mrbomberzilly's MegaST maintenance

[Badwolf]

Now the blitter patch is fully installed within the CPU socket

That's some dead fancy soldering, Steve!

BW

[frank.lukas]

... you can also solder between the pins from the outside.

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[Badwolf]

... you can also solder between the pins from the outside.

Wow, you two are far too neat. I would have just relocated the board and run fly-wires to the bottom!

BW

[alexh]

Nice work. Enjoyable read.

Out of curiosity, as an alternative to a Blitter Patch board, are newer ICs available anywhere? Best Electronics? B&C?

(I understand that the distinguishing mark is the date code rather than a revision number)

[Steve]

And now for the finals, PSU recap using Panasonic FR caps & Nichicon for the 400v cap.

The PSU before re-cap

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The PSU after re-cap

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Testing the 12v rail

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Testing the 5v rail

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A happy MegaST4

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Thanks for all the kind comments! Will be shipping this back to @mrbombermillzy soon. Might just burn him a new TOS version before it leaves.

[exxos]

[alexh]

Nice work.

So this work stems from this thread? "Mandatory Fixes"?

https://exxosforum.co.uk/forum/viewtopic.php?t=1585

[stephen_usher]

I see that you have the same multimeter as I have... One of the good ones from Maplin in the 90s.

[Steve]

Nice work.

So this work stems from this thread? "Mandatory Fixes"?

https://exxosforum.co.uk/forum/viewtopic.php?t=1585

No not really. It's just a re-cap of everything. General tidy and service. Socket CPU for future upgrades etc. Bus resistors have been socketed so that @mrbombermillzy can change them without needing to solder, if he gets an accelerator later etc. Right now the system is functioning perfectly fine so the resistors are still original. But like I say, they can be swapped easily now if needed in the future.

This system is the test bed of his dual shifter board, so he just wanted it to be given some love and maintenance basically.

[mrbombermillzy]

This is some great work @Steve. I really appreciate the effort put in here.

I see that you have the same multimeter as I have... One of the good ones from Maplin in the 90s.

Funnily enough, although I have minimal electronics servicing/repair items, I still have this same multimeter as well! I remember picking it out in one of their old telephone book size catalogues, as it had a very good spec and was reasonably priced at the time. Wasn't there also a 'silver' version? I still have the original little operations manual (more like a leaflet) for it too.