Atari 800 - no sign of life

[TheDash]

Hi. Hope this is posted in correct place.

 

I have an Atari 800, been stored away for years in a safe dry place. I've just tried powering it up - using the power supply that came with it - and no sign of life .. no LED's even. I've tested the supply with a multimeter and it seems good, and I've tried another psu of the same spec. Is there a trouble shooting guide at all for the Atari 800? I've searched and can only find bits and pieces, or would anyone know of common or typical problems that I could try before I do the stupid thing and open it up and start messing?

 

Thanks for anything!

[Paul Westphal]

Open it up and start messing around. A card could be out of it's place.

Edited March 21, 2018 by Paul Westphal

[TheDash]

Yeah that's what I'm doing, right now I knew the RAM and OS was on a cartridge, but didn't realise the CPU was too! Pretty cool - I like it. Good modular approach for upgrading/updating pretty much everything.

 

But sadly no joy yet .. no LED when switched on. I'm thinking the next move might be reflowing a whole load of solder, unless anyone can suggest something else?

[Kyle22]

Is the top cover firmly in the closed position?

[TheDash]

Is the top cover firmly in the closed position?

No, it wasn't, but I see what you mean. I was wondering what that morse code like switch was inside - it's a power switch!

 

Sadly - still no LED. But thanks for pointing that one out.

[TheDash]

Ok - silly me. The procedure is - morse code like switch down (i.e. lid down), and then power on. LED's are red!

 

Thanks everyone for the pointers.

[+mytek]

No photo then it didn't happen .

[TheDash]

No photo then it didn't happen .

 

Sorry - didn't think! Bit rude hey?

 

Here's the beast -

[TheDash]

Here's the CPU cartridge / module

 

 

 

And something hidden away, deep inside .. note the 'W' Warner Bros logo on the left

 

 

 

.. and the now 'not so mysterious' Morse Code transmitter

 

[+mytek]

Wow still has the original plastic enclosed modules. This must be from around 1980-81?

[TheDash]

The plunger that pushes this switch down

 

 

 

.. pushed down normally by the lid

 

 

So push that switch down, put Donkey Kong cartridge in, and bingo. One nicely working Atari 800!

 

[Rybags]

If there's no signs of life then the place to start would be the PS board - you should be able to test the various outputs. +12V goes to the SIO plug and also I believe used for colour generation. +5V the most common, used by most of the system. -5V used by the old type of RAM that 400/800 came with.

 

Note of course you need both power switches engaged, so will need to clamp the cartridge door switch shut with something.

 

ed - OK, so it's a worker... grab these in case you need to do diags in future.

 

800.zip

Edited March 21, 2018 by Rybags

[+mytek]

Nice to see you got it working .

 

And thanks for posting the great looking photos.

[TheDash]

Wow still has the original plastic enclosed modules. This must be from around 1980-81?

I think this particular one was bought in 1980 - but internally it says Copyright 1979 - or just 79 in some places.

 

Thats a good couple of years before the Commodore 64. Shame Atari didnt get the slicker and much smaller form factor right earlier on, 800xl style. This Atari 800 is bulky and weighs a ton! Or 4 kilos to be exact.

[+Nezgar]

Old enough to still have shells on the ROM/RAM but not so old as to have a CTIA. I see NTSC GTIA C014889. I guess it still could have been easily upgraded afterwards since it's socketed.

[+Stephen]

Old enough to still have shells on the ROM/RAM but not so old as to have a CTIA. I see NTSC GTIA C014889. I guess it still could have been easily upgraded afterwards since it's socketed.

That was going to be my question.

[ivop]

I think this particular one was bought in 1980 - but internally it says Copyright 1979 - or just 79 in some places.

 

Thats a good couple of years before the Commodore 64. Shame Atari didnt get the slicker and much smaller form factor right earlier on, 800xl style. This Atari 800 is bulky and weighs a ton! Or 4 kilos to be exact.

 

I listened to a podcast once where a former Atari employee explained how they religiously followed all the FCC requirements regarding shielding and radiation. Apple and Commodore just did whatever they wanted and ignored the FCC.

[Sugarland]

The head of a q-tip will jam that switch closed well and requires no soldering.

[+Stephen]

 

I listened to a podcast once where a former Atari employee explained how they religiously followed all the FCC requirements regarding shielding and radiation. Apple and Commodore just did whatever they wanted and ignored the FCC.

Not exactly. Atari had no choice but to follow the FCC requirements else they would not be licensed to sell the product. Apple did not have a built in RF modulator, so was classified differently. By the time Commodore came around with the VIC-20 & C-64, the FCC regulations had been seriously relaxed.

 

That really sucked, because things may have played out quite a bit differently had the 800 had easily accessible expansion slots from the outset.

[shoestring]

 

I listened to a podcast once where a former Atari employee explained how they religiously followed all the FCC requirements regarding shielding and radiation. Apple and Commodore just did whatever they wanted and ignored the FCC.

 

 

 

[+Stephen]

*** Deleted

[TheDash]

 

I listened to a podcast once where a former Atari employee explained how they religiously followed all the FCC requirements regarding shielding and radiation. Apple and Commodore just did whatever they wanted and ignored the FCC.

I heard something similar - or that they were threatened with trouble if they did not over shield the thing .. something like that. So the response was some engineer designing that huge metal block that we see inside the 800, and which probably accounts for about 1/3 of the total weight! Yes Commodores shielding was thin - or even just silver card - but it seems like the reason has been explained here already.

 

I guess Atari were paying the price for being at the cutting edge, and regulatory response to the 'unknown effects of having a computer in your house, especially near children or the elderly' was OTT!

[Rybags]

C= were just being cheap.

 

But you have to wonder, what difference if any does a 2mm thick cast zinc-alloy Faraday cage have with an alfoil coated piece of cardboard if they're covering the same set of components and have the same airgap between adjoining pieces. Probably little to none.

[+kheller2]

I think this particular one was bought in 1980 - but internally it says Copyright 1979 - or just 79 in some places.

 

Thats a good couple of years before the Commodore 64. Shame Atari didnt get the slicker and much smaller form factor right earlier on, 800xl style. This Atari 800 is bulky and weighs a ton! Or 4 kilos to be exact.

 

Most of those Atari chips are marked mid 1981. So possibly Fall 81, Winter 82.

[Mclaneinc]

Glad to see you got it going...Now enjoy yourself

 

Paul...