exxos's Atari, Amiga & retro forum

PhilC wrote: 09 Mar 2026 15:32 Slowly restarting the long list of retro tasks I have.

This made its way to the top today thanks to the last couple of chips arriving.

PXL_20260309_152443400.MP.jpg

The plan will be to take a couple of parts out of my working 800 and then carry out the pokeymax installation on this motherboard. Then if everything goes okay, I'll put the Incognito into this one and then rebuild it into the 800 case. I'll then keep the original working motherboard as a good spare for the 800.

mrbombermillzy wrote: 09 Mar 2026 16:10 Hang on a minute @PhilC ...

Werent you giving away BBC Micro cases a while back? :lol:

rubber_jonnie wrote: 09 Mar 2026 16:18

PhilC wrote: 09 Mar 2026 15:32 Slowly restarting the long list of retro tasks I have.

This made its way to the top today thanks to the last couple of chips arriving.

PXL_20260309_152443400.MP.jpg

The plan will be to take a couple of parts out of my working 800 and then carry out the pokeymax installation on this motherboard. Then if everything goes okay, I'll put the Incognito into this one and then rebuild it into the 800 case. I'll then keep the original working motherboard as a good spare for the 800.

One word of warning with the RAM & ROM modules for the 800. Atari had quite a few issues with overheating and in the end removed the cases from those modules to fix it.

That reminds me, I need to do my Acid Stereo upgrade to my own 800, trouble is somebody gave me an Acorn Atom replica to build and thats taking all of my time at the moment!!!

Might have to park the Atom for a bit as it's driving me batty ATM.

Also considering feeding the AcidStereo output to the video connector on the side of the 800 rather than using a cable out the back, will be a lot neater.

PhilC wrote: 09 Mar 2026 16:25
Actually that's quite a good idea for the audio, I'll probably look in to it. And I'm sure you'll work out the Atom soon enough, you are very near to it being fully working.

rubber_jonnie wrote: 12 Mar 2026 13:55

PhilC wrote: 09 Mar 2026 16:25
Actually that's quite a good idea for the audio, I'll probably look in to it. And I'm sure you'll work out the Atom soon enough, you are very near to it being fully working.

So I've been looking at the possibility of feeding stereo through the video jack of the 800 and it's not ideal.

The sound from the 800 is via pin 3 of the DIN connector. Checking several 5 pin din to phono (Composite+Audio) cables I have, the left/right audio channels are both connected together for mono sound and that ties in with the 800 wiring.

Now theoretically pin 5 of the DIN plug could be repurposed for the other audio channel, however on the 800 that is the chroma signal, which together with luma on pin 1 means I can (And do) use SVideo out on my 800.

So I can't repurpose either of those pins, so it looks like I am going to have to revert to my original plan of a trailing lead for stereo out on the 800 once the Acid Stereo upgrade is installed.

Not what I was hoping for but it will do the trick.

PhilC wrote: 12 Mar 2026 14:36

rubber_jonnie wrote: 12 Mar 2026 13:55

So I've been looking at the possibility of feeding stereo through the video jack of the 800 and it's not ideal.

The sound from the 800 is via pin 3 of the DIN connector. Checking several 5 pin din to phono (Composite+Audio) cables I have, the left/right audio channels are both connected together for mono sound and that ties in with the 800 wiring.

Now theoretically pin 5 of the DIN plug could be repurposed for the other audio channel, however on the 800 that is the chroma signal, which together with luma on pin 1 means I can (And do) use SVideo out on my 800.

So I can't repurpose either of those pins, so it looks like I am going to have to revert to my original plan of a trailing lead for stereo out on the 800 once the Acid Stereo upgrade is installed.

Not what I was hoping for but it will do the trick.

Ok that makes sense and once I remove the UHF cable I'll be able to run it through there.

exxos wrote: 13 Mar 2026 11:11 That's a pretty cool idea !

PhilC wrote: 13 Mar 2026 11:17 Thanks, I've got a load of the bigger ones that the 95144s and 96288s came in, I might see about using them for my pliers etc.