Atari 400 Questions / Help

[Binarygeek]

Hi folks

 

I recently acquired an Atari 400 computer and I may need some help. I have never used one of these and I'm not sure how they work. I may or may not have an issue and am turning to the Atari guru forum to set me straight. Question / issue:

 

With a 16K card installed, I insert a couple of cartridges (Basic, Pac-Man and Star Raiders) and the cartridges do not start, but instead go to the Memo Pad. I swap out the CPU and RAM boards several times and same thing. I then insert a 32K memory card and same thing. The keyboard works fully and all RAM and CPU boards work and are SALT- tested in an 800 computer. Finally I insert another 32K card (Mosaic) and the cartridges start. WTF?

 

Well, with 16K installed should the cartridges start on power-up? If not, how do I start them? I do have a schematic, but it is so blurry that it is virtually useless. If anybody has any answers /tips with this, I would appreciate some help. Thanks!

 

Rick

[tjlazer]

Yes if they are 800/XL carts they should work with 16k

[SoundGammon]

If the memo pad is working, ram is working!

 

Sounds like a dirty or bad cartridge connector.

[Binarygeek]

OK, the 400 is not working properly with a 16K card. Have cleaned cartridge, memory and CPU board connectors. Used a paper towel with alcohol, and then inserted cartridge with the paper towel to make sure connectors are clean. What I could really use right now are a set of (readable) schematics for the 400 or any ideas.. Anybody know if or where a set of these may reside? Thanks.

[+orpheuswaking]

Try this first. Pull the unit apart and remove the cart guide. Then plug star raiders in and turn it on. I've found that over time the cart socket gets worn to the point the cart guide causes the cart to fail contact. (You will have to manually open the cart door obviously)