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

new_psu.jpg

PSU in the machine

new_psu2.jpg

Test the machine boots with the new PSU

test_new_psu.jpg

Time to recap the video circuitry

video_old.jpg

All caps replaced and resistor added for sync

video_new.jpg

[Cosmic Puppet]

:bravo:

[exxos]

:bravo: Kill the rubbish marpet while your in there ;)

[rubber_jonnie]

@Steve Nice work sir.

[Steve]

Bye bye DRAM :)

IMG_20200814_121821.jpg

IMG_20200814_121802.jpg

[Cosmic Puppet]

That's awesome!

[Steve]

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

Holy mother of lord

IMG_20200814_131610.jpg

IMG_20200814_131646.jpg

Okay, job done lol

IMG_20200814_133035.jpg

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

IMG_20200814_154122.jpg

[PhilC]

Looks like a nice job there @Steve

[Steve]

Floppy drive resistor fix applied:

IMG_20200814_201402.jpg

Test floppy and system by loading frontier:

IMG_20200814_202613.jpg