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Macross_VF1

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About Macross_VF1

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  1. Thanks mate! I have the necessary photos and material to do a similar tutorial for a PAL light sixer if it is of interest.
  2. Since this forum has been quite helpful and provided a good amount of assistance to me (and will probably continue to do so in the future) I figured it was time to give something back. Hopefully someone will be able to benefit from this. Background This actually started with an Atari 5200 that I added to my collection. I figured I should do something about the video signal as I live in Sweden and old NTSC RF-signals just isn't very good or easy to tune into when you live in PAL territories. I settled on doing an S-video mod on my 5200, this particular one in fact and got a good result. A few months later, I added a PAL Atari 2600 'Vader' to my collection and I started looking into video mods for it as well. I found another S-video mod, the instructions can be found right here on Atari Age. What really struck me was the similarity between the two. However the instructions were not quite clear enough for my taste, as they really didn't seem to take into account PAL consoles, only NTSC. So I figured why not make my own tutorial. Now while this is aimed at the PAL Vader I would be highly surprised if some/potentially all other four switch Atari 2600 versions/revisions can’t use alot of the information I’ve provided. Why S-Video? Partially because I have invested in a Retrotink 2X and it’s a great little device for this sort of stuff. The other reason is cost; an S-Video mod is far cheaper than a RGB mod, probably just a tenth of the cost and I have several Atari 2600 consoles. Plus I really like the kind of mods where I can pretty much put together everything on my own. Schematic I’ve cobbled together a schematic using photoshop and various resources found on the net. I have no idea where I got the base schematic so I fully admit to being a filthy, dirty thief (credit goes to whoever made the first one). What I’ve hopefully done is make it easier to read and interpret. Before attempting this you should really read up on the instructions I linked to above as it covers the essentials. There are a few differences however, for instance I haven’t used quite the same order for the inputs and outputs from the CD4050 chip. However that shouldn’t matter as the chip has several unused pins already and any of them should work. Also, a quick note on the 4050, many Atari consoles have this chip inside so you could potentially use the outputs from it instead; however my Vader did not so I had to buy a brand new one. It’s not a strictly necessary component but the picture quality is improved by its’ inclusion. There are also references to resistors and capacitors in the original instructions, which are not particularly helpful, partially because the part numbers are hidden underneath the components on the circuit board and also the numbers seems to be different on PAL consoles. Finally, my one personal contribution to this schematic is the circled 6.8k resistor for the chroma signal. I highly recommend replacing it with a 10k trim pot. Not only were it used to great effect in the very similar 5200 S-video mod, but as I discovered when I did this exact same mod on a light sixer, a 6.8k resistor made the colours really faded. My Vader on the other hand was fine with a 6.8k resistor but having the ability to make fine adjustments is a nice and potentially necessary bonus. Unfortunately I was out of 10k trim pots when I did this mod. *grumbles* Installing the mod Once the circuit has been assembled it’s time to crack open the console. Turn it upside down and remove the four screws. Take note that the screws comes in pairs and are ever so slightly different from each other. I don’t think it really matters but better safe than sorry. Flip the case over again and remove the top. It can be a bit fiddly due to the protruding switches but it shouldn’t be too difficult. When the circuit board is free, the RF shield needs to be removed. There are several tabs around the shield that must be straightened out. I know there’s somewhat of an ongoing debate on what to do with RF shields. Some claim that it’s rather unnecessary in this day of digital devices and just throw it away. Others feel that the shield was put in for a reason and it should be left in place. Personally, I like to keep my consoles as original as possible and besides, RF shields are sometimes truly integral to a consoles design, providing protection against interference as well as odd ball purposes like acting as heatsinks and providing Ground. With the circuit board fully exposed, take note of the TIA chip in the middle, the marked point to the right and the trim pot to the left. The last one is important because the pot might have to be adjusted before everything is put back into place. Besides, it’s a common failure point, giving it a bit of TLC when the console is already open is not a bad idea. I’ve also, provided a better close up of the smaller circle. This is the point where C212, C213 and R214 all connect and the place where I picked up the Chroma signal. I’m not completely sure it’s the best place but it certainly worked out well enough for me. Now you could solder the wires directly to the top but personally I found it easier to flip the board and connect everything there. It also meant I could make a fairly small cut in the RF shield for the wires to pass through. I used some Velcro to fasten the mod circuit to the lower RF shield and a zip tie to keep the wires collected. On the back of the console I drilled the appropriate holes and installed the necessary connectors. You don’t actually need two RCA connectors, it’s not like the system provides Stereo but it’s nice to have. I also installed a molex micro-fit wire to wire connector on the output wires, visible between the plastic case and the circuit board. It’s not at all necessary to do so but it will be really handy if I ever have to open up the case and do further service. All that’s left now is decide what to do with the old RF cable and then put the top case back on. As stated earlier, I like to keep my consoles as close to original as possible and that includes the RF cable. However since it’s not needed and the plastic case have a lot of spare space I just left it disconnected inside the console. And the result? Well take a look! The signal has been routed through my Retrotink 2X and then into the TV. Not bad for something cobbled together by a blithering idiot. Closing words I fully expect some of the smarter/more knowledgeable of you to point out all my mistakes and what I could have done better. Heck, I invite you to do so, especially if it turns out I’ve made any terrible and potentially dangerous mistakes with the S-video circuit. However, I really hope this will at least provide some help to someone out there.
  3. When I looked at the RAM chips I realized they are the same as found in some other consoles, particularly the same as in my XEGS. Almost every chip is socketed in it so all I needed to do was desolder the chips in the Lynx and do a swap. The RAM worked flawlessly in the XEGS so that's apparently not the problem.
  4. I managed to find this thread and the problems described seem very similar to what I'm experiencing. I suppose I can try a recap and switch the ram chips with some fresh ones, it's easy and fairly cheap. If it's Suzy however, I'm pretty SOL, right?
  5. Just got an Atari Lynx I in the mail today. And while it does power on and I get to the title screen, I can't get to the actual game. Now I only have one game, Roadblasters, but that's not the problem as it works flawlessly on my Lynx II. So what basically happens is that I power on, I wait a second or two, get the boot/title screen but when the music is supposed to start or when I press an action button, I either get a black screen or the screen just freezes and nothing happens. In both cases I also get a constant screeching noises from the speaker and the only way to stop this is to shut off the unit. Things important to know: One capacitor, C36 has already been replaced as it was visibly leaking. I haven't done anything to the other caps. It's a rev 2 board. While the console was powered on, I put my finger on the RAM chips to feel if they got hot but they are nice and cool.
  6. I had forgotten about the color pot. Sure enough, as soon as I touched it, the colour started flickering like crazy. The solder joints didn't seem to be bad but I retouched them anyway. Also, while I don't have any electronics de-oxidizer spray at the moment, I figured I could use Isopropanol instead. Some twisting later and it seems to work as intended. Thanks for the help!
  7. The voltage regulator seems to output a steady 5V no matter if the console have been started cold or been powered on a few minutes. Even more strange is the fact that the flickering have stopped. I have done nothing else to the console, no changes, repairs or mods apart from the previously mentioned composite mod. It apparently just decided to behave itself.
  8. Thank you I can understand your point but you never know, I might do it in the future and also, I like to think ahead. I have a collection of around 190 computers and consoles (at the moment) and maintenance and repairs have become a necessary evil. Part of that includes ensuring that I (or possibly another, future owner) actually can use them in the future. Any unit that only feature RF out are particularly vulnerable since analog TVs and monitors are already somewhat scarce and will only become more so in the future. Other connection types have several good digitizing options available, I myself use both a Retrotink 2X and an OSSC, but RF out does not.
  9. I have a PAL Atari 2600 jr that I've just upgraded with this composite mod: https://www.console-corner.de/videomod.html. It's not the first time I've modded a 2600 with this particular mod, nor will it be the last and it has worked great so far. However this particular 2600 have an odd quirk, when it's powered on it flicker between black and white, a distorted colour set and the correct one. If I leave it on for a few minutes the flickering gradually stops until I only get the proper set of colours. This has nothing to do with the B/W switch, nor does it have to do with the mod as it also happens when using RF. Best I can tell, it quite frankly reacts as if the colour information from pin 9 on the TIA chip isn't correctly supplied. Is it something as simple as the capacitors needing replacement or do I have a more serious problem?
  10. Here's a bit of an oddball technical question. I've recently managed to acquire a 5200 at a pretty good price that was listed as powering up but no signal. I thought it was worth looking into and I'm glad I did as it actually works, though the picture over RF is pretty poor so I will mod it with S-Video and/or composite. I like to future proof my consoles and computers so they at least can output composite. However, it also lacked controllers and while this is not much of a concern to me, this particular unit is mostly just going to sit in my collection, I do want to see at least one game going past the start/title screen. If this were a 2600 or similar machine I could easily just short the appropriate controller input pins to produce the necessary 'button' press but the 5200 is of course different in this regard. So basically, which input pins needs to be 'connected' to produce the start and indeed any button press? I'm not terribly familiar with the grid layout of the buttons on the 5200 but if I'm reading the schematic correctly I think the start button should be activated with pin 7 and 4?
  11. So I've managed to snag myself a rather unusual old computer (at least over here in Sweden), a PAL TRS-80 Coco model 1. Now I'm wondering if there is any big differences between the PAL model and the far more common US version? Because if at all possible I want to give it a composite mod, something that seems to be rather easy to do just based on a simple google search, though I can't tell if the mods available will work without modification on a PAL computer.
  12. No matter, it's dead now. I tried reseating the socketed chips and I must have damaged at least one because it only shows a black screen. FML
  13. So I have an issue with my Philips Videopac G7400. It outputs a piss poor RF signal, no matter how much I try to tune the TV. When I started digging around the net I saw that it was easy to convert to RGB, just a matter of installing a number of components. https://www.the-nextlevel.com/odyssey2/articles/g7400guide/rgbmod.php Unfortunately, nothing improved. As can be seen in the attached image (the image was taken while using RGB), the signal is still distorted and it does not matter if it is RF, composite or RGB. Anyone have any idea what the problem might be? I have tested the internal AC adapter and it outputs pretty much the correct voltage, 4.95V on one line and 11.43V (should be 5 and 12V respectively) on another.
  14. Just managed to acquire a really old console; A Philips Odyssey 200. Unfortunately, it behaves strangely. The picture is warped and it does not seem to start as intended. As the first picture below shows, I get some strange results. I can manipulate the two darker icons with the controls but the game doesn't seem to start, the "ball" is missing and nothing really happens. And before anyone asks if it's the TV coulnd't tune into the right channel, what is shown is actually composite since I have connected an external composite circuit. When using RF the picture remain the same though obviously blurrier. What I primarily wonder about is whether this can be due to low voltage. The original battery holder is missing (second picture) but it's supposed to accommodate 6 C batteries for a total of 9V. Instead, a previous owner has soldered an external AC adaptor that can only handle 4.5V (is tested and gives 5V so well within tolerances) .
  15. The extra/external ground wire you are referring to is present on the 1531 but it has been fully integrated into the cable. It's called 'shelled wire' in the schematic.
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