WicoKid

It behaves like an Odyssey 2....no different startup screens or graphic changes. After removing the bottom, it appears similar to the other Odyssey 2...with that said, it is adequately shielded. Eventually will recap and maybe a composite mod but since the keyboard ribbon cable lamination is already separated, didn't want to start mutiple disassembles but will post when I do.

Sure..I thought it was just an early model...maybe they just used available components. I had been kind of wondering about the stickers and serial numbers though. No other systems were mentioned.

I had been on the outlook for "The Voice" module recently and found a listing locally, so just went for the whole lot. In the included cartridges are the three in the picture, "Attack of the Timelord!" prototype, "Freedom Fighters" Advance copy/prototype and "Killer Bees" prototype. The labels on the "Killer Bees" cartridge and the "Attack of the Timelords" cartridge have the word "Prototype" as part of the printed label, ie not a stamp. I am in east Tennessee where Magnavox was headquartered in the 1980's (Knoxville and Greenville). The box is little rough, but a nice complete, I think, "The Quest for the Rings" game. Anyway, kinda neat.....Oh yeah, the guy I bought them from said a friend of his found it all in a storage unit. I

.....really odd.....maybe 2 errors.....when I bypassed the board circuitry from RIOT 23 to PIN 9, it still auto-selected until I removed and cleaned the switch and it was working. SO, I thought the switch was the problem and removed the bypass. It started auto selecting again; so put the bypass back in. It plays many games fine; residing in its chess piece box at present. The original power supply is still here but reads at just over 15 volts, so I haven't been using it. Any thoughts there? So far have just used another power supply.

Well....just do it...I removed the Select switch and disassembled; cleaned, reassembled.....it is working. Still confused with the multimeter demonstrating the switch was working and several times, with the switch not even in the loop, the Atari did the auto-sleect thing. I did reflow J101 while cleaning the switch as well. Thank you for responding.Will return here if recurs.

RESOLUTION:It appears the problem was on the mainboard somewhere between J202 pin 9 and PIN 23 of the RIOT. I am guessing the socket....maybe it warmed up just enough for a voltage leak somewhere, not to ground, but enough to trigger the select. I ended up just lifting (straightening out) PIN 23 of the RIOT so it didn't go into the socket and the behavior stopped. A "professional" next step may have been to replace the socket but instead I just bypassed all together and moved capacitor 226 to the switchboard and ran a wire from straightened out PIN23 to PIN 9 on the switchboard. LOL...nevermind....jst didn't wait long enough....even with the lifted pin and bypass as above , after, I'd guess, 15-30 minutes of Ms. Pacman running, it started cycling game select again.

Is it possible for the pin 23 0n the riot chip to be more sensitive than my voltmeter? its literally switch up no continuity, switch depressed, continuity. Along those lines, I just unplugged PIN 9 of J1 (goes switch to PIN 23 of RIOT directly) and same behavior.....the only other possibility of grounding was cap 226, so it just cut one of the legs.....same behavior as if the select switch is closed, but there is NO continuity between PIN 23 and ground. Logic probe.....yes....if I let the Atari sit for a few minutes and turn on with logic probe on PIN 23 of riot no sound then after several seconds DOES go low and flips through selects........should be then RIOT chip, but if I take apart one another 2600 it would make the 4th chip in that slot with the same error......can't imagine how it is getting near ground

I have a heavy mixer, initially nonworking but slowly getting it back. It took a while, but once I found a shorted inductor (L101) I thought I was done and put in a simple AV composite mod which seems to work fine. However, Behavior: On Combat after resting the console for 5 minutes or so, I can play for 20-40 seconds then but after it suddenly stops the game and cycles through game selections. It has same behavior on other cartridges but can play Pitfall without problems. Have tested Select switch repeatedly and it works ; it just grounds pin 23 on the riot chip. Have confirmed continuity between switchboard pin 9 and pin 23 on RIOT repeatedly. Since the only route to ground PIN 23 is through ceramic cap 226, I replaced it and get the same behavior. I have changed out the RIOT and TIA and CPU and get the same behavior. If the 2600 is on and already malfunctioning (that is spontaneously cycling through game sections) pin 23 on the RIOT is not grounded but if I press the game select switch is does ground AND the game select will override the automatic cycling (that is it selects, goes through the game selection in rhythm with pressing the switch). If I hold down reset switch, the tanks will rumble but when I let go, it immediately goes back to cycling through game select. Looking at schematics, it initially seems that the circuit Select switch to PIN 23 of RIOT is the only possible source. When I look at the 2600 service manual, it checks out and suggests I change RIOT, CPU, TIA; which I have. I found a thread from 2010 "What does the Game Select switch actually do?" which has this statement "The primary difference between Port A and the Port B is in the operation of the output buffers which drive these pins. The Port B output buffers are push-pull devices which are capable of sourcing 3 ma at 1.5V. This allows these pins to directly drive transistor switches. To assure that the microprocessor will read proper data on a "Read Port B" operation, logic in the R6532 allows the microprocessor to read the Output Register instead of reading the peripheral pin as on Port A." Aside from looking a schematics, I am well out of my league here. Is there some command coming from the CPU that is making the Select cycle that does not require the hardwired "ground requirement" that the Select switch mechanically provides? If the CPU works, what other associated circuit should I look at to find the error. I do note that if I turn off the machine and leave for 5 minutes, I can play the game for 20-40 seconds before it starts cycling, if I turn it off then immediately try to play, it just starts up cycling through. Appreciate any feedback.

......the board worked worked initially with new processor, normal voltages, then soon began the same behavior....I think there is a voltage leak/short n the board or in a component I cannot find....definitely not worth going through chips....this one headed to parts pile

Looking back tried a lot of different things including, after seeing the power output from the regulator was low, tried 2 different regulators. Also inconsistently, a couple of times, there was a remarkably brief, very faint beep on my voltometer when measuring between 5v and ground on the regulator; so faint and then resolved I wasn't sure if I was hearing things. Several steps later....after mixing and matching parts, I arrived with a combination that worked. In course of finding the working combination, on the motherboard i was planing to use, the video went completely out and there was only a low grade hum, then I found low voltage in and out on the regulator, then identified a short between the 5 V and ground on the regulator that went away when the switch board assembly was unplugged. On the motherboard, there was a short between 5 volts and ground. After changing a ceramic capacitor it persisted, so starting unplugging chips and short went away on removal of 6507 processor. The processor had a short between pin 2 and 4 (5v and ground)....right now waiting for a new 6507 vs taking some more time (and risk) of disassembling the working machine. So over time believe it was the course of a failing processor; but will update when I put in a working processor. I also wonder about the power flow or sync on the composite mod (linked in above post) as the video still flickered at times , so I replaced the composite mod with a single transistor design.

I found what I thought was a non working heavy sixer, but is has board REV B ,with the same switch board and motherboard assemblies as a light sixer I have. After some work on the one I just picked up (Console5 cap kit) and building a composite mod (https://oshwlab.com/Djoulz/atari2600-composite-mod) it starts and works with a great picture and sound for about 30 to 90 seconds, then the picture flickers, becomes video noise, eventually goes primarily blank (CRT cannot detect video signal) then a rare video noise; throughout all of this the game makes the correct sounds. Initially I focused on the caps and chips on the motherboard switching out parts with the working board but found that I had the same behavior. Eventually I found that one of the switch board assemblies makes both motherboards work fine, the other produces same abnormal behavior as above. On the nonworking Switch board, I have changed all capacitors and the regulator....the only thing left are the switches and the 2 postage stamp sized inducers (both are 15 uH). I don't have any 15 uH inducers but since they are the same sized, I switched positions and behavior was the same. Which electronic component on the switch board should I suspect? If it is off for several hours, it works for about 60-90 seconds before flicker and fade, if I come back within in few minutes, its blank....if I let it rest for 15 minutes, it works for about 10 seconds then flickers and goes out.

So, on a Colecovision just seeing if there are chips I can avoid testing: It wil boot Atari 2600 games, color not right though, like Pitfall sky is purplish. The switches/buttons on expansion work forAtari games, demo modes will start and run but NO response to joystick or joystick buttons. If I reset Ms PacMan on expansion 1, the game starts, Ms PacMan goes left to wall and sound works.I don't have any Colecovision cartridges yet, but starts to black screen only. I replaced capacitor 106 because of blank screen but no improvement.

Thank you, great information. I had used a similar 5 volt power supply for a Commodore 128 power supply and it had a steady rolling video interference, so good news to hear this supply is solid.

I have the pictured power supply. Unloaded it reads 5.24 volts consistently. I just like the big block power supply. Should I gut the case and put the new mean well power supply (in picture) inside or is it good to go and no danger if this model fails?

Having Atari 8 bits and a several 5200's I'd say the 5200 only if you really like to tinker and, realizing this is relative, if you can get the console at a good price. The 4 port's I have came as is and cheap because they were not testable without the power/video supply contraption so I started by doing the power mod and 2/3 were working. Next is the controllers, I did get the Best upgrade for a couple of controllers and they do work much better, great proportional control on Missile Command and Centipede but just don't work (for me) with the digital joystick games. I've built the adapter that allows use of old PC game port controls and tried with multiple PC controllers (http://www.atariage.com/5200/faq.html?SystemID=5200) and have built both of Scott Baker's controllers(https://www.smbaker.com/homemade-atari-5200-analog-controller; https://www.smbaker.com/atari-5200-playstation-2-dual-shock-controller-adapter) and the PS2 to Atari 5200 adapter is my goto better that the original controllers, but is poor on Missile Command especially; dual sticks Robotron and Space dungeon are great. The trackball for the 5200 is just out of range and still hoping someone will come up with a modern replacement for it. However, by keeping an eye out did find an as is reasonble CX22 trackball that just needed the fire button fixed and it works great with the 8 bits in trackball mode if hankering for Missile Command or Centipede. Also did an s-video mod (https://retrogame.cyberphreak.com/atari-5200/) for the 5200 and after replacing some of the set capacitors with adjustable capacitors, the video out is as good as I could want. It is a pretty satisfying machine right now, but part of that is just the tinkering and getting it to work better.