Another Egyptian Enterprise 64

[rubber_jonnie]

Nice !

You have a crystal clear screen now.

There are still some graphical glitches here and there, but text is very sharp and I think the graphical glitches may well be related to programming tricks.

Either way they are not sufficient for me to be too worried about them.

[rubber_jonnie]

I'm going to have to get some more Pi Zeros then.

The Pi Zero v1.3 I ordered is due to be delivered today, Let me test how that performs as I expect it'll be less power hungry and if good enough as @alexh mentioned then it may be a cheaper way of doing it over the Pi Zero 2/2w.

I'll report back on it later.

[rubber_jonnie]

@PhilC

So the Pi Zero v1.3 arrived and power consumption is vastly improved over the 4B:

With the 4B and running the RGB2HDMI and FDD controller & Gotek with the game 'The Abyss':

PXL_20261027_120138037.jpg (246.75 KiB) Viewed 37 times

And with the Pi Zero v1.3 running the RGB2HDMI and FDD controller & Gotek with the game 'The Abyss':

PXL_20261027_132121936.jpg (226.6 KiB) Viewed 37 times

Thats considerably closer to how it was running without the RGB2HDMI and the FDD board before.

So a 300Ma saving. Not only that but the image quality on the program loader where it is colour cycling was a bit fizzy at times has also improved, so it seems the Pi Zero v1.3 is more than up to the job.

I've lost track of how many Pi's I've got through lately, but it's a fair few.

[PhilC]

@rubber_jonnie thanks, will be getting a couple of Pi Zeros I think and will likely do the Lynx and the Enterprise when I get some RGB2HDMI pcbs ordered.

[rubber_jonnie]

@rubber_jonnie thanks, will be getting a couple of Pi Zeros I think and will likely do the Lynx and the Enterprise when I get some RGB2HDMI pcbs ordered.

Definitely worth doing

[rubber_jonnie]

So doing some testing and this machine has blown our TR2 yet again...

It's a BC337 and is used in this circuit:

Screenshot 2026-10-30 at 10.52.32.png (341.05 KiB) Viewed 6 times

It looks to be part of a feedback system for the 12V circuit, though I'm not 100% on that, but my question is what is driving it so hard in that circuit that it blows?

TR3 perhaps? Could TR2 be staying on too long? Ultimate I'm assuming it is driving the voltage beyond the 9v mains input so that the 7812 can drive the 12 rail.

Any ideas would be most welcome!

[rubber_jonnie]

Where magic smoke comes from...

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