Finding this was lucky - Atari 800

[rubber_jonnie]

@rubber_jonnie

https://images.app.goo.gl/CgL2kYumctNRT14B6

JD

Spot on, thanks.

[rubber_jonnie]

OK, so today is the day for the 800 to get a Stereo upgrade. This one is Acid Stereo from Lotharek.

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Note that in the 800 the long red jumper won't fit, it clashes with the cartridge slots, however in order to enable stereo this needs to go. This disconnects A4 from GND so that needs to be connected to A4 elsewhere.

It can come from pin 13 of the CPU, but I'll look for somewhere closer.

With the Faraday cage lifted off, it's a case of removing the POKEY, luckily mine was socketed, and fitting the POKEY to the Acid Stereo upgrade, then plugging back into the PCB.

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I do still have the jumper on here, but that'll be going in the next phase. Even with this tower of POKEY the faraday cage fits just fine:

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Next up I need to locate a source for A4 and get it connected, followed by the stereo out wiring and routing. That's coming a bit later today. So far it's been quite an easy install.

[rubber_jonnie]

And part 2 of the upgrade after a coffee and little cake :) First off I realise that the Acid Stereo had a socket fitted to it, so I pulled that off to reduce overall height,

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And yes, that pin is supposed to be missing, it mentions it in the install guide.

In the end I opted to pick A4 off the CPU, it's the blue wire coming from the CPU board here, the other 2 wires being for the Incognito Gold upgrade.

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Final install looks something like this:

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I then fed the stereo cable across the board to the front right corner of the Faraday cage:

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The reason being is that the Faraday cage has a slight gap here where the cable can be pinched when the screws are tightened:

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I pushed the cable back in a little for strain relief before tightening the screw. After that I was able to fit the rest of the Faraday cage screws.

I then fed the cable round under the PSU and into the strain relief that was originally intended for the RF cable:

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I then buttoned it all up:

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And then a quick test with Yoomp!

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Of this is a good test as it tests both stereo and th Incognito Gold at the same time so I know I didn't break anything during the upgrade :)

It's a nice simple stereo upgrade thats for sure and does offer other things too. I can recommend as in something like an XL or XE it'll be very simple to do.

[HigashiJun]

Nice and neat !

[rubber_jonnie]

Nice and neat !

Thank you sir :)

[rubber_jonnie]

OK, so I decided I wasn't keen on the flying leads for the Acid Stereo upgrade, so I've added this instead:

IMG20260327162427.jpg

It's much neater and is also 100% reversible :)

Also the phono plug connectors as I had it were really low quality so I wanted something a bit better and more hard wearing.