Stuff and Things.

[rubber_jonnie]

Well, the ribbon cable is just a big aerial.

Indeed.

I suspect it is interfering directly with the speaker TBH as it runs directly under it, though even trying with additional shielding made no difference, just the re-route to make it fine.

[HigashiJun]

I tried that and it didn't work...

And out of curiosity, what kind of insulation did you try ?

[rubber_jonnie]

I tried that and it didn't work...

And out of curiosity, what kind of insulation did you try ?

First I tried metalised cardboard folded over the cable with a clip onto ground, then aluminium tape similarly grounded.

The cable reroute does the trick so it's all good though I may revisit and put grounded aluminium tape under the speaker for a bit of extra shielding.

[HigashiJun]

...though I may revisit and put grounded aluminium tape under the speaker for a bit of extra shielding.

I guess that should do the trick.

[rubber_jonnie]

...though I may revisit and put grounded aluminium tape under the speaker for a bit of extra shielding.

I guess that should do the trick.

Every little helps

[rubber_jonnie]

So I added some aluminium tape to the keyboard PCB under the speaker and grounded it and whilst the flat cable for the ashtray ROM still has to be re-routed, the extra shielding does further improve the noise reduction.

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[rubber_jonnie]

Also finished tonight, the PC-Speed replica board that I built to test and be sure the boards I ordered work:

IMG20260415214550.jpg (298.07 KiB) Viewed 559 times

GALs are programmed so I just need to drop the CPU in and test in an ST

[rubber_jonnie]

Added a small hot plate to my toolbox as I have a very small PCB to populate soon for the Cosmac Elf II CDP1861 replacement and I think this will work best for that:

IMG_20260415_221723.jpg (182.27 KiB) Viewed 557 times

Whilst it's not ideal, it will get hot enough to melt my solder paste and should work for the TSSOP packages I'm working with. Just over a tenner so no big expenditure.

[HigashiJun]

Nice stuff.

Should do the job IMHO.

[rubber_jonnie]

Arrived yesterday, thanks to @alexh for flagging it up on eBay for me.

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Overall in good condition and works a treat

It does have a small cable relief issue where it's slightly pulled out, so I need to fix that and also lube the bearings, which are all open in the CX80.