Scoticus

She's dead Jim.... At 8:23 pm on Wednesday February 11th 2015, my Intellivision passed quietly into that dark night. She survives by her loving mother and father, and two siblings who never had the joy of playing with her. She brought joy to all around her, although only two at a time. She had many different hobbies, including all types of sports, casino games, night stalking and, of course, illuminated frisbee. She would light up any room she was in (hooked up to a TV with the brightness set to high). In her short 34 years on this planet, she fought through hundreds of wars, and saved the earth from aliens, demons, and asteroids, but would still be humble enough prepare burgers with all the fixins. Just like the rest of us, she encountered many pitfalls in life, and occasionally felt like she was on thin ice, but was always willing to bump and jump her way back up. She will be missed by all who knew her, until she's replaced of course. Ok, got that out of the way. So here's where I'm at. Replaced the C26 cap, and it didn't fix it. Was pretty much out of options at this point, so wanted to see what would happen if I drove the reset pin high, and BAM! Space Armada!! I know it likely isn't supposed to be blasted with unimpeded 5vdc, so tried multiple diffirenet ways to limit voltage/current, but it would only work if essentially blasted unimpeded. Over time, I think this was two much and it slowly just stopped working at all. Here's my theory, the chip likely is held at logic high internally. When the reset button is pressed, it triggers a reset on the falling edge when the reset button drives the pin to ground. When the reset button is released, the capacitor discharges giving the reset pin a little momentary bump back up to logic high, where it's then held high internally. So if the internal circuitry was fried and unable to hold it high, I was able make it work by forcing the pin high, but at the same time, it likely isn't designed to have full 5vdc forced into the pin for extended periods, so doing that likely slowly fried the internal circuitry that was still working. I hope this tragedy at least adds something to the knowledgebase. I may be way off, but without a decent datasheet, or internal schematic, there's no way to know for sure. The datasheet from the manufacturer is a whopping 2 pages, and is more just for advertising. So where to go from here. I'm just wondering if you do have a spare board Bradd, and what the costs would be in procuring that? Once I get everything working, I'll likely have some spare working components, so if I can use those to help anyone else get going, I would be happy to do so for the cost of shipping. Either way, thank you all for your help, didn't work out in the end, but learned a ton!

Thank you all for the great advice! For starters, thank you for the link to the schematic, been staring at it for an hour now. None of the transistors have any sign of fatigue or burning, but could still be the issue. I believe I have some 2n3906's at home, but am trying to avoid desoldering because of the condition of the board, but will definetly be trying that at some point as a last resort. If there was any sign of fatigue though, replacing them would be a priority. I'm hesitant to look at the regulators as the cause, as I am pretty sure that as they fail, hey either head towards a dead short, or open, but neither should effect the current without seeing a change in voltage, and the voltages are dead on. At least I think this is the theory... I'm definitely leaning either towards the STIC, or the reset circuit around it, as nothing at all is happening when I press reset, but the screen is going black showing that sync is likely being generated by something. I'm having a little trouble figuring out the circuit though. It appears as though 5 volts is fed into the reset circuit, past a 10k current limiting resistor, then through a bipolar capacitor (C26) to the STIC. The reset button connects the pin to ground, so drives the pin low when the button is pressed. What my confusion is, wouldn't the capacitor act like an open circuit, and block the 5VDC, keeping the pin low and essentially making the button redundant? I know I'm missing something in my electronic theory, as I always struggled with capacitance and inductance, but a bit of googling also seems to have other confused about this. This is a longshot, but if anyone happens to have a working INTV, what is the voltage at the RSTIN pin (14) during normal operation? Also, just wondering what happens if you hold the reset button down on a working unit, does it flash and stay black, or does the screen show static as long as the button is held down? If 5v isn't getting to that pin, it would likely work the same whenever I turn it on as if the reset button was held down.

So I just got my first Intellivision on Saturday. Me and my wife were having a retro video games night and one guy brought an Intellivision with a ton of games. It worked fine for a few hours, then when I took a break from some mario party to play it, he said it just wasn't working anymore. He said that he hadn't used it in forever, but it did work great for a couple of hours. He said he was moving to Germany so planned to leave it all there (WOOHOO!). I'm dying to play this thing, so I've been troubleshooting the last couple of days. All I'm getting at bootup is the black screen, if I try to reset, nothing happens, screen just stays black. I've followed everything I can find on this site and still same issue. Here's what I've tried troubleshooting so far: Cleaned cartridge and port with brass cleaner Checked voltages, all appear normal (according to other posts on here) Replaced ribbon cable with wires (continuity was ok on ribbon cable before, but replaced anyway as it was looking a little rough) Opened sarcophagus (EVIL SOLDERING!) and reseated all socketed chips Recapped all electrolytic capacitors (except c26, which is a bipolar electrolytic (who ever has them on hand?)) Removed reset button (the metal plate thing) and tried shorting directly, still no change on screen Tried carts in about 1000 different levels of insertedness, no changes on screen Cried a little Opened and cleaned contacts on power switch, got rid of the small amount of static on screen, but still not loading and no flash on reset Tried Atari 2600 on same rf box, worked fine Played Atari for a bit to make it work out of jealousy. Fun but ineffective. Seem to be getting voltages on multiple CPU pins, but don't have the patience to go through all connections for proper voltage Performed all troubleshooting steps with controllers removed. My main concern is that there is no response from the screen when pressing reset (not saying it has anything to do with the reset circuit, actually probably doesn't, but does show that everything is not working logical captain). I'm just hoping anyone out there can help, as I'm dying to play this, and I live in Ontario Canada which makes the shipping bloody expensive since most of the sales of these on ebay are in the US, so would really just like to get this one fixed. Also want to keep the desoldering to a minimum as some of the pads were lifting from the heat of desoldering (don't worry, checked continuity after lifting to make sure trace didn't break). Sending my love in advance to anyone who can help.