View Full Version : Atari 400 questions

June 3rd, 2011, 05:47 AM
Hi! Please help me for atari 400.

What type TV connector have atari? Composite or antenna video out? Because my atari 400 dont show anything when i connect it to composite "in" on TV

And if i dont have a cartridge, can i will something to see on the screen?

June 3rd, 2011, 08:00 AM
While I don't have a 400 myself, I've heard it only comes with antenna (RF) output, at least the earliest models. If yours is a PAL unit, it probably tunes in around UHF 36. Furthermore I'm unsure if you get built-in diagnostics or nothing without a cartridge, I think you're supposed to get diagnostics?

June 3rd, 2011, 08:21 AM
Actually, if I recall correctly with no cartridge you'll get that useless "memo pad" program, same as an Atari 800. Its good for checking if your keyboard works and little else.

June 3rd, 2011, 08:59 AM
I recall it being RF also, usually you can tell in that the plug is sort of maroon or brown color. Ditto also on the memo pad (though that was from reading to double check). Unfortunately it doesn't have basic built-in to the rom like most of the other systems. It should come up and say something like "ATARI COMPUTER - MEMO PAD" with a blue background screen.

June 3rd, 2011, 09:04 AM

I know when electronic have antenna block, then in circuit board we must have some metal box near video output.
Some metal box present here... My atari 400 from USA, then it have NTSC video signal..
When i connect atari to composite TV "in", TV sad "no signal"
Antenna connector in my TV not suitable for atari... Ok i will try make adapter for my TV antenna connector

cartridges expected a few days...

June 3rd, 2011, 09:32 AM
That is correct, early home computers and video games from the USA tend to have antenna output in a phono (RCA) jack. The lead would usually connect to a TV/game switch box in which you can attach aerial antenna and then there were leads to connect it to a TV set, either 300 ohm or through a 75 ohm balun with F jack. What you need though is a phono to BNC (KX ?) or whatever the 75 ohm antenna connector is known as. I have an Ultra PONG that connects in the same way, but my home made female RCA to antenna cable results in a very poor image. I'll probably try a smaller adapter if I can find one cheap.

June 3rd, 2011, 09:53 AM
The lead would usually connect to a TV/game switch box in which you can attach aerial antenna and then there were leads to connect it to a TV set, either 300 ohm or through a 75 ohm balun with F jack.
I know what you mean. I see this TV/game switch boxes but i don't have it...

I think i can will connect antenna without any resistors 75 or 300 ohm. Or resistors must be necessarily?

Dave Farquhar
June 3rd, 2011, 11:40 AM
I've connected a 400 to a TV with just an RCA video cable and an adapter that had an F jack on one end and an RCA jack on the other. I tried soldering one together myself with parts and got a low quality display, but with a commercial adapter, the picture was clear. In the States, the adapter costs about $5 at Radio Shack.

I don't know what the international shipping on one would be, but Amazon has an appropriate adapter here:

June 3rd, 2011, 12:27 PM
I can get an appropriate adapter on eBay for 2.95 - 3.49 including shipping.


Notice these adapters would be for European TV's, not the F jack used overseas.

June 4th, 2011, 08:19 AM
Thank you all for help! Today i was bay antenna connector and connect atari to TV
Me have something this on screen^


And i have two new questions

Atari power supply have 31VA this is 3.4 Ampere? (31 / 9 volts)
Atari 400 with 1 joystick, can work from 1 Ampere power supply? Because original power must be connect to 110 volts, in my country we have 220 and i must use power converter... too many wires here :)

And second question - joystick. Can i use joysticks from commodore64 or nintendo NES or sega in atari 400?

June 4th, 2011, 10:20 AM
And second question - joystick. Can i use joysticks from commodore64 or nintendo NES or sega in atari 400?

Commodore 64 compatible joysticks should work fine. (Commodore copied the Atari pinout.)

June 5th, 2011, 03:51 AM
According to the Atari 8-bit FAQ, the absolute minimum power supply for an NTSC Atari 400 is 9VAC 1.7A. Thus a 9VAC 1A supply won't be sufficient.

http://www.faqs.org/faqs/atari-8-bit/faq/ (scroll down to section 6.7)

June 12th, 2011, 11:24 PM
carlsson u really have the knowledge thanks for sharing such a helpful material .............

June 15th, 2011, 09:47 AM
thanks you so much for post)

June 17th, 2011, 10:10 AM
Here's an interesting use for the built-in memo pad:

I acquired my first Atari 8-bit system (an Atari 400, a couple power supplies, basic cartridge, some disks, but no disk drive) a few weeks ago on the local freecycle list. I was clueless how to get the video from the device to show on a modern TV, and hadn't done proper research. Then I had to put it aside for a bit.

A fellow in my town hosts an annual Atari Party (http://www.newbreedsoftware.com/atariparty/2011/). At the show there were several stations set up with lots of adults and kids playing and experimenting with the machines. It sounded like an arcade from the early '80s. Fantastic! So I brought my newly acquired Atari 400 to the show to see if anyone could help me evaluate whether it works or not. I happened upon one station where a fellow had his 400, 800, and 1200xl set up. I asked him if we could diagnose my 400, power supplies, etc, and he immediately indicated to me that he was completely deaf. We communicated quite effectively by taking turns typing on the keyboard into memo pad. I learned that my 400 is completely functional, the basic cartridge works, both power supplies work, and the floppies are all readable. He also showed me the proper connections to connect it to the TV using the game/tv switch in my kit.

Then later on there were several raffles. Each attendee was given two raffle tickets and allowed to submit them any of the raffles. I submitted both my tickets to the Atari 800 raffle, and I won it! It's a very nice Atari 800 kit (incl disk drive, basic cartridge, USB downloading cartridge and flash cartridge, several books, power supplies.)

I'm set for a while on Atari stuff. I don't have a whole lot of cartridges, but I'm more interested in the hacking and programming aspects anyway.


July 5th, 2011, 11:26 PM
Few days ago cartridges comes! But not what I bought!
As a result, the seller gave money back. But it does not please me so much, only one cartridge work :(
I would ask, can I burn in the other chips some games to atari 400, put this chips to cartridge, and all this will be work?
If yes, what EPROM chips be good to atari 400 cartridge?