Search the Community

Greetings, Atarians! I always enjoy a good "mod log" that shows someone's efforts in tweaking their console to be something BETTER, and so I thought I would share my 7800 project that I wrapped up a week ago. I personally find "mod logs" to be helpful inspiration or good instructions for my own projects. Some of you may be considering the mods that I used on this project, and so you can also look at this as a "mini-review" of these mods. I took a stock 7800 and made the following mods to it - - - The "European OS mod" supplied by BEST ELECTRONICS - Composite and S-Video mod board sold by our very own LittleJoe, and based on the Longhorn/batari board model - A "disconnect" switch and case mod to clean up video interference on the video mod - The simple compatibility mod with a switch for those 2600 carts that don't work in later revision 7800 models - A clean, new old-stock ATARI 7800 metal case label The Base Unit I started with a basic 7800 that had the solder points and hole in the side of the case for the expansion port, but no expansion port . . . The European OS mod from BEST ELECTRONICS Best Electronics in California sells a "kit" that you can use to modify your 7800 to use the European version of the 7800's operating system http://www.best-elec...m/7800.htm#euro Highlights and advantages of that mod include - - - No logo boot screen; goes right to the inserted game without delay - Built-in ASTEROIDS game when there is no cartridge inserted It's a relatively complex mod, requiring the removal of the current OS chip, which is soldered directly to the board, replacement with the new European OS, and then a tricky "piggyback" procedure with another integrated circuit where you basically solder a chip provided in the chip onto ANOTHER chip on the board. If you are comfortable with soldering, it's all straightforward, just time consuming. They even provide nice "extras" like shorter case screws to use when you re-assemble your console, which helps prevent breaking the plastic case - - some older 7800s can have brittle plastic, and if you overtighten, or sink the screw too deep, you can crack the threads or case! Here's the instructions that came with the kit, if you want to peruse the step-by-step and see if you want to tackle it! BEST ELECTRONICS 7800 Euro OS Mod Installation Instructions.pdf And, here's the highlight shots of the process - - Last glimpse of the original board before it underwent the knife Original OS chip desoldered (note that I keep flipping the motherboard around while I work on it, and so you will see the placement of components jump left and right in the pictures!) New IC socket in place, and new Euro OS chip inserted The "piggyback" IC completed (first picture) and the 30-gauge Kynar wire jumper that goes THROUGH the board and runs to another chip in place (second picture). The NEW socket to the left is for the video mod, which is coming up after this section! And those were some of the highlights minus a few other steps! When you fire it up, ASTEROIDS for the 7800 pops up right away! It REALLY is a straightforward mod. BEST ELECTRONICS' instructions are very detailed and thorough. Again, check out the attached PDF where you can preview the details of the work. I really like not having to wait for the "splash screen" while games are booting, and the added plus of the built-in ASTEROIDS games is fun! I was curious about PAL games on this unit, since now it would seemingly be "PAL-compatible" with a Euro mod, AND not have copy protection on it, which was a feature that was left out of the PAL models. PAL copies of some 7800 games are some less expensive, too! Someone here on AtariAge had that same question, too - - http://www.atariage....cs-euro-os-mod/ SO, I asked Bradley over at BEST ELECTRONICS to see what they knew. This is what he replied with - - "Q. As you well know, the NTSC 7800 has a region lockout for PAL games. With the European mod in place on an NTSC unit, does that mean I can then successfully use PAL cartridges? A. Good Atari question. Never been asked that Atari question before. I had to check our Atari 27+ Atari Super Tech to get you an answer. He said that most Atari 7800 PAL games will run on the 7800 with the Best Composite Video mod with the Euro OS upgrade installed. But some 7800 made PAL games with Text at the bottom of the screen was hard to see (because of the 50/60 Hz screen display differences). The Atari PAL 7800 games our Atari Super tech had, Choplifter, Basketbrawl and Sentinel did have video blanking problems and were not playable. A couple more played fine but had sound problems. All of the other Atari 7800 PAL games tested fine with full sound and normal color (normally on a NTSC console with PAL games you will get a black and white display) with no normal 50Hz (played on a NTSC 7800) video rolling screen." Interesting! I have not personally tried it yet, however - - I was bidding on a PAL lot last month, but the pricing got out of hand, and I backed out, and have not pursued any other PAL carts since then. I will likely get around to it here someday! I don't know about 2600 PAL games - - I would assume they will roll, since the 2600 component of the 7800 is separate, and not PAL! Also, I have not YET run into any compatibility issues with 7800 games on the Euro OS, but I'll update this thread if I do! So, there you go! I give the Euro OS mod "two thumbs up" and would recommend it highly! LittleJoe Video Mod based on Longhorn/batari Model Now with that done, it was time to move onto the video mod. Our very own AtariAge user "LittleJoe" is selling some excellent 7800 and 2600 video mod boards based on the classic Longhorn/batari design His website - - http://www.electroni...entalities.com/ He's a great guy to deal with, and really goes out of his way to help you out if you need it! I had some (self-created) issues with my 7800 board initially, and he was super-friendly and fixed everything up for me! The video mod board is really handy - - it is made to just socket right into the 7800 motherboard after you remove the IC that is there and put in a socket, which is provided in the 'kit". Here's the NEW socket in place, ready to accept the video mod board - - Here was my problem, though - - see that chip to the right of the socket? That's used with the European OS mod for the "piggyback stack" and once that second chip is in place . . . it's too high to socket the nice 7800 video mod board in like it should be! My first solution was to stack a SECOND chip socket on the first one . . . TO make a long story short, that solution and a few others I tried didn't work, and finally somewhere during my modding process, the 7800 video mod board stopped working correctly! Basically, I lost the video output, and was only getting sound. I contacted LittleJoe, and he kindly offered to look at BOTH my board AND the video mod board. A few weeks later, he sent it all back, and had made a 7800 video mod board with LONGER pins and a secondary socket so I could socket it right into the board with no interference to the Euro OS mod! Perfect! Some jacks installed on the side of the 7800 case, and I was ALMOST ready to go . . . (Note: I didn't show it here, but I always epoxy in the backs of my audio/video jacks to make them rock-solid and prevent backing out. I highly recommend it!) I say ALMOST because there was a bit of a video issue that the perfectionist in me wanted to clean up . . . ! Add-on Disconnect Switch for TIA 9 on the 2600 Circuit of the 7800 Video Mod Turns out the TIA 9 line causes some interference to the 7800 when it is running in 7800 mode, and the best way to deal with it right now is to just turn off/disconnect the TIA 9 line while you are running in 7800 mode (it was discussed here: http://www.atariage....s-on-video-mod/). The video mod board actually switches "off" the TIA 9 automatically, but the automatic switch is a little "leaky" and the interference still comes through. NOTE - - this interference is the sort of thing that only a video and audio FREAK like me is really going to notice! It's only slightly visible on pure black screens, and I feel you have to be looking for it. This "additional" mod is purely optional, but I like to do things 100%, so I went for it! I think that LittleJoe's video mod is EXCELLENT in it's current form, and this to me isn't a negative in any way! It's just the way it is out here in the wild-west of vintage gaming mods . . . ! So, the TIA 9 input is where the blue wire coming off the LOWER LEFT of the board is in this picture - - Usually you just wire this point directly to TIA 9, but what you need to do for this mod is put a SPST (single pole, single throw) switch along that line, and flip it to "disconnect" when you are getting your 7800 mode on. Easy! Finding the right switch, however was a bit more challenging. I settled on a classic RADIO SHACK SPST "soft touch" in black and red, which I thought matched the classic stylings of the 7800 - - Pop a hole in the case - - Wire it up (I used some heat-shrink tubing to cover and clean up my spliced and soldered wires) - - I put the switch right under the "lip" of the 7800, where it has easy access, but doesn't visually affect the look of the console at first-glance - - Console flipped upside down to you can see how well the plastic matches - - And, of course . . . LABELS . . . ! I guess secretly I want to be Captain Picard, as I appear to have used the word "ENGAGE" . . . a subliminal slip? One last mod before we button up the case . . . Compatibility Mod for Certain 2600 Games on 7800 Console It's been covered before in detail many times here on AtariAge, but basically some 2600 games will not function on later revision 7800 units because of a motherboard change that ATARI made . . . in order to accommodate a 2600 cartridge . . . ! They were apparently trying to make the 2600 version of DARK CHAMBERS compatible with the 7800, and broke things for other games along the way. The simple solution is to disconnect a resistor on the board, and then if you want, put a switch on it . . . so you can restore compatibility for ONE 2600 game . . . I know, overkill, right? Well, I wasn't using the CHANNEL SELECT switch anymore (yeah, S-Video!) and so I decided to use that as my switch. First, disconnecting the single necessary resistor and solder a wire to it (it's the BLUE wire in this picture; the others are for the 7800 video mod and Euro OS mod) - - Add some heat shrink tubing for cleanliness and short protection - - The handy, already-installed switch for use - - You need to disconnect the switch from the ground plate of the motherboard in order to use it, so cut traces on the bottom and top (bottom is only shown here) - - Good to go! Yes, overkill, but hey, we're shooting for 100% Finishing Touches So, with all that done, we can close up the case and . . . oh, wow, that metal label looks horrible and scratched! No worries, BEST ELECTRONICS to the rescue again, with a FRESH old-stock metal label for application! First, you of course need to tear it off, and remove the old adhesive - - A bit laborious, but the final result looks GREAT! I'll take that protective plastic film off the metal label someday . . . maybe . . . WELL, that's it! I hope you have enjoyed it, or have gotten a few ideas from it. I don't really feel this is done 100% - - I need to "fix" the cartridge slot so that there is not the issue with 2600 cartridges fitting too tightly. I was hesitant to cut up the cartridge connector at this time, though, so I will save it for another day . . . or build or obtain a "cartridge extender!" Thanks for reading! -atari2atari