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To clarify I have an Atari 2600 4 switch Darth Vader console. On Sunday I turned on my Atari to play a bit of missile command and asteroids. When turning on the console my Tv was displaying a black-and-white image but the black-and-white switch was in color. I tried resetting the console and turning it on and off to no avail. I then proceeded to fiddle with the rf cable on the back of my tv. I have one of those screw-on adapters. As I was fiddling with the cable the color returned. Unplugging and plugging in the inside cable slowly works too. After I finished playing missile command I turned off the console to put in asteroids, after I turned it back on it was displaying in black and white again. Upon testing it later It has come to my attention that the problem is weirder than I thought. With my Atari on channel 3, I cannot get a color signal. but on channel 2 I can only by fiddling with the channel switch. I have also noticed the strange occurrence of Picture in picture mode displaying color when I am not getting color. I have even tried a replacement video cable. What's the meaning of this?

I recently decided to unbox and expand my Atari 8-bit collection. Lacking a suitable CRT television or monitor, I bought a BenQ GW2480 LCD monitor to use with a Tendak composite/s-video to HDMI converter I already had. I also moved an old SVHS VCR onto the workbench, to use with a 600XL and any computers without functional monitor ports, and I bought a pair of Atari monitor-to-RCA & S-Video cables from TBA. When I connected a 130XE to the video converter with a monitor cable using S-Video, I was disappointed to see a B&W READY prompt. I had the same result with composite and via the RF modulator and VCR, I tried the other monitor cable (which wouldn't affect RF anyway), and adjusting R38 did nothing. (As an aside, I checked the voltage off pin 17 of the GTIA, per Sams Computerfacts, and saw a range of 0V to 8V, suggesting R38 is fine.) The video converter displays color bars when no input signal is detected, I successfully displayed an old Android media streamer via composite, and the VCR's menu has a blue background over S-Video and composite, so there's no inherent problem with color between the converter's inputs and the monitor. I then checked an 800 (composite, from the monitor port, and RF) and 600XL (RF) with the same results: B&W only. I've had the 130XE for more than a decade, but the 800 and 600XL I just bought from separate sellers, and the 600XL had photos (purportedly) of the computer displaying in color on a television. It's possible all three computers now have problems with their color circuitry, but that is very unlikely, and suggests a compatibility issue with the HDMI video converter. I opened the Tendak converter and it's all surface mount components-- no potentiometers, dipswitches, or other configurables. I've ordered a new unit (different manufacturer), and will report back. Have any of you experienced this?

Recently picked up a non working Vader unit and it is using the PS I use for my modded and working 4S woody, Vader doesn’t have show any voltage at the regulator, I had extra new main cap and VR and changed those out for the heck of it and no change. What’s the proper next diagnostic steps in terms of what to check with my meter? Thanks!

130XE that was upgraded to 320K (sometime in the past) exhibiting intermittent RAM Test Failures. Sometimes it passes, sometimes one block fails and sometimes a different block fails. I've cleaned the board with alcohol and replaced the main filter cap, C1. Power supply is new from Brewing Academy. I reflowed the power switch connection, removed the SIO caps and reflowed one loose bodge wire. But I haven't touched the rest of the bodge wires yet. It looks like I'd have to remove and replace most of them since they are so tight against the chip connections. Photos are attached for your entertainment. Any advice in troubleshooting (or an alternate path for repair/upgrade) is welcome. Note: This machine has a Omniview ROM with a selector switch mounted in the case. Note 2: I've been using Side3 with this machine. When cold, the machine will boot to Side3 SpartaDOS, Atari stock OS, Omniview XE OS or a Qix 8 Bit game cart just fine. But it has a heck of a time booting to the Side3 Loader screen until the computer has been on for a few minutes. Even when warmed up sometimes the machine will lock up or not load games.

Hello all, I've been working on my first restoration and associated troubleshooting of a 7800 console. I'm flummoxed and wanted to reach out to the community to see anyone has had a similar experience. Sorry in advance for the rambling summary. ? NTSC w/ a revision B system board. Main symptom is a black screen w/ no audio -- sometimes... The Atari logo consistently shows up on power up. More below. Console all the way apart, cartridge cup removed, pins cleaned, replaced all caps after finding that the 2200uF was not in great shape. Also replaced the power regulator and power switch while I was at it. All voltages look good now at the ICs and along the main power rail. In response to the no audio issue, I've walked the troubleshooting flowcharts (many times) and typically end up on flowchart E where it mentions the encryption latch. I don't have the diagnostic or color cartridge so skipped those steps. As a result of the encryption latch tip, I've checked the logic ICs and outputs all look correct. In other words, they produce the correct results based on the input signals they receive. For the vast majority of the time the system swaps between initially working and then mostly failing -- I'd guess the failure rate is easily over 90 percent following this pattern. For the first week or so I was using a known working Galaga cartridge but then I started to get suspicious. While it always works in another console, most of the time it does not on this particular system. Furthermore, I can't reproduce the glitch with other cartridges -- e.g., Centipede and Donkey Kong both appear to always work as do a few others but I don't have a lot of cartridges to test with. In revisiting the logic chips related to the encryption latch I noticed the signal from the A12 address line from the 6502 looked stuck -- any time I see this particular signal coming from A12 it is a dead giveaway that the system will come up with the black screen and hang (it initially doesn't look like this but then will suddenly "snap" in). Here's a look at what I see on my scope for A12 -- it will stay like this as long as I leave power to the system the CPU is clearly wedged). In looking at the schematic, A12 comes off the 6502 at pin 22 and routes over to pin 8 of the cartridge slot via U4's (74LS08N) output pin #8. I re-cleaned the pins on Galaga (even removing the PCB to get a good look at them, and then re-cleaned the slot and reflowed all the pins. No luck. My next thought was that the vast majority of the time that Galaga actually runs is when the system sat powered down for a while. So, if I leave it idle for several minutes it seems to almost always work on the first power up and then fail for the vast majority of the following times when the system is power cycled with little rest in between. The 6502 does occasionally feel somewhat hot (but not too hot to touch) as I was running through other troubleshooting phases (perhaps not too surprising if it is locked up). After using some compressed air to "freeze spray" the 6502, Galaga successfully started up 10 times in a row. Once things had a chance to warm back up again the system returned to its lock-up behavior. No surprises here: My conclusion is the 6502 is potentially starting to fail but I can't wrap my head around why only Galaga triggers this behavior. The locked up signal on A12 could easily be the result of something else happening that I haven't observed. I haven't done an exhaustive walk of all address and data lines as I'm not familiar with all the low-level startup details for the system. I would find it very odd that Galaga just so happens to have a particular set of instructions that cause the system to hang. What are the odds? ? I have removed and socketed the 6502 and the same behavior continues. My plan is to start a search for a replacement Sally to see if that helps validate the diagnosis... Have I missed something obvious? Has anyone else seen similar behaviors? Thanks for any insight you can provide!

Hey all - got an issue with this ColecoVision I've been cleaning up, and it's behavior is unlike anything I've come across. And before you ask, yes, I've cleaned up the power switch and I'm getting the proper voltages ? The RAM I've heard can be suspect, but I kinda doubt RAM would be enough to cause the screen to wig out to that degree. Just wanted to see if anybody had some ideas for possible suspects.

Hello, I am in a bind. I used to do a lot of mods and console repairs on older systems, but this was over 10 years ago. I picked up the hobby again and had some successful repairs and mods. As I am learning again, I still have have a lot to learn and several projects I completely messed up. My friend asked if I would take a look at his 7800 as it was no longer working. He provided me with a ton of controllers, games and the console itself. He had tried to repair the RF unit and eventually took it out but left it there. I successfully got it up and working with an AV mod with some sound issues still and not getting pokey sound to work. I worked with all games and no real issues. One day I pulled out the system to test out a multi-cart to work on that issue and try some other games before getting the system back to my friend and no power. I tested and found the power button needed to be replaced so I did that. I also repaired the power jack and got an adapter that is lighter and worked with the system before it did not power on anymore. It still did not power on so I replaced the voltage regulator and it still did not power on. I finally found a video that bridged pins 1 & 2 for an IC chip on the top right corner of the board, and it stayed powered on when plugged in, so I tried that and it worked. A few days later I tried to turn it back on and the light came on, but now there was no sound and no video and then the power light slowly dimmed before dying after making a quiet high pitched tone until it dropped out and the light went completely dim. I unbridged the pins and for some reason now it would power on with the power button and the red light dimmed and powered off again. I then noticed the voltage regulator usually has a grounding plate (I assume) that was missing so I'm not sure what to do about that or the dimming light (is the VR getting too hot?). I replaced some of the caps and tested the rest not finding any issues with those. I tried to remove the IC chip (TC4013BP) and replace it but the ebay chip did not work even thought it did power on but no sound and video. I put the original chip back. I accidently bent the Voltage regulator and tried to remove it but was unsuccessful after getting too tired tonight. Basically I am at a loss and tired after a month or more of tinkering, digging in forums, relearning some techniques and learning more and more without success. I would just say it's a loss and maybe just not in the cards but here is the thing....I am emotionally destroyed. My plan was to get this system up and running and return it to my friend and his family, the thing is his dad has cancer and he grew up playing with his dad and his brother. I wanted so bad to get this up and running and it was working! BUT something happened and it stopped turning on and now all of this. I am asking the community not to help me figure out what to do but who would be willing to look at the system and fix my bad work and see what they could do. I am begging to get some help. I know I could buy a "new" old system but it's not the families original board or system. Please help and I am glad to pay for any service costs. I just want to get this back to him so they can enjoy and have some good memories playing on their old system again. Feel free to offer up some thoughts on what could be some issues but I would really like to see if there is anyone out there. Thank you for reading.

I've an Atari 400 that I had apart and late one night decided to install a UAV board. I then connected the power board, inserted the CPU and RAM cards, then powered on. No video signal. I checked over my wiring to figure out what I had done wrong, but the wiring was all correct. Then suddenly I realized something, with the sinking feeling as I would imagine someone might have when they hear the scraping of the belly of their airplane upon a gear up landing...I had installed the cards backwards! I know what direction they're supposed to go, but had a lapse of attention at some point. I quickly powered off, turned the cards around, and tried powering on. This time had a video signal, but a blank screen. All I can get now is a blank screen, or once in awhile, a green screen. I've checked power and signals everywhere I can think of, but everything appears to be good. I eventually figured out that all the ICs are good and it's not the power board. The problem is definitely a component on the main board. Power looks good at all cards and ICs (+5V, +12V, -5V), the frequencies are good, the O2 signal looks great at all appropriate locations, the CPU SYNC is going, address lines are all active, CAS and RAS are active on the RAM. I can't figure what where the problem is, but it's definitely one of the mainboard components. Anyone have any idea of what I might have fried that can cause this? I forgot to add, there's also no activity on the SIO. Fortunately, this was my own Atari I was working on.

Hello everyone, I have a problem with my colecovision. It worked fine when I used it last week, but when I tried to play some pepper II the screen started messing up. I've attached a video. Does anyone know what causes this issue? It's not the RF cable. VID_20210215_224823.mp4

Michael Matte sent me an article on how to troubleshoot a failing Astrocade power supply. Here is the article, followed by two photos that will help you follow the article. Keep in mind that working with the Astrocade's power supply could be dangerous; proceed with caution and be careful. Troubleshooting the Power Supply in the Bally/Astrocade Home Computer System by MCM Design February 21, 2018 A BRIEF: WHAT IS COVERED HERE This article is for the individual desiring to learn how to troubleshoot the power supply in the Bally/Astrocade home computer. Included is info and troubleshooting tips that may help locate a failure within the power supply. The following steps and recommendations will be covered in detail: - Plug black power XFMR into a low amp fast acting fused 120VAC source to help protect it and the motherboard from shorts to ground. - The pwr XFMR windings can be checked with an ohmmeter and an AC voltmeter. - The 8 rectifier diodes and 10,000uf cap C6 are not switched off by the motherboard power switch. - A basic check of the 8 rectifier diodes, using an ohmmeter, can be performed without de-soldering them. - Capacitors can be checked for shorts using an ohmmeter. - Voltage regulators with a normal input voltage, but, near or zero output voltage can be de-soldered and tested in a simplified breadboard circuit (or just replaced). - Down line caps can be checked for shorts using an ohmmeter. - A basic check on the power transistor Q1 can be performed using an ohmmeter. THE TROUBLESHOOTING DETAILS My first recommendation when troubleshooting a motherboard is to plug its black power transformer into a low amp FUSED 120VAC source. The fuse may help protect your motherboard and the black power XFMR in the event a short to ground occurs within the power supply or other areas. You probably will have to build a fused 120VAC source. Jameco Electronics sells a fast acting fuse as low as 250mA (part #69404), which is what I use in my hi-res Astrocade. A few weeks ago, I purchased a nonworking Astrocade from EBay. When I hooked it up and turned the power on, absolutely nothing happened on the TV screen. When I removed the console cover, I took just one voltage reading on a TTL chip. There was no +5V present. My second look at this Astrocade was to determine how many of the 4 DC supply voltages were actually present, if any. I just plugged in the black power XFMR into a power strip. Little did I know that the motherboard's power supply was shorted. As I was checking the 4 DC supply voltages and pwr XFMR sec AC voltages, I wasn't paying attention to the pwr XFMR which was heating up. This XFMR just kept overheating until its primary winding burned out. I learned the hard way to never again plug a Bally pwr XFMR into an unfused 120VAC source. THE POWER TRANSFORMER The XFMR's rms (root means square) ratings are indicated on its plastic housing along with the secondary wire color coding. The XFMR secondary has 3 windings wired in series. The two end windings are identical and typically rated 85mA@11.5VAC. The center winding is typically rated 1.0A@7.5VAC. The center winding is used for the motherboard's +5VDC supply. You can use an ohmmeter to check if there is a break (open) in the primary or the 3 sec windings. Use the ohmmeter RX1 range. An intact secondary winding will read nearly zero ohms and an intact primary winding will read a little higher in ohms. If the winding is open, the ohmmeter will remain at infinity. You can also check the sec AC voltages using an AC voltmeter. Disconnect the brown sec wire connector from the motherboard and tape it down. You will probably have to wind some bus wire or solid core hookup wire around the voltmeter test probe tips to make contact with the 4 color coded wire contacts. The 2 center contacts red-yel (or red-grn) are the center winding. Plug in the XFMR and measure the 3 sec voltages, end to ctr, ctr to ctr and the other end to ctr. Expect normal voltages to be a little higher than the XFMR's rated voltages because you are measuring these sec voltages with no load (disconnected). Note also because the sec windings are symmetrical, you can "turn around" that brown connector and plug it into the motherboard. It doesn't matter which way you plug it in. You can build a substitute power XFMR for the Bally black pwr XFMR. See my article in "The Arcadian", 1986, p.92-93 and 91, which is archived on the BallyAlley.com website. You can add a fuse to this substitute's primary winding. You can also place next to this substitute a quick connect breadboard strip. With some extra components like a sec fuse, bridge rectifier, caps, load resistor, etc., you can wire a test circuit to one of the end sec windings on the substitute XFMR or center winding depending on which motherboard component(s) you want to test. So, for example, you could de-solder a suspicious voltage regulator plus maybe a high capacitance electrolytic cap C6 or C1 and breadboard a test circuit to see if they are operating properly. This breadboard test technique would allow you to check specific components within the motherboard power supply without actually turning on the motherboard and risking further damage to motherboard components. I have ordered 2 Jameco XFMRs (part#2231152 and 102593) that may be well suited as a substitute XFMR. I plan to wire these 2 Jameco XFMRs and test/document this substitute configuration. I will also check to see if this configuration is ok for long term use with a motherboard. If the configuration is acceptable, the documentation will be submitted to the Bally Alley for review and possible archival. The documentation would include breadboard test circuit examples and more. FULL-WAVE RECTIFIERS The motherboard utilizes an unusual 8 diode rectifier configuration providing full-wave rectification to four power supplies, +12V (or 15V), +10V, +5V and -5VDC. Each full-wave rectifier converts the input alternating current (AC) into direct current (DC). The full-wave rectifier CR3, CR4, CR5 and CR6 is used for the +5V supply. In this case, the AC in one direction flows thru CR3 and back through CR6. The AC in the other direction flows through CR5 and back through CR4. If the secondary center winding produces 7.5VAC rms (as rated on the pwr XFMR plastic housing), the peak DC voltage would be 7.5x1.414=10.6V, excluding the diode drop off voltages. The 10,000uF capacitor C6 tries to maintain near peak voltage. When the +5V supply is operating, you will normally measure less than 10VDC across the C6 cap. The full-wave rectifier for the +12V and +10V supplies operates similarly in one direction flowing through CR1 and back through CR6 and in the other direction, flowing through CR7 and returning through CR4. The peak DC voltage would be (11.5+7.5)x1.414=26.9VDC, excluding diode drop off voltages. The normal operating voltage across the 1500uF C1 cap is under 25VDC. The voltage ratings indicated on the 1500uF C1 and 100uF C10 caps are normally 25V and 16V respectively. I have seen on the 10,000uF C6 cap ratings of 10V or 16V. I measured the voltages, IMMEDIATELY at power on, across the 3 caps on several motherboards with different pwr XFMRs and here are my observations: 1500uF C1, VC1=less than 25V 10,000uF C6, VC6=less than 10V 100uF C10, VC10=at or slightly less than 16V. The voltages across caps C1 and C6 will drop a little more when the motherboard runs for quite some time. The operating voltage for cap C10 is at or very close to its 16V rating and does not seem to change even if the motherboard runs for some time. Note that the 10,000uF cap C6 is NOT switched off by the motherboard power switch (see motherboard schematic). When the Bally black XFMR is plugged into a 120VAC source, the full-wave rectifier CR3 thru CR6 and cap C6 ARE ACTIVE. Also, you will likely see a voltage across cap C6 near or exceeding its 10V rating. I read that the voltage rating of a capacitor is the maximum amount of voltage that the capacitor can hold. Exceeding this voltage can damage the capacitor causing its dielectric to breakdown. It may be advisable to turn on the motherboard power switch IMMEDIATELY when you plug in the black power XFMR so that the voltage across C6 drops below 10VDC. Likewise, when you are finished using your Bally/Astrocade, turn off the motherboard and pull out the black XFMR (or turn off the power strip). Note also, when the motherboard power supply is turned off and the black pwr XFMR is removed from the 120VAC source, there is still a substantial charge across C6 and takes quite some time to discharge by itself. You can perform a basic check on a rectifier diode using an ohmmeter. A diode acts like a switch. When it is forward biased, the anode (P material) is positive with respect to its cathode (N material), it turns on and conducts current. When it is reverse biased, the cathode is positive with respect to its anode, it turns off. The cathode end of a diode is marked with a stripe. Checking a loose diode with an ohmmeter is easy. Just place the ohmmeter's test leads across each diode end, read the ohmmeter, swap the test leads and read the ohmmeter again. The ohmmeter will read either high or low ohms. A good diode will read low (only a few ohms, on) when forward biased and very high ohms (off) when reverse biased. A diode is shorted if both readings show zero ohms. A diode is also bad (open) if both readings indicate very high ohms (infinity). You can perform a basic check on all 8 rectifier diodes without de-soldering them and with the power off. Remove the brown pwr XFMR wire connector from the motherboard. Push the motherboard power switch to the "on" position. Look at the motherboard schematic (upper left) and use the ohmmeter to identify the line inputs 1 thru 4 and attach a label with these numbers to the metal shielding by those inputs. Place one ohmmeter test lead at the appropriate line number and the other test lead at the diode wired to that line number. Place that 2nd test lead on the diode's anode or cathode, depending on which diode you are checking. Read the ohmmeter, swap the test leads and read the ohmmeter again. If you read low and high ohms, the ohmmeter is indicating the diode is switching on and off. Repeat a similar procedure for all 8 diodes if so desired. CHECKING CAPACITORS FOR SHORTS It looks like you can check capacitors with an ohmmeter, to see if a cap is shorted. An analog ohmmeter would be preferable because you can watch the needle swing right or left. Your local hardware store sells inexpensive analog multimeters. The Astrocade mentioned above that I was troubleshooting had a shorted 15uF electrolytic C8 cap. My ohmmeter indicated it was shorted reading zero ohms. If you suspect an electrolytic cap on the motherboard might be shorted, turn off the power completely (including the black pwr XFMR) to the motherboard and use a voltmeter to see if it has a charge on it. Be careful the test probe tips don't touch other components or motherboard traces. To avoid possible shock when testing the 10,000uF cap, which may have a substantial charge on it, hook up one voltmeter test lead at a time. Avoid hooking up both test leads simultaneously with both hands. Also, don't let the pos test lead fall down onto any metal shielding which is grounded. If the cap does have a charge on it, it CAN'T be shorted. If the voltmeter does indicate the cap is charged, you can let the voltmeter completely discharge the cap. If the voltmeter reads zero volts across the cap initially, you can check it for a short. If you suspect an electrolytic cap is shorted and it has no charge on it, you can de-solder one end of it and raise that end away from the motherboard. An ohmmeter utilizes a small internal battery. So, if you check an electrolytic with an ohmmeter and that cap is not shorted and the cap will hold a charge, you will during the reading actually place a small charge on the cap. Observe polarities. You may have to put the red test lead in the ohmmeter neg jack and the black test lead in the pos jack because of that ohmmeter internal battery. Swapping the leads like this makes it less confusing (similar to testing a -5V supply). If the cap is not shorted and discharged and is able to hold a charge, you should see the ohmmeter needle briefly swing to zero and then to infinity. You can try this check just once, but then you will have to discharge the cap if you want to run another check on it. Practice this technique on a spare cap first until you get the technique established in your mind. I have tried this technique on a spare working 1000uF cap and also a 4700uF cap. I read that if an ohmmeter reads less than 500k ohms (when the needle stops swinging left) it may be leaking. Also, a damaged electrolytic cap may have a whitish deposit at the seal around the terminals. Voltage regulator input capacitors C2, C4, C8 and C11, if shorted, have the potential to burn out the black pwr XFMR. Caps C2 and C4 have a lower risk because they are wired to a series resistor. Cap C2 is likely wired to a 24 ohm, 1/2W resistor instead of a jumper as suggested on the schematic. Note Cap C8 (6.8 possibly 15uF) is wired to all 3 positive DC supplies. If cap C8 shorts, it will shut down all 3 of these supplies. Of course the 3 filter caps C1, C6 and C10 could short out and damage the pwr XFMR. This is why I highly recommend plugging the pwr XFMR into a fused 120VAC source, to help protect the XFMR and possibly other components from a short to ground. When I used my fused substitute XFMR on my Astrocade described above, the shorted C8 cap would blow out the 1A fuse in the XFMR primary. This particular substitute did have oversized XFMRS, but the substitute I plan to build mentioned above will be closer in size to the Bally black XFMR. The voltage regulator output caps C3, C5, C9, C12 and the downline "chip bypass" caps, if shorted, will at least, I believe, shutdown a voltage regulator which has some kind of internal short circuit protection. VOLTAGE REGULATORS AND DECOUPLING CAPACITORS I spent a little time on the internet trying to find some info regarding a voltage regulator's internal short circuit protection. I didn't have any luck finding info on this feature. At this time, I'm assuming it just attempts to protect the regulator should there be an output short to ground. I have seen a bad regulator with a normal input voltage, but no output voltage. A suspected bad voltage regulator could be removed from the motherboard and tested in a breadboarded test circuit. A shorted output cap or downline "chip bypass" cap would, I believe, yield a near zero voltage on the regulator's output. In the event you find a reg with no output voltage, it might be a good idea to remove the reg from the motherboard and then check the output line for a shorted cap as described above making sure first that the output line has no charge on it. If there is a little charge on the line, that's an indication no shorted cap is wired to the line. As far as I know, the +10V line has no electrolytic bypass caps wired to it. The other 3 DC supply lines do have some electrolytics wired to them, but they may not hold a charge for very long. POWER TRANSISTOR Q1 You can perform a basic check of Q1 using an ohmmeter. De-solder the end of the 240 ohm resistor R2 which will leave the base (B) of Q1 disconnected allowing you to check Q1 from the bottom of the motherboard. This transistor is a type NPN transistor and can be viewed as 2 diodes connected together at their anodes (P material) end. The joining of the two anodes would be the base (B) of Q1. You can check these 2 junctions, B-E and B-C just like checking a diode as described above. If you check the junction C-E and the ohmmeter indicates a short (zero ohms), say good-bye to your motherboard chips because the +5V power supply line most likely exceeded well over +5V which will zap the chips. REMOVE BOTTOM MOTHERBOARD SHIELDING One final recommendation is to remove the motherboard's bottom shielding panel when just taking test readings along the edge of the motherboard, even if you are not clipping a lead onto a component. I made a mistake and placed an uninsulated alligator clip on the pos (+) end of the 10,000uF cap C6 because I wanted to monitor its voltage when I switched on the motherboard power. While the motherboard power was on, the alligator clip fell and touched the metal shielding which is normally grounded. Ouch! I saw a very large spark. I was lucky because the Bally black power XFMR was plugged into my home built fused 120VAC receptacle. The 1A fuse on the XFMR primary winding blew and saved, I'm sure, my motherboard from damage. So, play it safe and remove that metal shielding. Then use a clip on jumper and ground the RF modulator metal housing to the NEG lead of that large 1500uF electrolytic C1 cap on the right side of the motherboard. Watch out you don't connect the jumper on C1's pos end. The two photos below show the locations of the 3 electrolytic filter caps within the power supply I would label as "caps of concern" because they operate close to their maximum voltage ratings. They are caps C1, C6 and C10 rated 1500uF, 10,000uF and 100uF respectively. End of document. Here are the close-up photos of Michael's Astrocade motherboard: Caps C6 and C1: Cap C10: I hope that this information proves helpful to those with failing Astrocades. Remember, working with power supplies can be dangerous; be careful! Adam

Hi All, I’ve recently worked on an Atari 400 and 800xl and installed the new Sophia 2 chips with dvi connections. Both are outputting great video now. My 400 had some issues at first running cartridges but after a few tries and cleaning some carts off it worked. My 800xl is another story though. I can’t get a single cartridge to start. Ones that I already tested as working on the 400 do not work on the 800xl. I ran the self test and all items pass. Wondering how to test the cartridge slot itself. I did use some canned air to blow out the port as well as a little 99.8 isopropyl. Anyone have any thoughts to verify if the cartridge slot is working? Are there any continuity points I can check from the cartridge pins? Any suggestions appreciated. GabeShack

I have a vader model, I've replaced the RIOT chip, the 4.7uf caps, the 2200uf cap, and the voltage regulator. Once I got it running again I noticed the video was fuzzy. I decided to do an A/V mod and picked up this kit: https://www.ebay.com/itm/Atari-2600-7800-Composite-Video-Mod-Upgrade-Kit-DIY/303092047733?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649 Side note: as others have mentioned in other forums about the a/v mod the video was dark, after removing one of the resistors from the mod circuit that solved that issue. The picture, however, is still fuzzy. I've uploaded a video showing what I mean: https://youtu.be/UXzVRivc258 Not sure where to look next, any suggestions? I have tried multiple composite cables and televisions as well so I'm pretty sure it's an issue on the board itself.

I just bought a used Atari 2600 system. It only came with one game, so I cannot troubleshoot the game itself being defective. I also cannot seem to find a relevant thread that has the same issues. I have cleaned all the contacts and switching the power on normally results in a diagonal white line that scrolls across the screen. Every once and a while I get colored bars (assuming something altered PF0-PF2 or the player sprites.) Sometimes I get a blank black screen, so it is sending a signal to the TV. Very rarely do I get a screen that could almost look like Combat playfield (but it definitely isn’t). Also, should Combat be missing a trace on the front (Pin 8/Pin 5? Or maybe the backside is pins 1-12, so pin17/pin20). What is the next thing to troubleshoot with these symptoms? Do I have a bad TIA or RIOT? Do I need to do a recap sooner rather than later to prevent any exploding capacitors?

Hi, having some trouble with my Intellivision. When you are playing a game (I’ll use Triple Action tank battle as an example), when you drive your tank to the top of the screen, a second tank appears at the bottom. Both turn and shoot at the same time and both can kill the other tank by shooting it. Any ideas would be appreciated. thanks, Marc

Hi everyone, I bought my dad an Atari Flashback 9 for christmas for us to play together. We plugged it in today and the video worked okay but there was no sound. After plugging it into multiple tvs and ports I found out that our menu was also different. I have the AR3230 model which uses composite cables, but the ports we plugged everything into are known to be functional. I'm not sure what else to do, is there a way to get the good menu and to fix the sound not working? The only suggestions on AtGames are to turn up the volume or to unplug and replug the audio cable.

2600 Left, right,up, down not working on controller. Fire works but nothing else. Both controller ports have same result. Also I have tried 4 different controllers in each port. I bought this second hand and it came this way. Don’t know where to start troubleshooting. Any info would be appreciated. Thanks

I recently managed to snag an Atari 8-Bit lot at an estate sale. I mostly bought it for the accessories it came with (since I already have an 800), but it also came with a 130XE. However, when I turn it on, it boots to the self-test. I pulled it apart and noticed the 320k upgrade had been done to it (according to a sharpie label on the RF shield, it was done in July, 1987). How do I interpret the memory test? Is there any set of steps I should take to try and fix this? I've attached pictures of the mod and the memory test screen (the white box one being tested in the photo passed).

I have an 800XL that does not respond to keyboard inputs for ESC, and the 1-6 keys. I thought I had a bad mylar but I tried two different mylars and a mechanical keyboard. When I used the mylars and the keyboard on a different computer, everything worked as it should. Where do I start my search for the problem?

So I had problems with my 2600 so I decided to try my hand at the AV Mod. I did all the work, it doesn't look great but I hoped it would work, but it didn't. Is anyone able to see what I did wrong and if I can fix it? https://imgur.com/a/xY43JRJ

Friends, I'm a long-time lurker and haven't had to post anything, because these forums are filled with good information that helped me troubleshoot just about everything for my light-sixer VCS. I have run into a problem that I cannot seem to solve on my own, nor can I find any similar problems on the interwebs. I recently bought a copy of this version of Bowling. When I first plugged it in, I got screeching sound and scrambled visuals. I cleaned the contacts real well, let the alcohol dry, plugged it back in and it was fine. A couple days later, I wanted to play it again and the screen was black and white dots. The bowler, alley, score, and pins are all visible, but the picture was awful. It improves 100% when I enable black and white mode, but c'mon, I want color! The other day, I opened the cartridge up completely and tried to really scrub the copper contacts, but I got the same result. Every other VCS cartridge I own displays full color on this console, I know that it's just this one cartridge. I'm out of troubleshooting ideas. Any of you fine folks have any ideas of what I should try next? Thanks! Bryan

I booted up my Atari 2600 JR the other day, and I found that both controller ports were unresponsive to any input from the paddles or joystick. I popped it open and took a peek at the board, and there’s no visible damage. I’m using the attached schematic and a multimeter to try and find the issue. I’ve tested C20 and L3 but they both work fine. I suck at reading schematics. What components should I be focussing on to test?

Well, I'm diving back into real TI hardware and unfortunately my luck with it is like with nearly everything else - if it wasn't for bad luck I'd have no luck at all! Anyway, I'm not here to pity myself, but would like to know what the issue is with one of the TI-99/4A's I recently picked up in as-is condition. I've attached a picture of the boot screen which shows a lot of garbage and obviously isn't working properly. Is this a video RAM problem, the display chip, or something else? Thankfully I did get a hold of one working 4A (the 4 also has problems - it powers on but has nothing but snow on the screen and a weird high pitched static / white noise going on so I don't know what's wrong with it), a speech synthesizer, and a bunch of carts including a few rare ones. Of course, it's the carts only - no boxes or manuals, but I'm still pretty happy with what I've picked up so far, along with my notations for my own reference. # in parentheses is how many I have of each if more than one: Adventure - TI (3)(cartridge only) Alpiner - TI (3)(speech) Buck Rogers: Planet of Zoom - TI (speech) BurgerTime - TI (flaky) Car Wars - TI Congo Bongo - TI Diagnostic - TI Disk Manager 2 - TI (4) Editor/Assembler - TI (3)(requires 32K)(cartridge only) Jawbreaker II - TI M*A*S*H - TI (speech) Mini Memory - TI (3) MunchMan - TI (2) Parsec - TI (speech) Return To Pirate's Isle - TI Speech Editor - TI Star Trek: Strategic Operations Simulator - TI (speech) Super Demon Attack - TI Terminal Emulator 2 - TI (6) TI Extended BASIC - TI (5) TI Invaders - TI TI WRITER Word Processor - TI (cartridge only) Tombstone City - TI Tunnels of Doom - TI (cartridge only) Ambulance - Funware Defender - Atarisoft Disk Fixer V2.1 - Navarone (requires 32K) Frogger - Parker Brothers Jungle Hunt - Atarisoft Micro Pinball II - DataBioTics Miner 2049er - Tigervision (2) Pac-Man - Atarisoft (flaky) PDM-99 (Peripheral Diagnostic Module) - CorComp Pole Position - Atarisoft Speed Reading A - Navarone (flaky) Super Extended BASIC - ? Wordwriter - DataBioTics Could have been better, but overall, I'm glad that I got at least one working machine with which to start over. I'll have to look over the threads here to see what the best path forward would be for getting 32K RAM added, as well as storage.

Hello, So first a bit of a disclaimer - I am a bit of a noob when it comes to electronics repair et all - my soldering is crap, and I am definitely learning this stuff as I go along - so please pardon what I am certain is going to be apparent ignorance. I have a 2600 jr rev E which is displaying poor colors (screen appears mostly greyscalish/monochromatic with some yellow/green tinting on the sprites. I tried adjusting the color pot, which you can tell is affecting the underlying colors but onscreen the result is just changing the grey levels so the screen still remains mostly monochromatic. Adjusted the RF pot to no effect either. Low hanging fruit (IE assumption on my part) seemed like it might be a bad cap, so I purchased a recap kit from console5 for the JR. Replaced the caps (polarity on the caps is correct) Turned the machine back on, colors were perfect for 1 second, and then it reverted to the same symptoms, only this time with audio distortion as well. Ordering ESR meter from amazon to check caps, but while I wait the two days for prime to deliver, I would love to get the communities input. 1) What should I be checking to troubleshoot this? 2) I have another 2600 jr that works (I haven't opened it yet so not sure what rev the board is) - so I could desolder and swap TIA if that's appropriate (my inclination is to socket the chips as well, my board has all three chips soldered to board - so if there is room, I think I will socket them) 3) This is probably a really dumb question - but I am curious all the same, the Jr cap kits comes with new caps for C20, C26, C27, C29, C37 c26 is obviosuly the big cap @ 2200uF 16v the other four c20, c27, c29, c37 are listed @ 4.7uF 35v in the console5 wiki (https://console5.com/wiki/Atari_2600) That said the kit from console5 only comes with 3 replacement caps instead of four. My particular revision lacks c29 so 3 caps were fine, but are there revisions which have all four caps on them? Or does each board revision have only a combination of three of those four caps? . Thanks Xamfear

I got my old Intellivision II out of the garage and decided to hook it up again. It's been unused for about 20 years. When I turn on the Intellivision II, the power light comes on, but I just get static on the TV. I've tried both Channel 3 and Channel 4. I've tried two different cables, two different "Game / TV" boxes, and two different 300-Ohm-to-75-Ohm converters, but none of it made any difference. Any recommendations on the next step in troubleshooting this problem? For no particularly good reason, I'm wondering if the problem is the RF modulator. (My only real justification for thinking this is that the output jack on the RF modulator is bent at a bit of an angle.) So I'm thinking about getting an AV mod and seeing if that fixes the problem. Is that a good next step, or is there something else I should try first? Thanks!

Hey guys. I've seen a lot of good help on this forum that I've used to help me diagnose my Atari 2600 4-switch that has not worked ever since I tried to install a widely used composite mod. (Kit Link Here) I installed it using an instructable (Instructable Link Here) I followed all instructions including removing q202, r209, r222, and c205, aaaaand... nothing it didn't work. (note: when I say nothing, I mean the TV says no signal.) I suspected bad connections but that wasn't it. I tried re-soldering the old components and that did something for a while but then it stopped. Next I thought that it wasn't getting enough power so I checked the power supply and 5v reg. Both were just fine except the 5v Reg had 2 of it's pins crossed. After uncrossing them I got some video for about two seconds and then it quit. (see attached video) I thought it was the chips now so I replaced all 3 (TIA, RIOT, and CPU) and this put me back to the same old no signal screen. I tried the old chips on a working system (w/o composite mod) and they gave a black screen. Not sure what to do at this point. Nothing is abnormally hot. Maybe my somewhat noob soldering skills maybe be a problem Cheers, kalgran Glitching.mp4