MaximRecoil Posted October 17, 2015 Share Posted October 17, 2015 In the upper right hand corner where I brightened the image. It looks like a giant resistor. None of my 3 light sixers have it. What is it, what's it for, and does it ever go bad? Quote Link to comment Share on other sites More sharing options...
Keatah Posted October 17, 2015 Share Posted October 17, 2015 If those colors are accurate it looks like a 68-ohm resistor. And my guess it is connected to the regulator and a further guess is it helps the regulator stay cool by bearing some of the load, if it is wired in parallel with it. Quote Link to comment Share on other sites More sharing options...
7800fan Posted October 17, 2015 Share Posted October 17, 2015 Resistor usually doesn't go bad unless it turns black and smells like something burned. Quote Link to comment Share on other sites More sharing options...
DanBoris Posted October 17, 2015 Share Posted October 17, 2015 If those colors are accurate it looks like a 68-ohm resistor. And my guess it is connected to the regulator and a further guess is it helps the regulator stay cool by bearing some of the load, if it is wired in parallel with it. Yep, it's in parallel with the regulator, and as the schematics note, it's not on all systems. Quote Link to comment Share on other sites More sharing options...
MaximRecoil Posted October 18, 2015 Author Share Posted October 18, 2015 Okay, so that resistor could completely fail (or be removed) and it wouldn't make a difference at all with regard to the Atari functioning properly. It does seem like a good idea though, to make life easier for the 5v regulator. I guess it got ditched as an unnecessary expense. So the 1 after the slash means 1 watt? Quote Link to comment Share on other sites More sharing options...
Keatah Posted October 18, 2015 Share Posted October 18, 2015 The versions of the board don't have it. But they have a different circuit though. Quote Link to comment Share on other sites More sharing options...
Andromeda Stardust Posted October 18, 2015 Share Posted October 18, 2015 Okay, so that resistor could completely fail (or be removed) and it wouldn't make a difference at all with regard to the Atari functioning properly. It does seem like a good idea though, to make life easier for the 5v regulator. I guess it got ditched as an unnecessary expense. So the 1 after the slash means 1 watt? I wouldn't recommend stressing the 5V regulator by eliminating that part. Two cents. Quote Link to comment Share on other sites More sharing options...
MaximRecoil Posted October 18, 2015 Author Share Posted October 18, 2015 (edited) I wouldn't recommend stressing the 5V regulator by eliminating that part. Two cents. I don't plan to. As I said, I think that part is a good idea; a nice little example of the over-engineering that went into the early, American-made 2600s. Edited October 18, 2015 by MaximRecoil Quote Link to comment Share on other sites More sharing options...
Osgeld Posted October 18, 2015 Share Posted October 18, 2015 and yet they never put a reverse voltage protection diode in the system ... and if it was over engineered in the first place the voltage regulation wouldn't be stressed to the point where they thought a kludge would help Quote Link to comment Share on other sites More sharing options...
MaximRecoil Posted October 18, 2015 Author Share Posted October 18, 2015 (edited) and yet they never put a reverse voltage protection diode in the system ... and if it was over engineered in the first place the voltage regulation wouldn't be stressed to the point where they thought a kludge would help It isn't under much stress, even without that big resistor in parallel with it. It only has to deal with 9 volts and a couple hundred mA. That's why it is a case of over-engineering, because that regulator would last a very long time even without that resistor. A common modification to old Mopars is to replace the stock electromechanical voltage regulator feeding the gauges (which has a tendency to stick closed, allowing constant full voltage through, and quickly frying the tiny nichrome wire in the gauges, rendering them dead) with a 7805 regulator (sometimes the 1.5 amp version of it instead of the 1 amp version used in an Atari 2600). A heat sink and a small electrolytic capacitor (e.g., 10uF) is used with it (to help protect against voltage spikes), but there is no resistor to share the load, so it has to deal with the up to 14.4 volts from the alternator. It is also subject to the temperature extremes and vibration typical of a car environment. People have been doing that modification for at least 15 or 20 years, and I haven't heard of anyone having the 7805 fail in this application yet. I had that modification in my '69 Charger for a few years without issue, but I recently replaced it with something better which a company had specifically designed for the application (link). Well, they are better in the sense of performance characteristics (fast gauge response and such), but since those have been reported to fail by plenty of people, I wouldn't say they are better than a 7805 from a durability perspective. My favorite bit of over-engineering in the heavy sixer is the 3/8" thick plastic in the bottom half of the case. That's almost comically over-engineered. That's 6 times thicker than the plastic used for the case of the e.g., NES, and 3 times thicker than the plastic used for the Atari light sixer and 4 switch models. As for reverse voltage protection, how is it even possible to apply reverse voltage with the OEM power supply and an unmodified Atari? Edited October 18, 2015 by MaximRecoil Quote Link to comment Share on other sites More sharing options...
Osgeld Posted October 18, 2015 Share Posted October 18, 2015 (edited) well 2 situations come to mind, one being the rectifier failing inside the wall wart, the second is plugging in the system while the pack is plugged in there's a breif moment of short circuit which exposes the slight possibility of it happening it would also drop .7 volts off the input without generating heat making the regulator work a little bit less Edited October 18, 2015 by Osgeld Quote Link to comment Share on other sites More sharing options...
Andromeda Stardust Posted October 19, 2015 Share Posted October 19, 2015 The full wave bridge rectifier on the NES is an example of over-engineering. Unregulated power supply, plus, minus, DC, AC, 7 volts up to around 12 or so and it will work great. The 3/8 inch plastic case on the heavy sizer is not over-engineering. That's just being wasteful. Quote Link to comment Share on other sites More sharing options...
MaximRecoil Posted October 19, 2015 Author Share Posted October 19, 2015 (edited) The full wave bridge rectifier on the NES is an example of over-engineering. Unregulated power supply, plus, minus, DC, AC, 7 volts up to around 12 or so and it will work great. The 3/8 inch plastic case on the heavy sizer is not over-engineering. That's just being wasteful. Of course it is over-engineering; i.e., it is way stronger than it needs to be for normal usage. It would be like making passenger car body panels out of 1/4" thick steel plate, or framing an ordinary house with 8" x 8" oak lumber. All cases of "over-engineering" can be considered "wasteful" from a certain perspective, since their full capabilities will go to waste most of the time, by definition. Another question: are these both .22 uF, 100v capacitors? One is clearly marked "0.22" and also has the voltage clearly marked, while the other has "224" in it (which means .22 uF), but no voltage marked. In my light sixers, there is only 1 of these green "chiclet" capacitors, and they are marked: 224K 100V Edited October 19, 2015 by MaximRecoil Quote Link to comment Share on other sites More sharing options...
Andromeda Stardust Posted October 19, 2015 Share Posted October 19, 2015 Of course it is over-engineering; i.e., it is way stronger than it needs to be for normal usage. It would be like making passenger car body panels out of 1/4" thick steel plate, or framing an ordinary house with 8" x 8" oak lumber. All cases of "over-engineering" can be considered "wasteful" from a certain perspective, since their full capabilities will go to waste most of the time, by definition. The president rides in an armored limo. I don't think the thick steel plating on the doors or extremely thick plexiglass would be considered "waste" if it stops a well aimed armor piercing bullet from killing the POTUS. But for a regular passenger car, yeah, it would be wasteful. Quote Link to comment Share on other sites More sharing options...
MaximRecoil Posted October 19, 2015 Author Share Posted October 19, 2015 The president rides in an armored limo. I don't think the thick steel plating on the doors or extremely thick plexiglass would be considered "waste" if it stops a well aimed armor piercing bullet from killing the POTUS. But for a regular passenger car, yeah, it would be wasteful. Well that's the thing; a useful scenario can be imagined for most cases of over-engineering, which is why it is only "wasteful" from a certain perspective, i.e., wasteful most of the time, because that's what over-engineered means, i.e., exceeding normal requirements. With regard to the 3/8" plastic on the heavy sixer, there are instances where it is useful. For example, this is one of my light sixers: It was like that when I got it a few years ago, and is the reason I got it so cheaply. I have no idea how it happened, but it is a pretty safe bet that it wouldn't have broken there had it been a heavy sixer, due to the plastic being 3 times thicker. So in that particular instance, it wouldn't have been wasteful, because it would have prevented breakage. Quote Link to comment Share on other sites More sharing options...
Andromeda Stardust Posted October 19, 2015 Share Posted October 19, 2015 (edited) Well that's the thing; a useful scenario can be imagined for most cases of over-engineering, which is why it is only "wasteful" from a certain perspective, i.e., wasteful most of the time, because that's what over-engineered means, i.e., exceeding normal requirements. With regard to the 3/8" plastic on the heavy sixer, there are instances where it is useful. For example, this is one of my light sixers: It was like that when I got it a few years ago, and is the reason I got it so cheaply. I have no idea how it happened, but it is a pretty safe bet that it wouldn't have broken there had it been a heavy sixer, due to the plastic being 3 times thicker. So in that particular instance, it wouldn't have been wasteful, because it would have prevented breakage. I recently plugged up my NES to playtest some games. I picked up my NES, and picked up my 4-switch Atari, and the NES was still notably lighter. Either the NES used a lot less materials, or it was because I threw away the shielding due to it interfering with all the mods I had installed... http://atariage.com/forums/topic/243492-is-rf-shielding-really-necessary/ Edited October 19, 2015 by stardust4ever Quote Link to comment Share on other sites More sharing options...
MaximRecoil Posted October 19, 2015 Author Share Posted October 19, 2015 (edited) I recently plugged up my NES to playtest some games. I picked up my NES, and picked up my 4-switch Atari, and the NES was still notably lighter. Either the NES used a lot less materials, or it was because I threw away the shielding due to it interfering with all the mods I had installed... http://atariage.com/forums/topic/243492-is-rf-shielding-really-necessary/ The plastic that the front-loader NES case is made out of is only about 1/16" thick, about half the thickness of the light sixer and 4-switch case plastic. The NES RF shield probably weighs a couple/few ounces at best; it is very thin sheet metal just like the shield in the 4-switch Atari (though the NES shield is larger than the 4-switch shield). The NES does, however, have that spring-loaded cartridge tray contraption inside, which adds weight. The light sixer has a relatively thick-walled (about 1/8") cast aluminum RF shield, which makes it weigh significantly more than the 4-switch. The heavy sixer has the same cast aluminum shield, but its screw-on aluminum cover/lid is twice as thick as the light sixer's cover (1/8" vs. 1/16"). I just did some weighing: 4-switch woodgrain: 2 lbs., 11.7 oz. Light sixer: 3 lbs., 6 oz. Heavy sixer: 4 lbs., 7.9 oz. NES front-loader: 2 lbs., 12.5 oz. All of those consoles are stock, and the light sixer I weighed isn't the one with the broken corner, which would weigh slightly less for obvious reasons. Since the NES weighs only 0.8 oz. more than the 4-switch Atari; removing its RF shield would definitely make it lighter than the 4-switch. Also, don't you have a big ferrite choke in your Atari, along with a section of RG-6 coaxial cable and a panel-mount F-connector? That adds several ounces of weight. Edited October 19, 2015 by MaximRecoil Quote Link to comment Share on other sites More sharing options...
Andromeda Stardust Posted October 19, 2015 Share Posted October 19, 2015 Since the NES weighs only 0.8 oz. more than the 4-switch Atari; removing its RF shield would definitely make it lighter than the 4-switch. Also, don't you have a big ferrite choke in your Atari, along with a section of RG-6 coaxial cable and a panel-mount F-connector? That adds several ounces of weight. Yup. The ferrite choke does add some weight to it. Another thing is the grooved top panel in the Atari will add more plastic simply due to it's unique shape. My NES now has the Blinking Light Win straight loading tray. It's structurally comparable to the original loading tray. Since I installed the BLW, I threw out the upper shielding. The lower shielding had to come out when I installed the CopyNES breakout board. That does add a slight amount of weight but is likely countered by the shielding I discarded. I attempted to Dremel out a rectangular hole from the bottom shield to fit around the CopyNES but I ended up destroying the shielding. So the bottom shield is gone and the top is removed. Probably the shielding made the biggest difference but that sheet metal is thin. Quote Link to comment Share on other sites More sharing options...
atari-dna Posted November 9, 2015 Share Posted November 9, 2015 2W, 68ohm 5% Carbon Composition resistor. Value likely to have drifted in 30 years. Quote Link to comment Share on other sites More sharing options...
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