low_budget

The PCB is almost ready for manufacturing. I'm making progress on the ground plane and will do some final error checking first. The reset circuit is from the Famicom since there is no lockout chip. The reset pin of the PPU is tied to 5v. The sound circuit can be configured a variety of ways. By default, the audio signals have no mixing and are amplified separately. By adding resistors or potentiometers, the amount of mixing between channels can be adjusted. Auxiliary sound input from cart pin 54 can be mixed with the NES output 1 or 2 by adding a jumper. I recently acquired a Nintendo Vs. Duck Hunt arcade board, so I have a RGB PPU for testing the RGB. I'll update again when I get a prototype finally. Normal manufacturing time is 14 business days.

It seems this project may take a little longer than I expected. I am finding ways to shorten traces and remove vias. I'm taking my time because I keep thinking of ways to improve the board design. The Super 8 should be compatible with most if not all NES accessories. I am working on making it compatible with the Powerpak. I can't say for sure until I have a prototype for testing. About fitting a Colecovision in a polycase AG-85, it would be very difficult but not impossible. The Colecovision has more chips than a NES like a BIOS and separate sound chip.

I had some of the v2.1 PCBs made. They're pretty small compared to the other v2.x boards so they should fit in most if not all Atari 8 bit computers. If anybody is interested, PM me.

There are a couple reasons I decided to try this project: 1. To see if I could do it 2. Combine the best features of the various NES systems 3. Improve the audio / video output I'm making the PCB to fit in a polycase AG-85 case. So far so good. It's also available in 3 colors. I'm not that familiar with how CopyNES connects to the NES. I will look into it eventually but right now my goal is a NES with 100% compatibility and improved audio/video. Since the supply of original arcade NES CPU and PPU chips is dwindling, I'm making the Super 8 so it can use parts from the original NES. I was able to remove the CPU and PPU from a NES without damaging them. When used with the NES composite PPU, the picture should be improved. When used with a compatible RGB PPU, it will have the amplifier on board so it can output RGB to a VGA, component, or s-video converter. In the future, I may make an add-on board for a JAMMA connection. I only plan on making 3 prototype boards at the moment. That way I can determine if corrections or improvements need to be made. I enclosed a list of the major wire connections to CPU, PPU, Memory, 74LS139, 74HC373, etc. If somebody notices any errors, please let me know. I'm using a THS7314 for the RGB amp, a LM4808 as the audio pre-amp, and the Texas Instruments PTH08080W regulator for 5v power. I couldn't find a 2k x 8 SRAM chip used in the original NES, but I did find a DIP package 32k x 8 SRAM chip that should work if I tie the unused address pins to ground. I'm not sure if I will offer these for sale or not, it depends on how well my first 3 prototypes work. If I do sell them, they will likely be assembled PCBs minus the CPU and PPU. NES Wire Connections.rtf

I meant no power led, not reset button. it's late and I'm tired.

I decided a couple months ago to design a new Nintendo NES circuit board. I was annoyed how Nintendo couldn't seem to make a perfect NES console. The front loader is big and has the stupid lockout chip and ZIF connector. The top loader is rare, has no reset button, and crappy RF video. Mods exist to fix some of these issues, but I kinda think of them as a band aid fix. I've been getting better at my PCB designs, and wanted more of a challenge than the Atari s-video kits I've been building. Here's the features I want to include in my board design: Original CPU and PPU chips at the same clock frequency. Composite or RGB PPU chips can be used (has amplifiers on board for both.) Better sound pre-amplifier with separated audio channels (can be mixed if desired.) Top Loader! Smaller, board measures 6-1/2" x 4-1/4" without need for RF box. Modern switching 5v regulator. I found a NES schematic, but it has several errors. So, I've been checking the connections on a NES pcb that I removed most of the components from. Progress so far: Modern replacements found for memory and other components. Cart slot, memory, CPU and PPU connections complete. Controller input connections done. CPU/PPU clock circuit done. Video and sound amplifier circuits done and laid out. Need to do: Find replacements for diode arrays DA 1,2,3,4 Re-check connections multiple times to avoid mistakes General board layout cleanup Add ground plane to PCB My plan is to make 3 prototype boards to make sure everything works. I'll keep this page updated. I have a lot of time and money invested, I really hope it works! I hope to have the prototype boards ready in a month or so.

I uploaded the schematic of my Masterplay Clone for the Atariage community's modding pleasure. It uses only one IC and a few other components making it simpler to build than other schematics I've seen. It also works with more games than a real Masterplay. Compatible with Atari 2600, Sega Master System, and Genesis controllers. Notes: I recently began adding the two diodes, which seem to improve stability. The 0.1uf capacitor should be mounted close to the 5v input of the DG413. The 10M and 22k resistors can be altered for max/min resistance values, although these seem to be in the sweet spot. Pins 1-8 of the Atari joystick connector go directly to the keypad or a DB 15 pass-through connector. The 1M pots are for adjusting the center (neutral) position on each axis. +5v power is provided by pin 12 of the Atari connector. Free to use, just please contact me if you want to mass produce them for sale or something.

I installed the v2.2 s-video mod board in my 800XL and found the picture to be quite good, better than either version of the v2.0 board's schematic. There were no hints of vertical lines. Due to the limited height clearance, I connected it to the lifted pins of the GTIA with wires. I have a new version 2.1 of the PCB designed without the 40p DIP pass-through specifically for most (if not all) Atari 8 bit computers. It installs like v2.0 but is smaller and uses the newest schematic. I'm not sure if I want to have it manufactured unless there is enough interest. If anybody is interested in this improved Atari 8 bit s-video mod, PM me and if I get enough requests I'll have it made. Not the best screenshot, but I currently don't own any Atari 800 games

I haven't tried it, but I believe if the GTIA socket on the Atari PCB is removed, the v2.2 PCB is assembled in the thin configuration, and the top RF shield is left off then I believe v2.2 will fit, although it will be a permanent installation. It's certainly not how I hoped it would have to be installed. When installing the v2.0 PCB in my $11 Atari 800XL, I noticed faint vertical lines that weren't there on the Atari 5200. I assembled the kit as originally designed (with the chroma circuit nearly identical to the Atari 800) and the lines were just barely visible with s-video. No lines are present on a CRT, just on a LCD HDTV. I'm not sure why that is, possibly using the original monitor port with poor FR shielding? Even with faint lines, the picture is still 10x better than original. I couldn't believe how bad the stock 800XL video was. On the Atari 5200, the modified circuit had slightly better picture. Weird.

I recently bought an Atari 800XL on ebay for $12 and was going to install the v2.2 kit in it. Unfortunately there isn't enough height clearance. So far I know v2.2 will not work in the 400, 800, and 800XL. I did install the v2.0 kit and it worked well though. I used the original monitor port by connecting the missing chroma wire and removing 2 inductors linking the port to the original video circuit. I couldn't find a monitor cable with TV style s-video connector and composite so I made one. I removed the RF modulator so the board would fit easily. Otherwise it looks like a stock 800XL. I'm down to four v2.0 s-video PCBs left. I may have another run made if there's enough demand, but I'll take my time before I do.

There was a recent post about the 4 port switchbox: http://www.atariage.com/forums/topic/198464-5200-switch-box-pcb-question/ The only time I think repairing a switchbox would be worth it if it's a system in collector condition with box, etc. Like another poster said, are they really worth fixing if a power mod is probably easier? Also, I can imagine the picture would be better without 12v traveling through the same conductor as RF.

I think the Vita hardware is great. The screen, controls, powerful CPU and GPU, are impressive. Sony did a great job in this regard. The software is a different story. The OS is pretty basic and lacking features. Firmware updates have yet to improve anything. It had some great launch games, but there hasn't been much released since then. I know it takes time to develop a good game library, but I have no interest in any recent releases. The Vita store is bad. You'd think sony would put more effort into this. None of the games show any screenshots. The movies are way overpriced and take up expensive memory space. The downloadable vita games are only slightly cheaper than retail releases and use up the expensive memory space. I don't understand why a 3g model was even released. Sony needs to decide if they want a device that could potentially replace a smartphone or not. The data plans are too expensive. At least a Youtube app is coming out. I don't use my Vita very much. I use my CFW PSP much more. Time will tell if the Vita was a good buy. It sure doesn't pay to be an early adopter.

Ok it seems installation of v2.2 in Atari 400 and 800 computers might not be possible. I was able to reduce the board's thickness by laying down the transistors and removing the on board GTIA socket and 22uf capacitor. The GTIA will need to be soldered to the mod board in the "thin" configuration. Here are the installed dimensions: PCB is 2-3/8" x 2" The mod board sticks out 1-1/8" above the GTIA when installed (on the pin 21-40 side.) There is 3/8" clearance below the mod board for existing components. Installed height is 7/8" for the standard board with GTIA socket. Installed height is 11/16" when assembled in the "thin" configuration. I do not have an Atari 400 or 800, so if somebody could measure the CPU board to case clearance, that would be cool! I'm also working on installation instructions for v2.2. If anybody is interested in trying out the v2.2 circuit to see if it physically fits in their Atari computer, I could send them a kit for cheap, and if it doesn't work I will of course accept a return with refund. PM me if interested. Until I have better knowledge of compatibility, I'm going to sell this as an Atari 5200 s-video kit. Some more info about v2.2: The luma, sync, and color pins do not pass through, so the original video circuit is completely bypassed (no RF out.) There are jumpers on the bottom of the PCB to allow 5v and ground to tap off the Atari's GTIA socket. This kit has the best picture quality I've been able to achieve; it's near perfect in my opinion. COL now passes through the buffer Has gold plated header pins for good connection Each output can drive up to two video loads I will probably offer the kit assembled in standard and thin configurations. Regarding the v2.0 kit, the signal wires coming from the GTIA are digital, so there shouldn't be much interference. I used wires about 3" long in my install. As a general rule: the shorter the wires the better. I'm not sure what is causing the color difference in Faicuai's system. I simply adjusted the color delay potentiometer until the colors looked right. There seems to be a narrow range where brown is displayed correctly. I use Joust to calibrate the color delay. The platforms are green or red if the adjustment is off.

Version 2.2 of the Atari 5200 s-video mod is finally ready. The schematic is slightly different than v2.0, this time COL is buffered. Installation is much easier since this circuit plugs into the GTIA socket and the GTIA plugs into the mod board. It also has the option (via jumpers on the bottom) to power the mod board from the socket to eliminate two more wire connections. I haven't done this yet because I'm not sure if it can handle the mod board's current draw (about 70mA.) This circuit has the best picture quality I've been able to get from a 5200 and looks near flawless using s-video on a flat screen TV. Even though the board is larger than v2.0, it actually takes up less space. I also found a better spot to tap the audio signal, the top of R50 (shown in the picture.) It works in all Atari 5200 models and includes everything needed minus wire. It also works in some Atari 8bit computer models; I'm working on a compatibility list. I will begin listing them on ebay soon, or I can be contacted directly if anybody is interested. Price is $59 with video out jacks and shipping included. I also updated the v2.0 installation instructions to cover an alternate installation that doesn't require lifting the GTIA pins. a 8bit svid kit v2 install.rtf

I forgot to mention the GTIA pins don't need to be lifted, the kit can also be installed by removing the CD4050 and soldered to the correct points on the Atari circuit board. Also the 1k pull up resistors would need to be removed either from the Atari or the mod board. The color signal from GTIA pin 21 does not go to the CD4050, but instead to a transistor based amplifier. From pin 21 the signal passes through a 3.3k resistor and 10pf cap, so the first component would need to be removed for the wire going to the mod circuit. Later versions of my install instructions have this installation option covered. If the GTIA is not socketed or the owner prefers not to bend the GTIA pins this would be the best install option. The v2.2 kit I hope to have ready for sale by late June. It is untested in PAL machines, although it should work. Thanks to Ransom for the suggestion to plug the board into the GTIA socket, which became v2.2 Thanks for poobah for suggesting I use machine pins for the board connection. The screenshots I posted (in the Atari 5200 forum) are from an Atari 5200. I've heard the 1200XL has a noisy ground, which may effect picture quality. I'm not sure if there's a way to fix that. I'm working on a compatibility list for the version 2.2 kit. If anyone knows what Atari computer models DO NOT have a socketed GTIA I would appreciate the info. I think it's just some of the later XE models. The v2.2 PCB measures 2.4" wide by 2" high. The top of the board extends out 1-1/8" from the GTIA socket, so there cannot be any tall components in this area. I uploaded my latest v2.0 installation instructions. a 8bit svid kit v2 install.rtf

The Atari 5200 / 8bit s-video mod is discussed on this page with schematics. http://www.atariage.com/forums/topic/193474-better-atari-5200-s-video-mod/page__st__25 I've been building and selling these on ebay since April. This was originally an Atari 5200 s-video mod. Then I realized the Atari 8 bit computers have the same graphics chipset so it wouldn't be too difficult to make a version of the circuit that works on the computers as well. I looked up schematics of various Atari 8 bit computers and found the video modulation circuits varied quite a bit between different models. I just decided to build a complete video circuit so It would be simpler to write instructions for. It started out as a hybrid using portions of the Atari 800's circuit, the luma amp from the original 5200 s-video mod, and a FMS6400. It's been changed around a couple times and I think it's now a pretty good design. I also tested a circuit similar to Batari's Atari 2600 s-video mod, but that had vertical lines and several other odd issues so I won't be using that. I've made 2 different versions of the PCB, with a third in the works. v1.2 is for the Atari 5200 only v2.0 is for the Atari 8 bit computers and the 5200. It is wired to 6 lifted pins of the GTIA. v2.2 is in development and plugs into the GTIA socket (with pass through for the GTIA.) If anyone has any questions about the mod feel free to PM me.

Thanks! Just what I needed to know. I found some on ebay and have them on order. PM sent regarding the "reward" to solving my dilemma.

Some changes made to the North American NES were beneficial, like composite video out. That's the only good change from a gamer's view though. The rest of the changes only helped Nintendo. The addition of the NES10 lockout chip is what really made Nintendo successful during this period, combined with their third party licensing agreement meant they had exclusive rights on many games. It's why Atari and Sega never had a chance in the 8 bit generation. Maybe Nintendo never meant for the audio input pin to be used in games, just the Disc System. But leaving that pin unconnected while adding 10 pins that go to a unused expansion connector was just dumb. The ZIF socket was a really bad design choice, but that allowed Nintendo to "fix" the problem and sell cleaning kits. I guess 1985 was a better time to release a gray VCR with light gun and robot than just another video game system.

I'm working on a new Atari 5200 / 8bit computer s-video mod board, one that plugs into the original GTIA socket and has a pass through socket for the GTIA chip. I attached a picture showing the setup. It's functional, but doesn't exactly make a good connection. The problem I'm having is the header pins I got are too thick to plug into the original Atari chip's socket, and I had to tediously file them by hand. The chip's pins were .010", while the header pins are .025" thick. Is there something made for this purpose? It would need to be 40 pins .1" pitch .6" row spacing. I know they exist because I've seen them on the 8bit domain mod. I just have no clue where to get them. If anyone could tell me where to get such header pins for a 40DIP socket to PCB connection, I would greatly appreciate it, possible reward being one of the finished circuits maybe?

After looking for a cheap Atari 5200 compatible controller extension cable for some time, I finally found one. eBay seller gamedoctorhk is selling neo geo controller extension cables that have all the pins wired. They are 4 feet long and work great with my masterplay clones (should work with the trackball too.) I paid $13.99 with shipping. I still have parts and pc boards left, so I'm going to make another 8 masterplay clones for sale if anybody is interested.

I've only fixed one PS3 with YLOD, as opposed to probably 10 xboxes with RROD. I've had much better luck with longevity on the PS3 fix, but they'll still fail eventually. It all depends on if you get the chips hot enough, and using just the right amount of Arctic Silver thermal paste. I pre-heat the entire board so it's warm, but not hot, first. Then cover the components except the CPU and GPU with foil (I take a large sheet of foil and cut out small squares the size of the chips.) After heating the chips for a while on the low setting, I set the heat gun on high and get them pretty hot, but keep the heat gun moving so the heat isn't concentrated on one area. If you don't get the chips hot enough, the repair won't last. It takes practice. Then I let the board cool for a good 30 minutes without moving it. When you apply the thermal paste, use a very thin layer on the chips and heatsink surface. Note that each time a PS3 or XBOX is repaired, it will not last as long. If it's been fixed more than 2 times, the board is pretty much junk.

Many different PS3 models and bundles have been released since 2006, and many people complained about the pricing at launch. I'm not talking about that, but a certain bundle in particular has given me buyer's remorse ever since I bought it new. You see, when Metal Gear 4 was released as one of the first games to truly show off the PS3's capabilities, there were not one but two "special edition" consoles released. The first one was sold in retail. It had a 80GB hard drive, PS2 backward compatibility, 4 USB ports, memory card reader, and included a special edition copy of Metal Gear 4. It had the same shiny black/chrome look as the original 60GB PS3 and was priced at $499. That was the one I wish I bought. The other was sold by Konami directly through mail order. Supposedly, only 10,000 were made and it had a cool "gunmetal gray" color scheme. It also included a gunmetal gray controller and limited edition copy of Metal Gear 4 included. It also supposedly had a gray molded plastic case (as opposed to painted.) Unfortunately, it had only 2 USB ports, no PS2 compatibility, no memory card reader, and a measly 40GB hard drive. This particular turd was released in June 2008 available exclusively from Konami's website for a whopping $599. Yep, less features than the original 60GB PS3, released a year and a half later, at the same launch price. But it was cool looking gray! Only 10,000 made! A true collector's item! I admit I was a sucker looking for a valuable collectable, and I bought the damn thing. Konami had trouble selling the 10,000 they made. It was advertised as "extremely limited quantities" going fast! To add insult to injury, the price was lowered to $399 a mere 6 months later. Here I had an unopened system I hoped would slowly go up in value and suddenly it was now worth $200 less without even opening the box. Needless to say it was a true middle finger to Metal Gear fans. No, it gets worse. It had a painted on finish. There were spots where it wore off, revealing black plastic underneath. The "limited edition" game was simply the regular game in a larger box that included a making of DVD. I've seen people on ebay trying to sell unopened systems for $600 or more, and they never sell. WONDER WHY....

I lowered the prices if anybody is interested. The circuits include good documentation and (of course) work.

You'd probably have to make or modify a steering wheel controller to use with Pole Position. For steering, you would need a 1M pot between pins 9 (common) and 10 (horizontal.) The gas is pin 13 to ground, brake is pin 14 to ground. Then there's the shifting, which would normally be up and down on the controller. You could use a pot between pin 9 and 11, but that would be awkward. You could wire two SPDT switches with 500k and 10k resistors instead. I guess the short answer is it wouldn't be worth it for one game.

I designed these circuit boards for various modding purposes, some are assembled, some kits, some are just the pcb. All include instructions. All circuits require regulated 5v except the colecovision video amp. 1. Stereo amplifier 2W x2 great for PS3 or XBOX laptop project; nice sound headphone jack support digital volume control; remembers volume setting after power down Uses 4 or 8 ohm speakers built-in circuit for slowly pulsing "Apple" LED assembled with pinout 2 available - $29 ea 2. RGB helper RGB amplifier and Sync separator Useful for NES, Turbografx 16, N64, etc. Assembled or bare pcb assembled with pinout 2 available - $19 3. Atari 5200 v1.2 s-video mod pcb For info see this thread: http://www.atariage....00-s-video-mod/ Bare pcb w/ assembly and installation instructions including Digikey parts list. Lots available - $5 ea 4. Atari 5200 v2.0 s-video mod pcb For info see above thread Bare pcb w/ assembly and installation instructions including Digikey parts list. 10 available - $9 ea