Good work Todd, you have come a long way within a relatively short time, and I enjoyed watching you learn and become more confident with every repair. Along with your diagnosing skills, the quality of your videos has improved too. This channel has become one of my top 5 retro channels now. Glad to be here!
That's high praise coming from you, Bora. I appreciate it. You might want to wait for part 2 to see if I really deserve it. 🤣 Thanks for watching and for the compliment.
@@YARC-1981 Listen i think it would be great if you could give the interesting 326298 motheboard the tender, love and care it deserves, especially it is one of those early one's :)
@@Miidolf The plan is to try to get it populated and working, assuming I have enough spare parts left at the end. My biggest concern is VIC-II's. I only have one spare left at the moment.
@@YARC-1981 I would appreciate that, beyond that iam sure that you making video troubleshooting that board would make an interesting video too :) For the c64 purist getting the exact 1982 chips might be an real challenge, the ceramic vic-II for starters. Who knows that board might originally have had other ceramic chips too.
Sorry u had a bad vicii.. that freaking sucks. Last year I had 2 boards with bad viciis. Urg. But one.. a 425 as well had no signal... but it was the 8701. Thankfully.. I was hoping the same for you:) and the last board u worked on.... u have to admit.. that is very satisfying that the pla wasn't just the fault. Love it 😀
The good thing about the C64 is that all the expensive chips are replaceable with modern replacements. It would be nice if the Kawarii were a simple replacement and not an "enhanced" chip. Plus, they are not as readily available as a swinSID or PLA. MOSS gets a lot of crap for their chip fab, but without them, where would we be without the 6502?
I wouldn't go that far. I like the Kawari. I like the J-CIA. I don't like the prices. No disrespect to Jani or Randy. Additionally, many people have an issue with FPGA or CPLD emulation (not me, so don't ask me to explain their concerns). And I can't excuse MOS that easily, if for nothing else than the sheer number of SIDs that have died because of their mistake.
@@YARC-1981 Atari owners face similar challenges as the custom chips are going to become difficult to find. It's easier to get a Stereo Pokey with a SID on the side than to get a replacement Pokey for the Atari. The GTIA (Television Interface Adapter) is available with several enhancements but no direct replacements. I'd much rather that direct pin for pin, function for function replacements be developed before expensive enhanced chips. There is a semi-official source for original Atari chips but they are going to run out eventually if they haven't already. The smartest thing Tramiel did after buying Atari was to warehouse all the spares instead of landfilling them. All of his XE and XEGS machines were being built from free inventory.
I've got two OG 800's. Fortunately, all the custom ICs work. In fact, the only fault on either of them was a single bad 4116 DRAM. One was missing some keys (subsequently replaced) and I detonated a capacitor while recapping one of the power/av boards. That's all in other videos in the channel. If you're interested, you should look them up.
I humbly apologize for my mistake. Though 3M Scotch Tape and Sellotape are brand names, we use "scotch tape" here as a generic term for any transparent or translucent adhesive tape. I was (apparently mistakenly) under the impression that British people did the same with the brand Sellotape. I have no idea whether the tape on machine 2 was Scotch brand or not. Honestly, of all the things I did in the video, I didn't think what I called the tape was going to be the controversial one. Anyway, thank you for watching and for the comment. I really do appreciate it!
@@YARC-1981 The common form of scotch tape we have here is "invisible repair tape" and while some would still call it sellotape it is very different (and more expensive), any other sticky-back-plastic on a reel would probably be called sellotape here
So, not to belabor this, but it sounds like I wasn't actually too far off. I was using "scotch tape" in the generic to refer to a transparent or translucent adhesive tape and you use "sellotape" as a generic to refer to any other sticky-back-plastic on a reel, it sounds like our definitions aren't too far afield of each other.
On your 1st board repair there are MOS branded MUX logic IC's. Yes you have restored the board (...for now). But you know these MOS branded 74LSxxx logic IC's are very prone to failure (they normally don't die but struggle to achieve a logic High or Low (and timing issues?) so can cause intermittent/ seemingly crazy/random issues ), why not replace them now while on the bench instead of say after a month of use? As for the 2nd board, why didn't you temporarily populate it (after confirming it was safe to do so eg. Voltages, etc.) With the IC'S from your ZIF test unit. As I wouldn't Assume it was a 'Working Board' with the IC's pulled ... Would likely suspect the opposite, ie. due to a Board fault the IC's were raided to repair other systems (or Sold on eBay!). Oh! and when I was an electronics apprentice repairing C64's back in the 80's I was taught it was recommended that if a MUX IC failed it was recommended to replace both. Keep up the interesting video content!!!
Thank you for watching and for the comment. Your point is valid and I considered it, but the goal in the repairathon is to get the machines working, not to future-proof them. I can do that later. Plus, though these "jellybean" logic chips are readily available, my on-hand stock isn't unlimited, so if I want to make sure I have enough parts available through all 10 machines without having to wait for new stock to arrive, I have to use them judiciously. You'll see I did the same thing on machine 3, which still had two MOS logic ICs after I replaced the two address multiplexers. As for machine 2, I still plan to try to get back to that one at the end, assuming I have enough chips to populate it. I may take your advice and use the ZIF ICs in the case that I don't have everything left in spares. Thanks again and I'm glad you're finding it interesting!
I ordered the PCBs from PCBWay (www.pcbway.com/project/shareproject/Commodore_64_RCA_Video_adapter.html). The problem is sourcing the parts on the BOM. Some of them aren't available at the links provided and are now hard to find.
Good work Todd, you have come a long way within a relatively short time, and I enjoyed watching you learn and become more confident with every repair. Along with your diagnosing skills, the quality of your videos has improved too. This channel has become one of my top 5 retro channels now. Glad to be here!
That's high praise coming from you, Bora. I appreciate it. You might want to wait for part 2 to see if I really deserve it. 🤣 Thanks for watching and for the compliment.
Glad to see you working with c64's again :)
I'm having fun. Thanks for watching!
@@YARC-1981 Listen i think it would be great if you could give the interesting 326298 motheboard the tender, love and care it deserves, especially it is one of those early one's :)
@@Miidolf The plan is to try to get it populated and working, assuming I have enough spare parts left at the end. My biggest concern is VIC-II's. I only have one spare left at the moment.
@@YARC-1981 I would appreciate that, beyond that iam sure that you making video troubleshooting that board would make an interesting video too :) For the c64 purist getting the exact 1982 chips might be an real challenge, the ceramic vic-II for starters. Who knows that board might originally have had other ceramic chips too.
Nice work Todd:) can never get enough repairathons
Thanks, Donald. I appreciate that.
Sorry u had a bad vicii.. that freaking sucks. Last year I had 2 boards with bad viciis. Urg. But one.. a 425 as well had no signal... but it was the 8701. Thankfully.. I was hoping the same for you:) and the last board u worked on.... u have to admit.. that is very satisfying that the pla wasn't just the fault. Love it 😀
@@donaldblakley6796 You're foreshadowing part 2. I'll say no more. 🤫
Excellent video and work. Thanks for sharing
You're too kind, sir. Thanks for watching!
Never any shortage of broken C64s.
No. Commodore's MOS chip fab made sure of that.
The good thing about the C64 is that all the expensive chips are replaceable with modern replacements. It would be nice if the Kawarii were a simple replacement and not an "enhanced" chip. Plus, they are not as readily available as a swinSID or PLA. MOSS gets a lot of crap for their chip fab, but without them, where would we be without the 6502?
I wouldn't go that far. I like the Kawari. I like the J-CIA. I don't like the prices. No disrespect to Jani or Randy. Additionally, many people have an issue with FPGA or CPLD emulation (not me, so don't ask me to explain their concerns). And I can't excuse MOS that easily, if for nothing else than the sheer number of SIDs that have died because of their mistake.
@@YARC-1981 Atari owners face similar challenges as the custom chips are going to become difficult to find. It's easier to get a Stereo Pokey with a SID on the side than to get a replacement Pokey for the Atari. The GTIA (Television Interface Adapter) is available with several enhancements but no direct replacements.
I'd much rather that direct pin for pin, function for function replacements be developed before expensive enhanced chips. There is a semi-official source for original Atari chips but they are going to run out eventually if they haven't already. The smartest thing Tramiel did after buying Atari was to warehouse all the spares instead of landfilling them. All of his XE and XEGS machines were being built from free inventory.
I've got two OG 800's. Fortunately, all the custom ICs work. In fact, the only fault on either of them was a single bad 4116 DRAM. One was missing some keys (subsequently replaced) and I detonated a capacitor while recapping one of the power/av boards. That's all in other videos in the channel. If you're interested, you should look them up.
Scotch tape and sellotape are *not* the same thing - and yes we have scotch tape here :D
I humbly apologize for my mistake. Though 3M Scotch Tape and Sellotape are brand names, we use "scotch tape" here as a generic term for any transparent or translucent adhesive tape. I was (apparently mistakenly) under the impression that British people did the same with the brand Sellotape. I have no idea whether the tape on machine 2 was Scotch brand or not. Honestly, of all the things I did in the video, I didn't think what I called the tape was going to be the controversial one. Anyway, thank you for watching and for the comment. I really do appreciate it!
@@YARC-1981 The common form of scotch tape we have here is "invisible repair tape" and while some would still call it sellotape it is very different (and more expensive), any other sticky-back-plastic on a reel would probably be called sellotape here
So, not to belabor this, but it sounds like I wasn't actually too far off. I was using "scotch tape" in the generic to refer to a transparent or translucent adhesive tape and you use "sellotape" as a generic to refer to any other sticky-back-plastic on a reel, it sounds like our definitions aren't too far afield of each other.
Commodores are like a box of chocolates. You never know what you're going to get.
Too true. I've repaired a bunch and no two are ever the same.
On your 1st board repair there are MOS branded MUX logic IC's. Yes you have restored the board (...for now). But you know these MOS branded 74LSxxx logic IC's are very prone to failure (they normally don't die but struggle to achieve a logic High or Low (and timing issues?) so can cause intermittent/ seemingly crazy/random issues ), why not replace them now while on the bench instead of say after a month of use?
As for the 2nd board, why didn't you temporarily populate it (after confirming it was safe to do so eg. Voltages, etc.) With the IC'S from your ZIF test unit. As I wouldn't Assume it was a 'Working Board' with the IC's pulled ...
Would likely suspect the opposite, ie. due to a Board fault the IC's were raided to repair other systems (or Sold on eBay!).
Oh! and when I was an electronics apprentice repairing C64's back in the 80's I was taught it was recommended that if a MUX IC failed it was recommended to replace both.
Keep up the interesting video content!!!
Thank you for watching and for the comment.
Your point is valid and I considered it, but the goal in the repairathon is to get the machines working, not to future-proof them. I can do that later. Plus, though these "jellybean" logic chips are readily available, my on-hand stock isn't unlimited, so if I want to make sure I have enough parts available through all 10 machines without having to wait for new stock to arrive, I have to use them judiciously. You'll see I did the same thing on machine 3, which still had two MOS logic ICs after I replaced the two address multiplexers.
As for machine 2, I still plan to try to get back to that one at the end, assuming I have enough chips to populate it. I may take your advice and use the ZIF ICs in the case that I don't have everything left in spares.
Thanks again and I'm glad you're finding it interesting!
Thanks for the vid. What’s your video DIN to AV board? I could use one of those (or better, 1/8” phono instead of RCA).
I ordered the PCBs from PCBWay (www.pcbway.com/project/shareproject/Commodore_64_RCA_Video_adapter.html). The problem is sourcing the parts on the BOM. Some of them aren't available at the links provided and are now hard to find.
Where do you order VIC-II's from?
ebay. 😒
@@YARC-1981 I can see this is not a solution that fills you with joy.
@@michaelstoliker971 no. They're expensive and rare