New Commodore 64 RF modulator replacement - better video, stereo support, and more
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- Опубліковано 4 лип 2024
- This episode is sponsored by PCBWay www.pcbway.com
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Build, install and demonstration of my C64 and 128 RF modulator replacement. This replacement provides a number of features like direct s-video and audio outputs, along with improving the video output of all 64s and 128s.
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🛠 Tools and kit: / tools-and-kit-77570017
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RF replacement comparison video: • Commodore 64 RF modula...
Longboard
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PCB: www.pcbway.com/project/sharep...
BoM: github.com/TheRetroChannel/C6...
GitHub: github.com/TheRetroChannel/C6...
Shortboard/128
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PCB: www.pcbway.com/project/sharep...
BoM: github.com/TheRetroChannel/C1...
GitHub: github.com/TheRetroChannel/C1...
Sven Petersen's C64 AV adaptor: github.com/svenpetersen1965/C...
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0:00 Intro
4:36 Build
16:06 Install
22:10 Standard features
24:30 Composite advanced features
26:47 S-Video advanced features
28:08 Chroma/Luma bypass
32:16 Mono/Stereo
34:31 Hard reset
37:56 Breadbin/64C and 128 examples
38:53 Sharing is caring
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Thanks for watching! - Ігри
I am really enjoying this project. 👍👍 Your PCB layout is crisp and clean, and the hard reset option is a great added touch! Now off to PCBWay I go...
I just ordered a 128 so we’ll see what it needs to be done!!!
Excellent work, exactly what I've been wanting to see for a long time. I will definitely be building at least one (for my C128 Neo), and probably more. Thanks so much for making this!
Amazing contribution !!!. Thank you so much for this. During my next holidays I'll make three for my 1xbreadbin + 2x"C models". You are amazing 🙂
Great work. Nice to have another replacement and this one looks well thought out with comparison to existing options.👍
Thanks for the community support in making this open source! I've ordered a few of the PCBs and will look forward to putting something on my own channel (Reviving Retro) once I receive them. I have a few systems using Copperdragon so this will be a nice change and rad channel topic. I'll integrate it into one of my C128 NTSC units since you mentioned their sparsity across the pond there!
So timely :) i was planning to do something like this with the second C64 I acquired. Great work as always!
Thank you very much for this video Mark! Very interesting. Cheers from Canada!
Nice job Mark. A very well thought rf modulator replacement packed with useful features. I'll definitely order a few and hope I'll find some spare time to build them.
These boards look great Mark! One of the first mods I did to my original C64 (when I got back into retro four years ago) was to build a modulator replacement PCB. I ended up using the TEBL modulator replacement as it had pins to do the chroma/luma bypass direct to the VIC-II. I agree that there does seem to be a noticeable image improvement keeping these signals away from others.
I think I'll add your boards to my next PCB order from my favourite vendor 🙂
Great project and presentation... I will do it for my long and short board Commodore 64s... Many thanks...
For follow up, I've built the replacement modulator for my C64C and I've connected it to my LCD TV/monitor via s-video cable.. The result is stunning, best view ever... Thanks again for the project...
Looks great! - Looking fwd to building a few of these.
still need to get some s-video connectors and the composite trimmer. in the Shortboard version, ran out of 501 (500 ohm) trimmers so I used a 201 trimmer for RV1 (200 ohm) instead. Should be ok as the fixed option is a 75 ohm R5. Only recommendation is to break out the stereo pads as jumpers for rev 1.1 🙂
Yeah 200 ohm should give you enough range to find the sweet spot. I only went with 500 there to keep the unique parts count down.
For the stereo and L/C bypass, I went with closed pads as it seemed safer than putting jumpers on there. If somebody just wants an RF replacement without the extras then they would need to remember to install jumpers on all those. And I figured if you have a stereo SID then you're not going back to mono anytime soon.
But thinking about it now, do other stereo SID solutions switch to mono when a non stereo track is playing? I only have the ARM2SID which does do that, but if others don't, then I can see why you'd want to have a jumper there. Thoughts?
Really well designed board.
I need one for my C64c.
Very cool! Thanks for sharing the board instead of charging $$ for it. Thanks for sharing
I really like this solution better than the Copperdragon Analog board because of all the other features you've added. Very nice work and excellent demonstration :-) The SX64Man was gracious enough to offer me a couple long board versions of the modulator replacement. Bravo !
Very nice. All I need now is a C64!
This is a great project. Thanks for making it. I ordered some C64 Shortboard version boards. My Commodore 128 video was awful, and swapped in your board, it is much better. I missed taking a before picture. It was so bad I really never though to use the 128, as my Commodore 64s both looked so much better. This board brings the quality at least to as good as the 64s. I haven't actively compared the 128 to the 64s with their RF Modules still installed. I was going to do the Chroma/Luma bypass, but the improvement without doing it is so good I didn't go to the trouble.
Nice, I just put one in a 128D the other day. I wanted to take some before and after pics, but after I installed it I realised the before pics didn't get saved. I didn't bother with the luma chroma bypass on this one either as it already looked much better. There's still some obvious jailbars on the 128 basic screen but nothing will completely remove those without sacrificing sharpness
@@TheRetroChannel , I can see the jailbars still too. They aren't awful though.
We owe you one: Nice build, Mark! 👍
Thank you guys!
Works fine with NTSC. You missed the 10K-11K load that the RF modulation puts on the Audio output. Without it, the audio output floats at about 2.5vdc. I added a 10K resistor from pin 4 to ground and audio output looks better and sounds better.
I just did some tests with an original RF modulator vs this one. There is a 2.5VDC offset at first power on with both, but that drops to zero once the audio out is connected to an amplifier/tv whatever.
Capturing 3 audio samples (original RF, my RF, and my RF with the 10k) in audacity and doing an ABX test, I cannot pick out one over the other. They all look and sound exactly the same to me, that's not to say there is no difference, just I cannot find it
Great Video , thanx
Really nice!
Mods on my breadbin C64 and Alps 1541 have gotten out of hand. I've drilled SO many holes in the poor things. Please don't hate me!
C64: (Originally found by my daughter in a closet full of kittens she rescued from a busted drug den while gutting the property. It was covered in - it was a mess. It did not work. It had a bad SID, corroded keyboard, bad RAM.
VICII2 NTSC / PAL switcher
Reset switch wired to 556 dual timer IC
SIDFX (yes, with the 6581R4 AR)
FU32 dual beam tetrode vacuum valve headphone pre-amp (Broken apart and rewired so it all fits inside case, vacuum tube sits on top case, inputs / outputs, power jacks remote wired with shielded coax, holes cut and RCA jacks, etc mounted.)
JiffyDOS
Red / Blue IRQ activity LED
Ray Carlsen power supply. Get one from the man while he yet lives
Mechboard 64. Early C64-C white keycaps with front print. Cherry MX blue switches.
Lighter color "Made in England" case
Orange VIC20 Function keycaps
Potentiometer for left and right channels volume control
Four potentiometers wired to paddle controller legs of joystick ports for Cynthcart 64
A little OLED audio spectrum analyzer for use mainly with Cynthcart 64
Heat sinks everywhere
I think I might build this mod now! - thanks!
1541: (Came from same place. It avoided repair. It had a bad read / write head and cat urine destroyed much traces and such inside. I wound up cleaning it in dishwasher and ultrasonic cleaner then sending it to a guy on eBay that repairs 1541's - it could still be used for parts, bought a good working unit from him.)
RAMBOard
Parallel port burst nibbler mod with 15 pin game port socket in side of case
Switch Mode Power Supply - makes lighter, cooler
Track Display
JiffyDOS
Reset switch
Device ID switches
My datasette got no mods, only a rebuild + clean and lube.
Great project!
PCBs and parts have been ordered to build several of each variant. I want to build one for my SixtyClone, the Shuriken I’m using is okay, but it looks like the image is better using yours.
It will be interesting trying it out on my Commodore 128 'daily driver' as well, the image has never been very good on that machine and can use all the help it can get!
Then because, ‘why not?’ I’ll try them out on various boards laying around my lab space for fun.
Thanks mate, the shuriken and the RFout from Edu Arana are the only ones I couldn't get my hands on to compare. I'll be interested to hear what you think of them once you get them installed
Would it improve the signal quality if you use a shielded cable like from an audio cable for the luma/chroma shortcut with the shielding connected to ground on one end?
It might, but you probably won't be able to see a difference if you keep them failry short. The more important thing would be using shielded cables to the display, especially with S-video
Hey Mark, love your work here! I'm curious on your choice of 2n2222 transistor compared to the BC547 and 549s used on other modulator replacement boards. Did you find the 2n2222 to provide a cleaner output? Or maybe was it just a matter of the pinout differences better matching your desired board layout? Thanks for designing these, I certainly plan on building a few!
Honestly, it's because I had heaps of 2n2222s and only a couple of BC547s. I did try it with 547s and it looks the same, so you could flip around BC547s if you prefer
thanks for sharing the PCB. Can you link to the red tool you use to adjust the legs on the resistors?
No can do, pretty sure that thing was made in the 80s and I've never seen them available anywhere. Your best bet would be to look up "lead forming tool" there are some similar ones out there which I think are still available. Otherwise there's a 3d printable one that looks similar to a ruler with a bunch of notches that tapers inwards towards one end
@@TheRetroChannel I looked for some lead bending tool and found some on aliexpress.
Question: Is you design optimized for PAL? If you look at modulator designs, the NTSC Chroma input uses coils and caps as input filters. Your PCB is almost part for part the same as the PAL modulator. I guess I will find out soon how well it works for NTSC.
It's not necessarily optimised for PAL, but most of the design was done using a PAL machine and then tested with NTSC to ensure compatibility. Yes most of the filtering has been removed to provide the sharpest possible image, the downside is any noise from the 64 also becomes more apparent
Really nice! Does it work with ntsc and pal? Thanks!
Yes, it's been tested with PAL and NTSC. The only thing I haven't been able to test it with is an NTSC 128 as they're impossible to find here in Aus, but it should work just fine
Excellent! 🤩 I'm late to the party, but you might have just made the best thing since sliced bread for UA-camrs or anyone else who wants to run S-Video to a capture device while simultaneously using the main video port for a monitor. I was actually going to hack an S-Video port onto my c0pperdragon modulator for this purpose, but now I think I'll just build this! ☺ The only thing I'm pondering from a design standpoint is that the C64 shortboard has ferrite beads cleaning the chroma & luma signals of high-frequency noise on their way to the main video port, but the signals going straight to the S-Video port on the modulator itself do not benefit from this. I'm considering if I could add beads, and where. Unfortunately I don't know how to edit a PCB, so I'd have to hack them in. The schematic suggests that I could put a bead for chroma in series with R1, but that for luma, I'd probably need to break a trace somewhere and solder a bead to the surface of the PCB to re-connect it... if I'm reading it correctly. (Anyone with thoughts, I'd welcome them.) Either way, I'm looking forward to NOT having to use splitters and other weirdness on my main video cable to do capture in the future, AND cleaning up some jailbars on my 128. Thank you! -- JC
Putting a ferrite bead in series with R1 should be fine. For luma, I guess you could put it in series with R7 (unless you plan on installing the trimpot instead). You would end up with 2 beads on luma at the DIN port but it should be fine.
Honestly I didn't bother with adding ferrites as I couldn't see a difference when I tested with them, but they wouldn't do any harm to add. Also keep in mind if you want to run two video outputs, you should stick to using 1 svideo and 1 composite. The board isn't designed to use both svideo outputs at the same time (although it may work)
@@TheRetroChannel Thank you very much for the advice and warning! I was in fact intending to simultaneously run L/C to my monitor and S-Video to my capture device; it would be so utterly convenient to just hit "record" whenever I wanted to capture, rather than fiddling with cables each time. If this configuration risks damage to the computer, I would respectfully suggest warning people away from it in the "Pre-Emptive FAQ" on GitHub -- but if the worst that can happen is degradation of video quality from splitting the signal, I'll give it a go anyhow and see what happens. Even if I have to keep switching my monitor back to composite while capturing, I'll still have a better experience, as the comparisons show your composite output looking MUCH better than the c0pperdragon that I'm presently using! ☺ -- JC
I saw in the video you installed the replacement unit on a the 250407-01 (A Board) with the 8 pin video, so my assumptions are it would also work fine with the 250425 (B Board) and 250441-01 (B-2 Board if you can find one out in the wild). Does it work with the "original" version 326298-01 (with the 5 Pin Video composite only Output)? Sure would be great to be able to get S-Video out of that puppy!!! All in all impressive and excellent work!!!
Yes, the longboard version works with all longboard revisions except the 326298. I may look at something for that in the future, but they're not easy to come by in Australia. I have one, and it's an NTSC unit, so maybe one day...
Building one of these myself. Parts all arrived today. Ahh...i totally didn't pay attention when ordering all my bits n pieces and ordered the C option for the S-Video connector instead of the E option....woops. Think I'm still good? It'll be going in a breadbin sixtyclone *466.
It'll match my purple mainboard nicely as i got it done in purple too from jlcpcb. (nothing against pcbway, i just prefer jlcpcb) :)
Thanks for sharing your work. :)
You should be able to use the other svideo connector, espcially as it's going in a breadbin case. The connector itself will likely be hard up against the case, the "E" option fits within the case cutout, whereas the "C" option will not. Just be sure to do a test fit with the board inside the case before soldering in the RF replacement
Your board seems to really improve the picture quality...very nice. I have tried Mr. Aranas RF Out board whiche gave me a terrible ghosting effect on every Monitor / TV set I have used. Does your board also improve the picture quality on CRT devices? Would be really nice if you could show the improvement on CRTs. Thank you for your infomative and entertaining content. 👍
Thanks, I've tested it with a number of CRTs with good results. I'll have to get some new before and after shots on a CRT, I did take some ages ago but can't find them now. I will say although it improves the image on a CRT, it's much harder to see the difference as a CRT will hide a lot of issues with the original RF modulators.
I'll add a pinned comment here when I have some new pics, might even add them to the GitHub page
Question, if is possible to install this on the board with pin connectors? or using them will raise the high and will not fit the case holes?
It might work. The board usually needs to be raised up a little to meet the holes, but I haven't heard of anyone trying it yet
@@TheRetroChannel Thanks. I will do a tests once I get all setup and let you know.
I have C64 video question to ask you, but not exactly related to your project.
I have a C64 Reloaded Mk2, and I’m using the 8 pin DIN Video out, to the VGA Upscaler device I bought on EBay.
The NTSC 6567R9 VIC2 sits on the LumaFix64 Combo, which removes the jailbars on the screen. The downside is, it’s a very sharp image with the annoying checkerboard dot pattern all across the screen.
It gives a bit of a CRT retro look, but it’s annoying after awhile with some eyestrain. I was thinking about trying another NTSC VIC2 chip, like the 6567R8, to see if that checkerboard pattern will go away. Do you have any thoughts or suggestions? The Reloaded Mk2 does have the 4 Pin mini S-Video connector, I haven’t tried this yet; but don’t want to spend a lot of money for a RetroTink if no improvement occurs.
I have tried the PAL 8565R2 with the LumaFix Combo, and the image is perfect! No jailbars, no annoying Crosshatch dot pattern across the screen; although the boot image does appear to look a little dark.
I just need some suggestions to get rid of the NTSC crosshatch dot pattern annoyance.
There's too many variables to say for sure. It could be the VIC-II producing a noisy output. It could be the upscaler doing a poor job with NTSC signals. It could be something on the mainboard coupling into the chroma signal around the NTSC frequency.
If your lumafix has a pot to adjust the chroma level I would try that first. Otherwise consider using a different upscaler with svideo input, you will always get a much better image from svideo than composite. And you can always use the upscaler with other computers and consoles that output svideo. Or stick with PAL, all the good stuff runs on PAL 😉
@@TheRetroChannel thank you for responding and the useful suggestions! Yes, the VGA Upscaler I bought from EBay was initially designed with PAL in mind; that’s why the PAL VIC2 chip display always looks so much better and clear. The seller can’t tell me why I’m seeing the dotted crosshatch pattern with the NTSC VIC2.
But yes, I am getting more tempted to buying a 4 pin S-Video cable and a RetroTink upscaler. I’m hoping the RetroTink will filter out that dotted pattern, with the LumaFix Combo.
By the way, I have tried all three pot adjustments on the LumaFix Combo, it only eliminates the jail bars. With the Chroma bypass jumper in place, it makes just the tiniest improvement with that crosshatch dotted pattern. I could try soldering a 350 Ohm resistor to the center pin of the Composite DIN connector going to the upscaler. See if that might do anything.
Yes, when a game or demo calls for a PAL VIC2 chip, I’m happy to oblige!
@ChrisCromwellHP A retrotink and svideo will certainly look sharper than composite, but it may also sharpen the checkerboarding. I guess you won't know until you try it.
The resistor mod will not help with composite, it is designed to bring down the chroma voltage level when using svideo.
Instead of doing external chroma/luma with two pads you cut and a pin header, just use two pin headers with jumpers on them. One side has the board inputs, the other goes to the buffers. To use external, you remove the jumpers and put wires from the VIC on the buffer side. This would also allow you to loop anything you want into the chroma/luma path. Should fit in the same amount of board space too.
Possibly. I think during the many revisions I put the pin headers on there first, and then realised they would still have a connection back into the mainboard on the RF side. So I squeezed the pads into the remaining space. Honestly it probably won't make a difference if the pads are left connected as the signals will have no reason to flow back into the mainboard
is not possible to have audio (mono) in the s-video output? and... why svideo and not rgb? maybe is not possible on the c64/128? thanks
Svideo has no provision for carrying audio. The VIC-II in the C64 does not generate an RGB signal, so svideo is the best you can get
Forgive the N00b question, but I have a bunch of C64 Breadbins, a C128, a 1702, 1084-D1, 1085 and a Philips Cm Mk2 monitor. Would this benefit me at all ? at 26:16 you I think you say it's not worth it (for composite)
I meant adding extra components on the board to gain a minor improvent with composite wasn't worth it. Have a look at the comparison video for what you can expect (link to it is in this video's description)
You should still get an improvement over the stock composite output, and also see an improvement with the luma chroma inputs on your Commodore monitors.
@@TheRetroChannel Thanks for the info as the output on my monitors isn't as good as I remember them back in the day ( a recap may help too)
@@TheRetroChannel Well, I've just looked at the other review and I've ordered them from PCB Way. Thanks for the vids
👍👍👍👍
I have 2 C64 machines, one Breadbin, and one C64C. Both running with Copperdragon analog RF replacement board. I got a pretty decent picture on the C64C, but not so great with the Breadbin (still much better than the original RF modulator) The Breadbin had a 6569R3 on it, so I thought the latest version (R5) might be better, bought one, and yes, it was much better but still not as good as the C64C. Being me, I bought a 8565R2 and modified the voltages on the board accordingly, and finally yes, a clear picture "almost" as good as C64C. That "almost" part have been bugging me to this day and when I saw the 100p - 200p thing on this video, I said "there it is!" for a brief period but then you said that the cap had nothing to do with the S-Video output. I have looked into buffering video signals with discrete transistors before and in fact that's how I did the composite video mod on my Sinclair Spectrum. It is a cheap and effective method. I will study the schematics (if you have them) on your Github and order a set of boards from PCBWAY to test them out. But on the contrary to your result in the previous video, I am quite happy with the Copperdragon board. This may be because I don't have anything else but the original RF modulator to compare it with, which is the main reason I want to test your design. A small note on the design, if you ever make a second revision, please do not make those solder jumpers preconnected with a trace in between, much easier to solder/desolder them than trying to cut the tiny trace in between without slipping and damaging other stuff. Great work, I appreciate you making it public big time. Maybe you may want to do another video on this where you explain the working of the circuit too. Thanks!
For me, the c0pperdragon replacement looked pretty good with s-video but not so great with composite. There's also a slightly modified version of the c0pperdragon board on PCBWay, and to be honest I couldn't see any difference between them in terms of video output.
As for the LC jumpers, it's funny as I did have them disconnected in a previous revision. The reason I connected them by default is I figured a lot of people won't use the LC bypass, and then if they didn't bridge them the board wouldn't work at all. But either way it's not ideal I guess.
The schematics are available on the GitHub page, and I will add the board design files shortly for anyone who wants to make their own changes
@@TheRetroChannel To be honest, I never tried the composite out of the Copperdragon, you may be right there. I won't have time to build it in near future but I will order boards, and study your schematics. I may come up with some questions if I see anything I don't understand. Please consider making a video on the working of the circuit, I know I would appreciate it big time. Thanks again!
I build one of this, exited about it. Image and color are great but I get gradient kind of movement on the image....(NTSC)
Are you using svideo or composite?
@@TheRetroChannel NSTC, S-VIDEO output , vic-ii kawari mini with DOT-Clock Mod. I put back the original modify modulator....no issues.....
Hmm ok. It's hard to know what the cause would be without seeing it. I'd suggest double checking all the components to make sure they are making good connection with the board (you could just push on them with your finger and see if anything changes on the screen). Otherwise it could be a faulty or wrong value component
@@TheRetroChannel So I verify my work, all values look ok . I recorded a video....I will try to send it to your email address....I build a second one and not luck....
Nice work bud. I love your designs and dedication. Will this solve the ghosting effect? 250407 I'm going to try to just change the 470uf capacitor in the modulator for now (so I've read) and damn man u have Gianna sisters working mint with your mod... that's a hard one:)
It should eliminate all ghosting, but no guarantees with this stuff right. I've seen the 470uF cap in the modulator leak in one or two cases, but even after replacing all caps in there I don't think the video quality improved dramatically, then again I didn't take before and after pictures so maybe it made no difference at all
@@TheRetroChannel hey thanks for replying. I have 2 other 407 c4s and I've never seen the ghosting.. until this one. Jw, what size tip did you use to remove the 3 bigger mounting pins for the rf? I also have a hakko and love it. Only have the standard one that came with it. It won't do for those pins. Sorry for running up comments.. but your thoughts are appreciated:)
Heh, the tip I was using also wouldn't work on those pins, it's a 1.3mm. There's a jump cut in the video at that point to cut out all the swearing. In the end I still used the Hakko to around the sides of the pins and solder braid to mop up the rest.
I have the 1.6mm on order and I think that's the biggest you can get for the Hakko.
@@TheRetroChannel ha ha 😂. That's funny, but agreed 👍
Absolutely awesome. An excellent example of shed design at work. How many compute units does this have?
5 PCBs are $5. 10 pcbs are also $5 - lol