Progress blog on CosmicPuppets STFM servicing

[Steve]

Hey guys,

Just a progress blog that I'll update as I go:

Motherboard: C070523-001

Problems:
* Corruption on DMA transfers, Ultrasatan
* Video output issues with sync/banding

Required services:
1. New Exxos PSU
2. STFM Video capacitor replacements (exxos kit)
3. Remove old motherboard ram
4. Complete motherboard re-cap
5. DMA and floppy resistor pull-up fixes

[Steve]

Just finished soldering in Exxos new PSU

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PSU in the machine

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Test the machine boots with the new PSU

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Time to recap the video circuitry

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All caps replaced and resistor added for sync

video_new.jpg (321.32 KiB) Viewed 5256 times

[Cosmic Puppet]

[exxos]

Kill the rubbish marpet while your in there

[rubber_jonnie]

@Steve Nice work sir.

[Steve]

Bye bye DRAM

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[Cosmic Puppet]

That's awesome!

[Steve]

Remove the cap inside the modulator he says... Steve says no problems...

Holy mother of lord

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Okay, job done lol

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Motherboard fully re-capped with Vishay, Panasonic and Nichicon caps.

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[PhilC]

Looks like a nice job there @Steve

[Steve]

Floppy drive resistor fix applied:

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Test floppy and system by loading frontier:

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