Centurion13

Turns out the 5v regulator failed sometime during the testing phase. I replaced it AND the 12v regulator, but wonder if the transformer failed and took them with it. Also wondered if the 5v regulator's failing took something on the motherboard with it. Too much time and money invested. The unit I was working would have brought in $60. I spent that much on a replacement unit to get this one going and another $25 on the A/V module. I did this because I wanted to please this particular customer, and now I will have to simply eat the expense and disappoint my customer. I removed the AV module, put the unit back together and am returning it to the shop today. We're not refurbishing these monsters anymore. They are not cost-effective - too many interactive subassemblies (the transformer, the power supply board, the motherboard, the RF module, the RF shield, the game cartridge plug, the game cartridges themselves) multiplies the number of possible fail points to the point where troubleshooting it becomes a crapshoot - and a poor one at that. Never again. But thank you all for trying to help! Regards, Steve

What I meant by that comment was this : when I plugged the coax cable female plug into the RF box's male coax jack, I needed to press the plug slightly to one side before a nice clear picture appeared on the screen. The box's male coax jack itself rattles a bit and is a tad loose. Cent13

I was tasked with refurbishing a Matell Intellivision. No problem, I do other game machines all the time. So I found out it doesn't work. Okay. Bought one that did off Ebay. Plugged the Ebay unit in, the RF signal is dodgy due to a crappy RF plug, but no problem, it comes in just fine after jiggling. . So I re-capped the power supply and the motherboard. Then I added an A/V mod board from a trusted source in Turkey. I've used his boards before on other machines like the 2600. Turn the machine on, the screen goes black. Nothing. Tried different carts, same thing. I checked my connection points, all my solder joints and the polarity of the replacement capacitors. Everything is just fine. Still nothing but a black screen. WTH? I mean, other than replacing the voltage regulators, I got nothing. The damn thing worked before I re-capped and installed the A/V module. Neither is a machine-crippling change. Can someone please help me shed some light on this? It's very frustrating. I have two spare units that are certified not to work, as sources for spare parts. Is there something that could have gone bad while I was doing my upgrades? Regards, Cent13

Well, the 4-switch 2600 worked fine with all my carts when first tested. Then I made the A/V module, connected it and removed the resistor/transistor/RF box. Now it doesn't work at all! Checked for spattered solder bridging circuits, cold solder joints, bad regulator, components soldered only on one side of a two-sided board, broken wires, component polarity, etc. I replaced the electrolytics with new ones, same values. Going to check the module build next and the continuity of all the wires. After that, I am about out of ideas. Any thoughts? Similar issues? This is getting to be quite annoying. Cent13

I replaced the voltage regulator, along with the three electrolytic capacitors, as the first step in refurbishing the unit. I am going to pick up a new transformer, something that produced only nine volts versus the 14-15 I am getting from the original unit. Cent13

Well, I tried the power supply on a four-switch unit. Works fine. Then I tried the six-switch unit with a swapped-out RIOT chip from another 6-switch unit. No luck. I think I will just wait on the 6-switch unit... I have plenty of four switch units to work on for the time being. Cent13

I have Combat for my 2600, and it works fine. But neither Donkey Kong or Battlezone will stay on for more than ten seconds... then they shut off and I am left with a blue screen (I have an A/V mod). Can someone tell me what might be going on here? STeve

Hate to practice thread necromancy, but I have been approached by a guy who wants ALL his Atari 2600s refitted for A/V RCA connections. I have the circuit diagram and am no slouch with a soldering iron, but from what I have seen in this column, that circuit deals only with the video signal. What connections are necessary for the audio portion? Or is it simply taken right off the chip? I see connections leading into and out of the board for the audio but do not see anything on the circuit schematic dealing with this. Regards, Cent13