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Nope. Was just thinking about this yesterday. I wish I knew more about how to triage this, and sounded like Osgeld was pretty busy with other things so I didn't want to bother him. Was kinda waiting for some other advice ot someone else who has the time to work on this. Was thinking of maybe sending to ITC. My luck it's a bad TIA and just needs a donor chip.

Nice! If I could afford it right now I would have jumped on it. Amazing package here for a wonderful console I have much affinity for.

Necro-bumping this for a quick update. I finally had some time to work on this today (as well as replacing the batteries on my three Dreamcasts with battery holders, yay!). I replaced the capacitor in C211 with this one to spec from Digikey. Good news and bad news: The bad news first - still no color. When I power on the system, however I see a flicker of colored artifacts/lines on the side of the screen. I don't know if that's signal noise or an indicator of the issue. Everything else works great though - loads games fine, sound is great, and the composite mod Osgeld used is fantastic, as the picture is clear and there is no ghosting I've seen with other composite mods. The good news, is that I ruled out C211 as the culprit. And as I'm a beginner at soldering, I'm kinda proud I was able to swap them out and not cause any other issue. That I didn't introduce another problem is a win in my book lol.

I just wanted to bump this because ITC recently posted a video on controller calibration using a loopback board and an alternative method for those who do not have a loopback board. QQ - are these loopback boards available today? Or are they old Atari service equipment that have since gone scarce?

Bumping this for a quick question. C211 is listed on the 2600 field service guide as a 22pF capacitor. If I were to replace this, will any 22pF capacitor do? Or is there a specific type I should be looking for?

I was tempted to get this, but it would just be a backup to my current CIB one (humble brag lol). The Trak-Ball is one of my favorite (if not THE favorite) console peripherals across ALL consoles - just playing Missile Command with it is transcendental. This one looked to be in fantastic shape, so congrats to whomever purchased it!

Hey not a problem and glad you are feeling better. Like I had mentioned in the previous thread, not looking for any sort of "warranty" so don't feel obligated, especially if you are busy with other things. I posted around other console repair forums/discords and I'm going to try to see if that solder joint on C211 is cold by resoldering it. If that doesn't do the trick, I'll let you know. Thanks for offering though! And if I do end up sending it to you, I'm paying you for the repair as I would any other modder, even for the diagnosis. If the TIA does need to be replaced, I have no problem getting a new modded console.

I've heard @Cmherndon79 does great mod work, so tagging him here. Does he also accept repair work like this? If I need to pay $80 for a scope to diagnose the problem, I might as well just pay that to someone who already has one and can repair it for me. BTW, other option is to buy one of their pre-modded consoles (it's ony $30 difference), but figured having a partially-functional console already would be the cheaper option.

Which is the voltage regulator? I think Best still sells TIA chips - that was my first inclination, to replace that. Since it's socketed it should be easy to pop in a new one.

I was able to use Paddles on it before, yes, so maybe just your console?

Hi Everyone: I previously posted in this thread, but it was suggested we break this out to its own thread for folks with similar hardware and issues to reference going forward. Back in April 2017 I purchased an NTSC composite-modded Woody 4-switch CX2600A from @Osgeld. It had been working great but was in storage for the past year unused (climate-controlled, dry finished basement in closed Rubbermaid storage container). I recently pulled it out after purchasing a Harmony cart for it, and when I hooked it back up it was not displaying color, only black and white. The black and white switch still works, as evidenced when playing Adventure and switching it I can see the grayscale changing. Here's a picture of the composite mod, which Osgeld mentioned in the previous thread: In the other thread, it was suggested I clean out and adjust the R213 pot which affects color. I used some electrical contact cleaner and adjusted it back and forth to free up any corrosion, but it did not fix the issue. I know it's getting voltage as I measured it, which I'll reference below. I also noted I can see some convergence going on when adjusting it either way, so it seems to be working as intended. The good folks in the previous thread asked me to take some voltage measurements of the areas of the board responsible for the color signal, which I've copied here: R213 - 6.22 R212 left side - 9.52 R212 right side - 6.23 TIA pins 9 and 20 - 5.02 TIA pin 10 - 4.66 I put in Asteroids, and yes voltage on pin 9 changed to 2.75. Turning the pot clockwise about a quarter turn increases voltage slightly to 2.82. Counter clockwise a half turn and it goes down to 1.81. For Pin 10, turning the pot clockwise about a quarter turn increases to 5.95. Counter clockwise a half turn and it goes down to 0.35. I was also asked to measure the voltage along the traces for multiple resistors. For orientation, please reference the picture below: ^ Top; v Bottom C210 "bottom" - 4.78 C210 "top" - 5.02 R210 "bottom" - 4.98 R210 "top" - 5.01 C211 "bottom" - 0.19 <- I wonder if this could be the problem? C211 "top" - 4.98 R222 "bottom" - 0.19 R222 "top" - 0.00 C215 "bottom" - 0.19 C215 "top" - 0.00 Upon close inspection, C211 doesn't look to be a stock resistor (maybe part of the mod performed?) and might suffer from a cold solder joint as referenced by a poster in the other thread: Or maybe those voltage readings are completely normal...I dunno. Here are some other pictures of the circuit board and mod for reference: The good folks @ChildOfCv, @DrVenkman, @fdr4prez and @-^CrossBow^- helped me get to where I am now, but I need some help to further diagnose this issue and identify a fix. Also, as I mentioned, this will be a good reference in the future for others with this mod setup. TIA!

That's great - given that color is mixed like normal, do any of the measurements I took earlier in the thread make you think of anything that might be happening? Is that low voltage coming out of C211 in particular worth noting? That's a weird looking resistor too (if that's even what it is) - I take it that's not stock?

Thanks again for your work on this! I placed my order on Sunday but never got emailed an order confirmation. I do have an order number and downloaded the invoice, but wanted to see if anyone else had the same issue.

Okay, thanks for your help nonetheless. I know I bought it from @Osgeld, I checked it was back in April 2017. I tagged Osgeld here - not looking for any warranty lol, but rather if he has any info on the mod performed which he might be able to shed light on what I'm experiencing with the color loss. I don't know if I have enough skill to replace the mod board with another, especially if the two mods are not compatible. But hopefully it's just an easy fix once I can figure out what's going on with it.

R222 "bottom" - 0.19 R222 "top" - 0.00 I measured the next one over as well, I don't know if that has anything to do with it. C215 "bottom" - 0.19 C215 "top" - 0.00

Yeah, I'd have to remove the glue to check, but I'll let you folks make the informed guess on whether this is a potential problem point or not, based on the voltage measurement above. And here's a closeup of the joint in question from the topside of the board.

First, I just wanted to thank everyone for being so helpful (and patient) with me as I triage this issue. As I stated before, I'm a newbie when it comes to EE so all this is new to me, but I'm excited to learn how to maintain my old electronics. Second, apologies to the OP for this thread, as I kinda hijacked it. Hopefully they don't care I made this into a sticky for general composite mod issues. Okay, first the orientation of my circuit board, so when I say "bottom" or "top" for my measurements this is what I'm referring to. ^ - Top v - Bottom C210 "bottom" - 4.78 C210 "top" - 5.02 R210 "bottom" - 4.98 R210 "top" - 5.01 C211 "bottom" - 0.19 <- I wonder if this could be the problem? C211 "top" - 4.98 If I look closely, it doesn't look like there's a solid solder joint on the bottom of topside C211 (see above). If I turn the board to the underside, that's exactly where the epoxy is in this picture below: I'll be pissed if that's what I have to replace, because that looks like a major pain....

Pin 10 is 4.66 I put in Asteroids, and yes voltage on pin 9 changed to 2.75. Turning the pot clockwise about a quarter turn increases voltage slightly to 2.82. Counter clockwise a half turn and it goes down to 1.81. For Pin 10, turning the pot clockwise about a quarter turn increases to 5.95. Counter clockwise a half turn and it goes down to 0.35. So it looks as if the pot on R213 does have an affect on the voltage of those pins. I also plugged it into the TV while it was open and it does look like there's some convergence going on when turning it, so it appears to be doing its job. And before anyone asks, switching the BW/Color switch does appear to change the grayscale so that's working as well. I even tried it on the input on my VCR, same thing. No color. But picture and sound come through fine. Weird that it had been working when I last used it about a year ago.

Well, that would make a difference wouldn't it... R213 - 6.22 R212 left side - 9.52 R212 right side - 6.23 TIA pins 9 and 20 - 5.02

Set at 20, I'm getting 0.03 for both R212 and R213, 0.00 on the TIA pins 9 and 20.

Both sides consistent, although I don't think this is 9V... I didn't bother to remove the shield again, so I just placed the ground on the exposed silver part of the circuit board. I don't think that makes difference, does it?

Okay, hope I did this right. So for the pot, it measured .52 as in the first picture. For pin 9, initially it measured 1.3 but as I was rechecking the voltage to make sure I had the right reading, it would steadily decline. That last pic was of .8 was the last measurement I took of that pin. For pin 20, it read the same as pin 9. Thoughts? Or did I measure it wrong? EDIT: keep in mind I changed the knob setting on the multimeter between the pot and the TIA measurements. In further research it almost seems like the TIA is dying. That pot is 5V if I read that correctly?

You know, I never put two and two together, but I've been following you on Ebay for years, for your Dark Tower repairs. I've got a complete boxed Dark Tower that thankfully still works but I saved your listings just in case I needed to get it repaired. Now I know you are the same! I'd collected a few Microvisions over the years for the other LCD screen in production. I may have to send you a couple of those just for that LCD backlight version. Thanks for all you do!

Hmmm... so I found the color wheel and sprayed it with some contact cleaner, then moved it around. Admittedly it was a bit stiff, probably due to age, but I got it moving nice and smooth after that. I also sprayed the switches just in case the B/W switch was stuck. Hooked it back up and...still the same prob. I took some pictures of the mod board, the AV connections and even the color wheel. Then I took a look at the underside of where the mod board is wired up to. I also took off the shield to see if I could find the trace from TIA pin 9 to the resistor, and I took some pictures of all of this. I don't know what I need to do with a multimeter to test that trace though.

Thanks! Will give this a try! Also love your videos and your service keeping these old consoles alive!