Six Switch Repair Issues

[RWDPLZ]

Hello! I'm working on a couple Atari 2600 six switch consoles, a heavy sixer and an early light sixer, both made in Sunnyvale.

 

-The heavy sixer plays Donkey Kong and Dig Dug flawlessly. However, it will not play any of my other older cartridges (Adventure, Space Invaders, Pacman, ET, etc.). I tried cleaning the cartridge connector on the board and took apart a Space Invaders and cleaned it, and tried inserting it without the cartridge housing, no improvement. It either displays a black screen or a gray one with vertical lines and interference. Tried two different TV's, same results. Tried taking apart a Space Invaders, inserted the bare board fully to rule out the board not being fully inserted/seated, no change.

 

-The light sixer: When I turn it on I can frequently see the start screen of some games for half a second, but then shows interference, too. Donkey Kong is playable, but the screen is gray with white characters and the sound is a screeching noise (see image)

 

Tried Console5 refresh kits, swapping the 3 socketed chips between boards, replaced the 3 chip sockets on the heavy sixer, replaced the ribbon cables between the main and switch boards, deoxit-ed the switches and checked with multimeter, swapped switch boards between the units, replaced RF module on light sixer, tried a brand new and old power supplies. Both voltage regulators are putting out ~5.05 volts on the switch boards.

 

Any ideas? Thanks!

[RWDPLZ]

Well I fixed the light sixer: Short version is, it turns out it's a PAL unit. I bought it from a US seller that had advertised it as simply broken. It now plays NTSC games, just with a completely wrong color palette.

 

 

(ignore the 82/22 date code CPU, I was testing the one from a 4 switch). I also AV modded it.

 

Ever seen Dig Dug like THIS?

 

 

I found an interesting explanation of the color swaps here:

 

http://spiceware.org/atari_ntsc_pal_secam.html

 

For example, the sky above should be blue, but is displaying purple, as seen in the TIA color charts

 

http://www.qotile.net/minidig/docs/tia_color.html

 

It's made in Sunnyvale. The lack of any FCC compliance labeling probably should have been a clue?

 

 

 

Also bought and fixed a 4 switch Vader, with what turned out to be a bad CPU. Re-capping and AV modding next. Then hopefully the heavy sixer.

[RWDPLZ]

Heavy sixer has been repaired! I started swapping chips 1 by 1 with the Vader, and it turned out to be the RIOT chip. It now plays everything I throw at it. Original chip was MOS branded, date code 1577 (15th week of 1977), so almost certainly the original.

 

I've ordered replacement chips for the Vader and a Console5 kit to get it back to 100%

[Jason_Atari]

Every PAL 6 Switch 2600 I've seen has a P after the model number (see pic) You sure it's not just the colour pot needing adjustment?

[RWDPLZ]

Yes, I tried turning the pot to get at least a better palette, but ultimately left it there so it could potentially play PAL games with the correct colors if I get a TV that can somehow handle a 50Hz signal on 120V/60Hz. If you look at the TIA, the part number on the chip, C011903-11, is the PAL TIA, this one from the 30th week of 1978. You can see in this post the NTSC and PAL TIA's have a slightly different pinout, which was why swapping them between the NTSC and PAL consoles had no effect on fixing them.