commodore 8-pin din was the 262° version, unlike the more commonly found 270° version... and then it dawned on me that maybe the only difference between the two connectors might happen to be the position of pins 7 & 8, which aren't used anyway. So I grabbed my 8-pin connector that didn't fit, heated up pins 7 & 8 with my soldering iron, pulled 'em out and the connector fit perfectly into the A/V port!! I now had a clean way of accessing pin 6, Chroma, from the A/V port and didn't have to wait for a specially ordered connector in the mail.

Hi, thanks for this post! I was looking for a while for a nice, clean and well illustrated post on building these for my Commodore 128.One question though, I read and understood the reason for the 300 ohm resistor, however, I have read on a similar page on video cable construction (which now I can't find grrrr..) that another thing that introduces noise is the "Audio In" pin, and the author solved it (improving the signal) by simply connecting this pin to I *think* it was the GND pin. Have you seen/heard of such a thing? I trying to find the page again to be 100% sure what pin it was connected to, since I only want to do this once and right :)Cheers!

Hello to all. RandyInLA, can I ask You to help me? sorry for my English. I have complete the S-Video cable for c64 and in my lcd Samsung with input S-Video the look is great. the trouble is when I connect s-video of c64 in video converter-to-vga. screen appearance is horrible, is full of noise, we say that is just disgusting. surely the problem is in the video converter, any suggestions? in vga converter goes wrong with either the samsung lcd tv that of a CRT monitor philips, identical noise. sin, connected directly to the LCD TV into s-video is perfect. helpHello and thanks

My Commodore is not the same pin outputs. Form your diagram mine is a little different. Here's what I could test so far on my Commodore 64C. Both black and white for composite and S-video.1. Right2. Ground3. Left4. U/N5. Video B/W6. U/N7. U/N8. Video? Is using red right channel and when grounded I get color. Using composite video cable. And no right channel.When I bought a S-video cable I still got black and white but now it's in stereo.

@e5frog Re: "It surprises me that a 5pin s-video connection wouldn't improve anything, must be related to the screen used."The article above points out that the C64 has different A/V ports depending on the year of the C64. For the ones that have chroma & luminance pre-combined onto one pin, and also the fact that the signals don't match today's standard S-Video levels, explains why the resulting S-Video signal via special cable can look bad. It worked on Commodore monitors, which is why people refer to that as Commodore Video and not S-Video. Only the C64s with the 8-pin A/V port provide separate chroma & luminance signals. Again, the article kinda goes into depth on this.

I made my own CBM video to S-Video cable yeeeeaaars ago. It did not include a resistor, nor did I perform an audio interference fix. It was just straight wiring of the proper pin signals. It worked fine on the CRT-based TV I used it for back then (a Sony XBR I believe). I am revisiting my C64 after a long time to do some more floppy-disk-to-file archiving and I currently it have it connected to my Sharp 37" LC-37D90U LCD TV via S-Video input. The image does not look right, probably for the reasons you described in this blog. It is kinda hard to describe. I am seeing an image but there is this rapid vertical "shaking" going on. It has the result of making the image look fuzzier than it should be. It almost resembles a video signal in need of "time base correction". I suspect if I connected a cable assembled per your instructions, I could achieve better results. I do have the 8-pin version of the C64, by the way. Question-- can you point to an online source for the parts you have used? I

@RandyInLA Like you, I didn't realize the character limit for posts. My original message got cut off right where I mentioned Mouser as someone I have shopped at before but I did not find DIN connectors there.I was hoping I could be pointed directly to the items you used, but I will just have to use your excellent photos as my guide. I wonder if this guy is building a cable to similar specifications: =61067Too pricey for me though.

Sigh. No go for my newly built cable. Not getting a video signal at all. I confirmed continuity on all connections. I did the extra step of adding the Audio In connection to ground also as described here: Once thing I did not consider when picking up my 300 ohm resistors is what wattage. I was asked this question at the local electronics store and I was caught off-guard as it was not mentioned on the above link or on this page. I just went with the one I thought matched the scale in the photographs. I believe it was a 1/4 or 1/2 watt. I am guessing that value is not critical for this project given the low voltages but I wasn't going to go with the fatter one I was initially offered.At any rate, I am not getting a signal. Perhaps I need to be connecting it to a true computer display device (and maybe an s-video to VGA converter while I am at it) and not the HDTV I am trying to use it with. Just to be sure it wasn't the on

Yeah, my goof. I switched the Luma & Chroma pins because I missed the line about the correct orientation. :) Working fine now, but sadly, did not solve my problem with the Sharp LCD. I think it is just some quirk with the TV. The cable also works with my home theater AVR and 4K TV. I am going to get some better quality DINs and redo the connections, however. It got a little messy in there after the fix I just did.

I already have VICE installed on my Fedora Linux system, and it works perfectly. But I would like to be able to transfer the about 500 original Commodore 64 disks I have to the system. I went out and bought a 1541-to-serial adapter cable online, but only after I had completed my order did I realise my system doesn't have old-style serial ports. Direct 1541-to-USB adapter cables are still in hobbyist prototype stages, but are there serial-to-USB adapter cables available for sale? JIP | Talk 17:21, 23 September 2009 (UTC)Reply[reply] 2b1af7f3a8