pags35

Desiv is on the right track with the resistor. In order to balance out the TIA and Pokey you need to drop the volume on the TIA with a resistor. I don't know what the exact value would be because I don't have any pokey games but some people have said around 10k seems to work. You could always try using a 20k pot and adjusting it to what sounds best for you.

I have some composite video mod kits for sale on ebay: (I update the item # every month so click eBay link to see if they are available) eBay Auction -- Item Number: 290469005426 I designed and built them myself, although I am sure many others have taken the same approach of using the on board composite video after you remove the audio from the signal. These will work for any Atari 2600 or 7800 model. They are easy to install and the step by step guides are available as well. While the composite mod won't give you as good a picture as s-video, it is certainly an improvement over the built in RF. I am selling them for $25 with free shipping!

Do you have a voltmeter of some kind? The voltage regulator is the black chip on the lower left hand side of the board with three pins and a screw in it. the top pin should be about 9v, the middle pin is ground (0 volts), and the bottom pin should be about 5 volts. You read the voltage by using the two test clips on the voltmeter. Make sure it is set for DC voltage. Put the black test clip to the Ground (0 volts), I usually use the Rf modulator case. Then put the red test clip to the top and bottom pin of the regulator to test each of them and see if you get the proper reading for both of them. I would also do the same with the power switch and jack. same thing, black test clip to Ground and red to the switch/jack, see if you are getting 9v for that as well.

I'm not sure what you are using to hook it up either. Is it directly to a TV (LCD or CRT) or through a VCR. I am just wondering if you can be more descriptive. Do you still get the snowy "white noise" picture or is the screen all black or colored? Also as suggested test the voltage regulator and pin 3 of the RF Modulator for power. The board really does look like it is in pretty good shape so if I had to guess I doubt corrosion really is the problem.

I have done this with a number of Jr's that had bad IC's and it worked great. Like A.J. said just be careful when removing the old IC that you don't damage the circuit tracks. I think I also cut the IC off first so I could remove the pins individually and not cause any damage. I recommend using the individual pins that snap off to whatever length you want them for the socket. Good luck.

Yea that works. It is usually better to use those for testing and then when you get a good picture measure the resistance and replace them with resistors when you build the circuit, but they will work fine.

Sounds like a problem of something overheating, but since you already checked the regulator before and after the problem and replaced the caps you are running out of parts on the switchboard. You might want to check the RF modulator. Check the pins before and after the problem and see if they change. Pin 1 should be ground, Pin 2 the output, Pin 3 +5v, and Pin 4 the input signal(mine reads around 3.5v) . Pin 5 is usually the channel select switch if you had one. Also check for continuity between the pins and see if there is a short somewhere. Good luck.

Correct, it goes to the ground of the RCA jack and then needs to be connected into the ground on the Atari motherboard.

That is part of the problem with Ben's original mod. It works well for portables and crts but newer LCDs will either give you no picture or something less than desirable. Going through a VCR's inputs might work better if you want to test it out. I think he has an updated video mod that includes a simple transistor amplifier to boost the signal. http://benheck.com/book/support/Atari2600VidMod.htm I haven't tried the updated one as I take a different approach with my mods because I found Ben's original mod gave me a crappy picture on my LCD. I do use a transistor amplifier and it gives a good picture so that probably should help.

I think this would probably be your best bet for 3 different systems, a 3 way isolation switch. Then I would get RCA to coaxial adapters to connect them. These should work much better then hooking up all of the switch boxes which will almost certainly degrade the quality of the picture.

Your best bet is to get a copy of the Atari 2600 Field Service Manual to try and diagnose the problem or give us some more information. It is difficult without pictures and being able to actually run test on the system. But the manual is pretty helpful if you take a look at it and have a basic multimeter for testing.

I do have extra ones if you want to pm me. However if you have some power adapters that are not working I wonder if the problem is the female power jack on your system. Any chance you have another atari to test them out on?